Patent Publication Number: US-2007106277-A1

Title: Remote controller for substance delivery system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      The present application is related to and claims the benefit of the earliest available effective filing date(s) from the following listed application(s) (the “Related Applications”) (e.g., claims earliest available priority dates for other than provisional patent applications or claims benefits under 35 USC §119(e) for provisional patent applications, for any and all parent, grandparent, great-grandparent, etc. applications of the Related Application(s)).  
     RELATED APPLICATIONS  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. ______, entitled REMOTELY CONTROLLED SUBSTANCE DELIVERY DEVICE, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Jan. 18, 2006, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. ______, entitled SUBSTANCE DELIVERY SYSTEM, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Jan. 18, 2006, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. ______, entitled REMOTE CONTROL OF SUBSTANCE DELIVERY SYSTEM, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Jan. 18, 2006, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/302,449, entitled OSMOTIC PUMP WITH REMOTELY CONTROLLED OSMOTIC PRESSURE GENERATION, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Dec. 13, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/302,321, entitled OSMOTIC PUMP WITH REMOTELY CONTROLLED OSMOTIC FLOW RATE, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Dec. 13, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/302,407, entitled REMOTE CONTROL OF OSMOTIC PUMP DEVICE, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Dec. 13, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/302,450, entitled METHOD AND SYSTEM FOR CONTROL OF OSMOTIC PUMP DEVICE, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Dec. 13, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/272,524, entitled REMOTE CONTROLLED IN SITU REACTION DEVICE, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Nov. 9, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/271,145, entitled REACTION DEVICE CONTROLLED BY MAGNETIC CONTROL SIGNAL, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Nov. 9, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/271,146, entitled REACTION DEVICE CONTROLLED BY RF CONTROL SIGNAL, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Nov. 9, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/270,799, entitled REMOTE CONTROLLED IN SITU REACTION METHOD, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Nov. 9, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/272,455, entitled REMOTE CONTROLLER FOR IN SITU REACTION DEVICE, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Nov. 9, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/272,572, entitled REMOTE CONTROLLED IN VIVO REACTION METHOD, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Nov. 9, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of U.S. patent application Ser. No. 11/272,573, IN SITU REACTION DEVICE, naming Leroy E. Hood, Muriel Y. Ishikawa, Edward K. Y. Jung, Robert Langer, Clarence T. Tegreene, Lowell L. Wood, Jr. and Victoria Y. H. Wood as inventors, filed Nov. 9, 2005, which is currently co-pending, or is an application of which a currently co-pending application is entitled to the benefit of the filing date.  
      The United States Patent Office (USPTO) has published a notice to the effect that the USPTO&#39;s computer programs require that patent applicants reference both a serial number and indicate whether an application is a continuation or continuation-in-part. Stephen G. Kunin,  Benefit of Prior - Filed Application,  USPTO Official Gazette Mar. 18, 2003, available at http://www.uspto.gov/web/offices/com/sol/og/2003/week11/patbene.htm. The present applicant entity has provided above a specific reference to the application(s)from which priority is being claimed as recited by statute. Applicant entity understands that the statute is unambiguous in its specific reference language and does not require either a serial number or any characterization, such as “continuation” or “continuation-in-part,” for claiming priority to U.S. patent applications. Notwithstanding the foregoing, applicant entity understands that the USPTO&#39;s computer programs have certain data entry requirements, and hence applicant entity is designating the present application as a continuation-in-part of its parent applications as set forth above, but expressly points out that such designations are not to be construed in any way as any type of commentary and/or admission as to whether or not the present application contains any new matter in addition to the matter of its parent application(s).  
      All subject matter of the Related Applications and of any and all parent, grandparent, great-grandparent, etc. applications of the Related Applications is incorporated herein by reference to the extent such subject matter is not inconsistent herewith. 
    
    
     BACKGROUND  
      Implantable controlled release devices for drug delivery have been developed. Certain devices rely upon the gradual release of a drug from a polymeric carrier over time, due to degradation of the carrier. Polymer-based drug release devices are being developed that include a drug in a ferropolymer that may be heated by an externally applied magnetic field, thus influencing the drug release. MEMS based drug release devices that include integrated electrical circuitry are also under development, as are MEMS based systems for performing chemical reactions. Implantable delivery devices have been developed for drug delivery purposes. Wireless transmission of electromagnetic signals of various frequencies is well known in the areas of communications and data transmission, as well as in selected biomedical applications.  
     SUMMARY  
      The present application relates, in general, to the field of fluid delivery devices, systems, and methods. In particular, the present application relates to remotely controlled delivery devices in which the concentration of a material in a fluid to be delivered may be varied. Control signals may be carried between a remote controller and a delivery device in an environment by electrical, magnetic, or electromagnetic fields or radiation. Embodiments of a system including a remotely controlled delivery device and associated controller are described. Methods of use and control of the device are also disclosed. According to various embodiments, a delivery device may be placed in an environment in order to eject or release a material into the environment. Exemplary environments include a body of an organism, a body of water or other fluid, or an enclosed volume of a fluid. According to some embodiments, a delivery device may provide for delivery of a fluid into a downstream fluid-handling structure. The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES  
       FIG. 1  depicts an embodiment of a delivery system for use in a human subject;  
       FIG. 2  depicts an embodiment of a delivery system including a remote controller;  
       FIG. 3  depicts another embodiment of a delivery system including a remote controller;  
       FIGS. 4A and 4B  illustrate in schematic form a change in concentration in a fluid to be delivered by an embodiment of a delivery device;  
       FIG. 5  depicts an electromagnetically responsive control element including a polymer and magnetically or electrically active components;  
       FIGS. 6A-6D  show examples of first active and second forms of primary material in delivery fluid;  
       FIGS. 7A and 7B  illustrate a change in concentration in delivery fluid in exemplary delivery device including an osmotic pump;  
       FIGS. 8A and 8B  illustrate a change in concentration in a delivery fluid produced by a heating element;  
       FIGS. 9A and 9B  illustrate a change in concentration in a delivery fluid produced by a cooling element;  
       FIGS. 10A and 10B  illustrate a change in concentration in a delivery fluid produced by interaction of a primary material with an interaction region;  
       FIGS. 11A and 11B  illustrate a change in concentration of primary material influenced by secondary material in a delivery fluid;  
       FIG. 12A  depicts an exemplary interaction region;  
       FIG. 12B  depicts expansion of the interaction region of  FIG. 12A  in a first direction;  
       FIG. 12C  depicts expansion of the interaction region of  FIG. 12A  in a second direction;  
       FIG. 12D  depicts expansion of the interaction region of  FIG. 12A  in first and second directions;  
       FIGS. 13A and 13B  depict unfolding of a pleated interaction region;  
       FIGS. 14A and 14B  depict another embodiment of an interaction region;  
       FIGS. 15A and 15B  depict an example of an effect of stretching an interaction region;  
       FIG. 16A and 16B  depict another example of an effect of stretching an interaction region;  
       FIG. 17A and 17B  depict an exemplary embodiment of an interaction region;  
       FIG. 18A and 18B  depict another exemplary embodiment of an interaction region;  
       FIG. 19A and 19B  depict another exemplary embodiment of an interaction region;  
       FIG. 20A and 20B  illustrate expansion of a delivery reservoir of a delivery device;  
       FIG. 21  is a schematic diagram of an embodiment of a delivery device;  
       FIG. 22  is a schematic diagram of another embodiment of a delivery device;  
       FIG. 23  depicts an embodiment of a system including a remotely controlled delivery device;  
       FIG. 24  depicts another embodiment of a system including a remotely controlled delivery device;  
       FIG. 25  depicts another embodiment of a system including a remotely controlled delivery device;  
       FIG. 26  illustrates a control signal generated from stored pattern data;  
       FIG. 27  illustrates a control signal calculated from a model based on stored parameters;  
       FIG. 28  is a schematic diagram of a remote controller;  
       FIG. 29  depicts an exemplary control signal;  
       FIG. 30  depicts another exemplary control signal;  
       FIG. 31  depicts another exemplary control signal;  
       FIG. 32  illustrates an embodiment of a delivery device including a downstream fluid handling structure;  
       FIG. 33  illustrates another embodiment of a delivery device including a downstream fluid handling structure;  
       FIG. 34  illustrates an embodiment of a delivery device including a fluid containing structure;  
       FIG. 35  illustrates an embodiment of a delivery device including an environmental interface;  
       FIG. 36  is a flow diagram of a method of delivering a fluid;  
       FIG. 37  is a flow diagram of a further method of delivering a fluid;  
       FIG. 38  is a flow diagram of a further method of delivery a fluid;  
       FIG. 39  is a schematic diagram of an embodiment of a system including a remote controller and a delivery device;  
       FIG. 40  is a diagram of an embodiment of a delivery system including a delivery device with an RFID;  
       FIG. 41  is a schematic diagram of an embodiment a system including a remote controller, a delivery device, and a sensor;  
       FIG. 42  is a schematic diagram of an embodiment a system including a remote controller and a delivery device including a sensor;  
       FIG. 43  is a schematic diagram of another embodiment of system including a remote controller and a delivery device; and  
       FIG. 44  is an embodiment of a system including a remote controller and a plurality of delivery devices in an environment.  
       FIG. 45  is a schematic of an embodiment of a delivery system;  
       FIG. 46  is a schematic of a further embodiment of a delivery system;  
       FIG. 47  is a schematic of a further embodiment of a delivery system;  
       FIG. 48  is a schematic of another embodiment of a delivery system;  
       FIG. 49  depicts an embodiment of a delivery system including encryption;  
       FIG. 50  depicts a embodiment of a delivery system that utilizes an authentication procedure;  
       FIG. 51  is a flow diagram of a method of delivering a fluid;  
       FIG. 52  is a flow diagram of a method of delivering a material;  
       FIG. 53  is a flow diagram of a portion of a method of delivering a material;  
       FIG. 54  is a flow diagram of another method of delivering a material;  
       FIG. 55  is a flow diagram of an expansion of the method of  FIG. 54 ;  
       FIG. 56  is a flow diagram of an expansion of the method of  FIG. 54 ;  
       FIG. 57  is a flow diagram of a further method of delivering a material;  
       FIG. 58  is a flow diagram of a method of controlling a delivery device;  
       FIG. 59  is an expansion of the method of  FIG. 58 ;  
       FIG. 60  is a flow diagram of additional steps for controlling a delivery device;  
       FIG. 61  is a flow diagram of alternative additional steps for controlling a delivery device;  
       FIG. 62  is a flow diagram of further alternative additional steps for controlling a delivery device;  
       FIG. 63  is a further expansion of the method of  FIG. 58 ;  
       FIG. 64  is another expansion of the method of  FIG. 58 ; and  
       FIG. 65  is still another expansion of the method of  FIG. 58 ;  
    
    
     DETAILED DESCRIPTION  
      In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrated embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here.  
       FIG. 1  depicts a first exemplary embodiment of a delivery system  10 . In the embodiment of  FIG. 1 , delivery system  10  includes delivery device  12  located in an environment  14 , (which in this particular example is a human body) and remote controller  16 . As used herein, the term “remote” refers to the transmission of information (e.g. data or control signals) or power signals or other interactions between spatially separated devices or apparatuses, such as the remote controller or the delivery system, without a connecting element such as a wire or cable linking the remote controller and the delivery system, and does not imply a particular spatial relationship between the remote controller and the delivery device, which may, in various embodiments, be separated by relatively large distances (e.g. miles or kilometers) or a relatively small distances (e.g. inches or millimeters). Delivery device  12  includes an electromagnetically responsive control element  18  that is responsive to an electromagnetic control signal generated by remote controller  16 .  
       FIG. 2  depicts an embodiment of a delivery system  20  including a delivery device  22  controlled by remote controller  24 . In the embodiment of  FIG. 2 , delivery device  22  includes pump  26  and delivery reservoir  28  which contains delivery fluid  30 . Remote controller  24  transmits electromagnetic control signal  32  to electromagnetically responsive control element  34  to control the concentration of primary material  36  in delivery fluid  30 . Pump  26  pumps delivery fluid  30  containing primary material  36  from delivery reservoir  28  via outlet  37 . Delivery device  22  also includes a body structure  38 .  
       FIG. 3  depicts another embodiment of a delivery system  40  including a delivery device  42  controlled by remote controller  44 . In the embodiment of  FIG. 3 , delivery device  42  includes pump  46  and delivery reservoir  28 , which contains delivery fluid  30 . Remote controller  44  transmits electromagnetic distribution control signal  32  to electromagnetically responsive control element  34  to control the concentration of primary material  36  in delivery fluid  30 . Remote controller  44  also transmits electromagnetic delivery control signal  48  to receiving element  50  in pump  46  to control the pumping of delivery fluid  30  from delivery reservoir  28 . Outlet  37  and body structure  38  are also included in delivery device  48 .  
      FIGS.  4 A and  4 BA illustrate in schematic form a delivery device  60  comprising a delivery reservoir  62  configured to contain a delivery fluid, the delivery reservoir having at least one outlet  64  through which the delivery fluid may exit the delivery reservoir; a delivery fluid  66  contained within the delivery reservoir  62 ; a primary material  68  contained within the delivery reservoir  62  and having a controllable effective concentration in the delivery fluid; and at least one electromagnetically responsive control element  70  adapted for modifying the distribution of the primary material between a first active form carried in the delivery fluid and a second form in response to an incident electromagnetic control signal, the effective concentration being the concentration of the first active form in the delivery fluid. Delivery fluid may exit delivery reservoir  66  by diffusion, or by being moved out of delivery reservoir  66  by positive pressure applied to delivery reservoir  62  (e.g. by a pump) or negative pressure generated downstream of delivery reservoir  62 .  FIG. 4A  illustrates a first state of electromagnetically responsive control element  70 , which causes primary material  68  to be in a first active form in delivery fluid  66 .  FIG. 4B  illustrates a second state of electromagnetic control element  70 , which causes the primary material to be in a second form  68 ′, which is not an active form carried in delivery fluid  66 , but may be, for example, insoluble in delivery fluid  66  as depicted in  FIG. 4B .  
      In order to modify the distribution of primary material between the first active form and the second form, the electromagnetically responsive control element used in this and other embodiments (e.g.,  34  in  FIGS. 2 and 3  or  70  in  FIGS. 4A and 4B ) may have various functional characteristics. In some embodiments, the electromagnetically responsive control element may include or form a heating element (e.g., a resistive element) or a cooling element (which may be, for example, a thermoelectric device). In some embodiments, the electromagnetically responsive control element may be an expanding element. In some embodiments, an electromagnetically responsive control element may include a receiving element such as an antenna or other geometric gain structure to enhance the receiving of an electromagnetic control signal transmitted from a remote control signal generator. The response of the electromagnetically responsive control element to an electromagnetic field may be due to absorption of energy from the electromagnetic signal or due to torque or traction on all or a portion of the electromagnetically responsive control element due to the electromagnetic field. The response will depend upon the intensity, the relative orientation and the frequency of the electromagnetic field and upon the geometry, composition and preparation of the material of the electromagnetically responsive control element. A response may occur on the macro level, on a microscopic level, or on a nanoscopic or molecular level. In some embodiments, the electromagnetically responsive control element may respond to the control signal by changing shape. In some embodiments, the electromagnetically responsive control element may respond to the control signal by changing in at least one dimension. The response of the electromagnetically responsive control element may include one or more of heating, cooling, vibrating, expanding, stretching, unfolding, contracting, deforming, softening, or folding globally or locally. In some embodiments, the electromagnetically responsive control element may be configured to selectively respond to an electromagnetic field having a specific frequency and orientation. Frequency selectivity may be conferred by appropriate selection of electromagnetically responsive control element size relative to the wavelength of the electromagnetic signal, while directional selectivity may be conferred by the configuration and orientation of the electromagnetically responsive control element.  
      Electromagnetically responsive control elements used in various embodiments of delivery devices and systems may include one or more electromagnetically active materials. The electromagnetically responsive control element may include a magnetically or electrically active material. Examples of magnetically active materials include permanently magnetizable materials, ferromagnetic materials such as iron, nickel, cobalt, and alloys thereof, ferrimagnetic materials such as magnetite, ferrous materials, ferric materials, diamagnetic materials such as quartz, paramagnetic materials such as silicate or sulfide, and antiferromagnetic materials such as canted antiferromagnetic materials which behave similarly to ferromagnetic materials; examples of electrically active materials include ferroelectrics, piezoelectrics, dielectric materials, including permanently ‘poled’ dielectrics and dielectrics having both positive and negative real permittivities, and metallic materials.  
      In some embodiments, the electromagnetically responsive control element may include a hydrogel, ferrogel, or ferroelectric. The electromagnetically responsive control element may include a polymer, ceramic, dielectric, or metal. The electromagnetically responsive control element may include various materials, such as polymers, ceramics, plastics, dielectrics or metals, or combinations thereof. In some embodiments, the electromagnetically responsive control element may include a polymer and a magnetically or electrically active component. In some embodiments, the electromagnetically responsive control element may include a shape memory material such as a shape memory polymer or a shape memory metal, or a composite structure such as a bimetallic structure.  
      In some embodiments, the electromagnetically responsive control element may include a polymer and an electrically active component (including highly polarizable dielectrics) or a magnetically active component (including ferropolymers and the like). In embodiments in which the electromagnetically responsive control element includes one or more electrically or magnetically active components, the electrically or magnetically active component may respond to an electromagnetic control signal in a first manner (e.g., by heating) and the response of the electromagnetically responsive control element may be produced in response to the electrically or magnetically active component (e.g. expansion or change in shape in response to heating of the electrically or magnetically active component). Electromagnetically responsive control elements may, in some embodiments, be composite structures.  
       FIG. 5  depicts an example of an electromagnetically responsive control element  100  including a composite structure formed from a polymer  102  and multiple electrically or magnetically active components in the form of multiple particles  104  distributed through polymer  102 . In some embodiments, the electrically or magnetically active components may be heatable by the electromagnetic control signal, and heating of the electrically or magnetically active components may cause the polymer to undergo a change in configuration. An example of a magnetically responsive polymer is described, for example, in Neto, et al, “Optical, Magnetic and Dielectric Properties of Non-Liquid Crystalline Elastomers Doped with Magnetic Colloids”; Brazilian Journal of Physics; bearing a date of March 2005; pp. 184-189; Volume 35, Number 1, which is incorporated herein by reference. Other exemplary materials and structures are described in Agarwal et al., “Magnetically-driven temperature-controlled microfluidic actuators”; pp. 1-5; located at: http://www.unl.im.dendai.ac.jp/INSS2004/INSS2004_papers/OralPresentations/C2.pdf or U.S. Pat. No. 6,607,553, both of which are incorporated herein by reference.  
      As mentioned in connection with  FIGS. 2-4B , the delivery device may contain a primary material (the material that is intended to be delivered to an environment or other downstream location) in a delivery fluid. The primary material may be distributed between a first active form (in which it is usable or active) and a second form in which it is inactive, inaccessible, or otherwise unavailable or unusable). The first active form of the primary material may be carried in solution, in suspension, in emulsion, or in colloidal suspension in the delivery fluid, so that it may be delivered from the delivery device along with the delivery fluid. In some embodiments, the second form may be an inactive form of the primary material, which may be carried in the delivery fluid along with the first active form. The second form may be carried in the delivery fluid in solution, in suspension, in emulsion, or in colloidal dispersion, for example.  
      In some such embodiments, the second form may be a chemically inactive form. This case is depicted in  FIG. 6A , in which the first active form is indicated by reference number  150 , and the second (chemically inactive) form is indicated by reference number  152 . Delivery reservoir  154 , including outlet  156  and electromagnetically responsive control element  158  are also indicated. Both first active form  150  and second form  152  are carried in delivery fluid  153 .  
      In other embodiments, as illustrated in  FIG. 6B , the second form  160  may include a chemically active form of the primary material  162  contained in a carrier structure  164 , while the first active form  166  is not contained in a carrier structure. The carrier structure may be, for example, a capsule, microcapsule, micelle, or fullerene, or other carrier structure known to those of skill in the relevant art. Delivery reservoir  154  includes outlet  156  and electromagnetically responsive control element  168 .  
      In still other embodiments, as illustrated in  FIG. 6C , the second form  176  may be bound or associated with an interaction region  178  in the delivery reservoir  154 , while the first active form  150  is carrier in delivery fluid  153 . Interaction of second form  176  with interaction region  178  may be controlled by electromagnetically responsive control element  180 .  
      As shown in  FIG. 6D , in some embodiments, the second form  186  may be insoluble in the delivery fluid  153 ; for example, the second form  186  may be precipitated out of the delivery fluid while first active form  188  is carried in delivery fluid  153 . As illustrated in  FIG. 6D , the delivery reservoir  154  may include filter  190  located between the delivery reservoir  154  and the outlet  156  and configured for removing the second form  186  from the delivery fluid  153 . For example, openings  192  in filter  190  may be large enough to allow first form  188  to pass through, but too small to allow precipitated second form  186  to pass through the filter. In other embodiments, the filter may operate based upon increased affinity for the second form over the first active form, or other filtering principle, as is well known in the field of filtration. The term ‘filter’ is intended to encompass various types of materials-separating device.  
      The primary material may have a different immunogenicity, reactivity, stability, or activity when it is in the first active form than when it is in the second form. The primary material may be any of a wide variety of materials, including single materials or mixtures of materials. For example, the primary material may be a pharmaceutical material or a neutraceutical material. The primary material may be a biologically active material. In some embodiments, the primary material may include at least one nutrient, hormone, growth factor, medication, therapeutic compound, enzyme, genetic material, vaccine, vitamin, neurotransmitter, cytokine, cell-signaling material, pro- or anti-apoptotic agent, imaging agent, labeling agent, diagnostic compound, nanomatrial, inhibitor, or blocker. In some embodiments, the primary material may be a component or precursor of a biologically active material; for example, the primary material may include at least one precursor or component of a nutrient, hormone, growth factor, medication, therapeutic compound, enzyme, genetic material, vaccine, vitamin, neurotransmitter, cytokine, cell-signaling material, pro- or anti-apoptotic agent, imaging agent, labeling agent, diagnostic compound, nanomaterial, inhibitor, or blocker. Such precursors, may include, for example, prodrugs (see, e.g., “Liver-Targeted Drug Delivery Using HepDirect1 Prodrugs,” Erion et al., Journal of Pharmacology and Experimental Therapeutics Fast Forward, JPET 312:554-560, 2005 (first pub Aug. 31, 2004) and “LEAPT: Lectin-directed enzyme-activated prodrug therapy”, Robinson et al., PNAS Oct. 5, 2004 vol. 101, No. 40, 14527-14532, published online before print Sep. 24, 2004 (http://www.pnas.org/cgi/content/full/101/40/14527), both of which are incorporated herein by reference. Beneficial materials may be produced, for example, by conversion of pro-drug to drug, enzymatic reaction of material in bloodstream (CYP450, cholesterol metabolism, e.g., with cholesterol monooxygenase, cholesterol reductase, cholesterol oxidase). Depending on the intended application or use environment for the delivery device, the primary material may include at least one fertilizer, nutrient, remediation agent, antibiotic, microbicide, herbicide, fungicide, transfection agent, nanomaterial, disinfectant, metal salt, a material for adjusting a chemical composition or pH, such as buffer, acid, base, chelating agent, emulsifying agent, or surfactant. In some embodiments, the primary material may include a tissue-specific marker or targeting molecule, which may be, for example, a tissue-specific endothelial protein. A tissue-specific marker or targeting molecule may assist in targeting of the primary material to a specific location or tissue within a body of an organism.  
      The term “delivery fluid” as used herein, is intended to cover materials having any form that exhibits fluid or fluid-like behavior, including liquids, gases, powders or other solid particles in a liquid or gas carrier. The delivery fluid may be a solution, suspension, or emulsion.  
      Typically, the effective concentration of the primary material will be the concentration of the first active form of the primary material in the delivery fluid, which may differ from the total concentration of primary material in the delivery fluid, which is the combined concentration of both the first active and second forms of the primary material. The effective rate of delivery of primary material from the delivery device will generally equal the rate at which delivery fluid is pumped (or otherwise moves or is moved) out of the delivery reservoir multiplied by the effective concentration of primary material in the delivery fluid. A delivery device may include a pump for pumping delivery fluid from the delivery reservoir. Alternatively, in some cases the primary material may simply diffuse out of the delivery device. Various types of pumps may be used, without limitation. Suitable pumps may include, for example, osmotich, mechanical, displacement, centrifugal, and peristaltic pumps.  
       FIGS. 7A and 7B  illustrate an embodiment of a delivery device that includes an osmotic pump. Delivery device  250  includes delivery reservoir  252 , which contains delivery fluid  254  and may have an outlet  256 . Electromagnetically responsive control element  258  is located in delivery reservoir  252  to control the distribution of primary material, which in  FIG. 7A  is shown in the second (inactive, inaccessible or unusable) form  260 . Osmotic pump  262  includes osmotic chamber  264  containing osmotic pressure generating material  266 . Semi-permeable membrane  268  is permeable to osmotic fluid  270  but not to osmotic pressure generating material  266 . Osmotic fluid  270  thus flows into osmotic chamber  264 . This causes movable barrier  274  (which may be a rigid movable barrier or a flexible membrane) to move into delivery reservoir  252 , thus pumping delivery fluid  254  out of outlet  256 . As shown in  FIG. 7B , activation of electromagnetically responsive control element  258  may cause primary material to be converted to first active form  272 .  
      Various different osmotic pressure-generating materials may be used in delivery systems as described herein. For example, the osmotic pressure-generating material may include ionic and non-ionic water-attracting or water absorbing materials, non-volatile water-soluble species, salts, sugars, polysaccharides, polymers, hydrogels, osmoopolymers, hydrophilic polymers, and absorbent polymers, among others. Water-attracting materials may include non-volatile, water-soluble species such as magnesium sulfate, magnesium chloride, potassium sulfate, sodium chloride, sodium sulfate, lithium sulfate, sodium phosphate, potassium phosphate, d-mannitol, sorbitol, inositol, urea, magnesium succinate, tartaric acid, raffinose, various monosaccharides, oligosaccharides and polysaccharides, such as sucrose, glucose, lactose, fructose, desxtran, and mixtures thereof. Water abosorbing materials include osmoopolymers, for example hydrophilic polymers that swell upon contact with water. Examples of water-absorbing materials include poly(hydroxyl alkyl methacrylates) MW 30,000-5,000,000, polyvinylpyrrolidone MW 10,000-360,000, anionic and cationic hydrogels, polyelectrolyte complexes, poly(vinyl alcohol) having low acetate residual, optionally cross linked with glyoxal, formaldehyde, or glutaraldehyde and having a degree of polymerization of 200 to 30,000, mixtures of e.g., methylcellulose, cross linked agar and carboxymethylcellulose; or hydroxypropyl methycellulose and sodium carboxymethylcellulose; polymers of N-vinyllactams, polyoxyethylene polyoxypropylene gels, polyoxybutylene-polyoxethylene block copolymer gels, carob gum, polyacrylic gels, polyester gels, polyuria gels, polyether gels, polyamide gels, polypeptide gels, polyamino acid gels, polycellulosic gels, carbopol acidic carboxy polymers MW 250,000-4,000,000, cyanamer polyacrylamides, cross-linked indene-maleic anhydride polymers, starch graft copolymers, acrylate polymer polysaccharides. Other water attracting and/or water absorbing materials include absorbent polymers such as poly(acrylic acid) potassium salt, poly(acrylic acid) sodium salt, poly(acrylic acid-co-acrylamide) potassium salt, poly(acrylic acid) sodium salt-graft-poly(ethylene oxid), poly(2-hydroxethyl methacrylate) and/or poly(2-hydropropyl methacrylate) and poly(isobutylene-co-maleic acid). A variety of osmotic pressure-generating materials and/or water-absorbing materials are described in US 2004/0106914 and US 2004/0015154, both of which are incorporated herein by reference in their entirety.  
      The osmotic pressure-generating ability of the osmotic pressure-generating material may depend on the solubility of the osmotic pressure-generating material in the osmotic fluid, and/or upon the concentration of the osmotic pressure-generating material in the osmotic fluid, and varying either concentration or solubility may modify the osmotic-pressure generating ability of the osmotic pressure-generating material. Concentration of the osmotic pressure-generating material in the osmotic fluid may be modifiable by a change in solubility of the osmotic pressure-generating material in response to an electromagnetic field control signal or by a change in the osmotic fluid in response to an electromagnetic field control signal.  
       FIGS. 8A and 8B  depict an embodiment of a delivery device  300  in which the electromagnetically responsive control element  302  includes an electromagnetic field responsive heating element that may respond to the control signal by producing heat. Primary material  304  is contained within delivery reservoir  306  in delivery fluid  307 . Electromagnetically responsive control element  302  may be located in the wall of delivery reservoir  306 . Electromagnetically responsive control element  302  has an initial temperature T 1 . Following heating of electromagnetically responsive control element  302  in response to an electromagnetic control signal, electromagnetically responsive control element  302  has a subsequent temperature T 2 , as shown in  FIG. 8B . The change in temperature of electromagnetically responsive control element  302  may modify the concentration of primary material  304  within delivery reservoir  306 . In  FIG. 8A , portion  305  of primary material  304  is insoluble, while in  FIG. 8B , all of primary material  304  has gone into solution, due to the change in temperature of delivery fluid  307 . The electromagnetic field responsive control element  302  may include a ferrous, ferric, or ferromagnetic material, or other material with a significant electromagnetic “loss tangent” or resistivity. In the present example, the solubility of the primary material  304  in the delivery fluid  307  is depicted as increasing with increasing temperature, but in some embodiments, the solubility may decrease with increasing temperature. As in previously described embodiment, delivery device  300  may also include pump  308  and outlet  310 .  
       FIGS. 9A and 9B  depict another embodiment of a delivery device  350 , in which the at least one electromagnetically responsive control element  352  may include an electromagnetic field responsive cooling element. The electromagnetic field responsive cooling element may be capable of producing a decrease in temperature in the delivery fluid, wherein the primary material  354  has a solubility in the delivery fluid  356  that changes in response to an decrease in temperature of the delivery fluid. The electromagnetic field responsive cooling element  352  may include a thermoelectric element, for example. Methods and/or mechanisms of producing cooling may include, but are not limited to, thermoelectric (Peltier Effect) and liquid-gas-vaporization (Joule-Thomson) devices, or devices which employ “phase-changing” materials or systems involving significant enthalpies of transition. The solubility of the primary material  354  may increase with decreasing temperature, or it may decrease with decreasing temperature, as depicted in  FIGS. 9A and 9B . In  FIG. 9A , for example, cooling element  352  is not producing cooling, and the temperature is at a higher temperature T 1  and primary material  354  is substantially all in solution in delivery fluid  356 . In  FIG. 9B , cooling element  352  may be activated to produce cooling, so that the temperature of delivery fluid  356  decreases to temperature T 2 . At temperature T 2  a portion  358  or primary material goes out of solution, resulting in a lower effective concentration of primary material in delivery fluid  356 .  
      In some embodiments of the delivery device, the at least one electromagnetically responsive control element may be a shape-changing structure that changes in at least one dimension in response to an electromagnetic control signal.  FIGS. 10A and 10B  depict delivery device  400  that includes an electromagnetically responsive control element  402  that is a shape-changing structure located in the wall of delivery reservoir  404 . An interaction region  406  including interaction sites  408  may be located on or adjacent to electromagnetically responsive control element  402 , so that the dimension of interaction region  406  is modified with the change in dimension of electromagnetically responsive control element  402 . Interaction sites  408  may bind primary material  410 , thus keeping it out of solution, and maintaining a lower effective concentration in delivery reservoir  404 ; a change in spacing or exposure of interaction sites  408  may modify the interaction of primary material  410  with interaction sites  408 , and thus modifies the effective concentration in delivery reservoir  404 . For example, in  FIG. 10B , the electromagnetically responsive control element  402 ′ has contracted in at least one dimension to produce a corresponding decrease in size of interaction region  406 , and reduction in spacing between interaction sites  408 . In the example depicted in  FIG. 10B , the reduction in interaction site spacing reduces interactions with primary material  410 , causing it to go into solution in delivery fluid  412  in higher concentration.  
      Interaction sites may be localized to an interaction region, as depicted in  FIGS. 10A and 10B , or, in alternative embodiments, the interaction sites may be distributed to various locations within the delivery reservoir. The delivery device may include a plurality of interaction sites for the primary material within the delivery reservoir, the likelihood of interaction of the primary material with the interaction sites controllable by the electromagnetic field control signal, wherein interaction of the primary material with the interaction sites causes a change in effective concentration within the delivery reservoir. The interaction sites may be capable of interacting with the primary material by one or more of binding, reacting, interacting, or forming a complex with the primary material. The interaction sites may be responsive to an electromagnetic field control signal by a change in at least one characteristic, the change in the at least one characteristic modifying the interaction between the interaction sites and the primary material. The at least one characteristic may include, but is not limited to, at least one of a solubility, a reactivity, a distribution within the delivery reservoir, a density, a temperature, a conformation, an orientation, an alignment, or chemical potential, for example.  
      In some embodiments, the at least one electromagnetically responsive control element may be an electromagnetic field responsive molecule in the delivery fluid, and wherein the electromagnetic field responsive molecule undergoes a change in conformation from a first conformation state to a second conformation state in response to the electromagnetic control signal, and wherein the first conformation state has a first solubility in the delivery fluid and wherein the second conformation state has a second solubility in the delivery fluid. Such an electromagnetic field responsive molecule may form at least a portion of the primary material in the delivery fluid, or alternatively, the electromagnetic field responsive molecule may form at least a portion of a secondary material that influences the solubility of the primary material in the delivery fluid, as illustrated in  FIGS. 11A and 11B .  
       FIG. 11A  depicts a delivery device  420  including delivery reservoir  422  and pump  424 . Delivery reservoir  422  contains delivery fluid  425 , primary material  426 , and secondary material  428 . Delivery fluid  424  may exit delivery reservoir  422  via outlet  430 . In  FIG. 11A , secondary material  428  is all in solution, and a portion  432  of primary material has been forced out of solution. In  FIG. 11B , in response to a change in the electromagnetic field control signal, a portion  434  of secondary material  428  has gone out of solution, with the effect that a larger amount of primary material  426  goes into solution, thus increasing the concentration of primary material  426  in delivery fluid  242 . Secondary material  428  may influence the concentration of primary material  426  by modifying the pH, polarity or other characteristic of delivery fluid  244 , or by interacting or reacting with primary material  426  directly to modify its solubility in delivery fluid  424 .  
       FIGS. 10A and 10B  depict one method of using a shape changing material to vary the effective concentration of a primary material in a delivery device. Other embodiments that utilize shape-changing materials are also contemplated. A shape-changing structure may include a polymeric material, a ferropolymer, a hydrogel, a bimetallic structure, or a shape memory material. In some embodiments, the shape-changing structure may be an expanding or contracting structure, wherein the change in at least one dimension includes an expansion or contraction in at least one dimension. Expansion or contraction of the expanding or contracting structure may modify the volume of a delivery reservoir, or expose molecular structures to the delivery fluid that modify the solubility of the primary material in the delivery fluid, as will be discussed in the following example.  
      A change in surface area may be produced by stretching a portion of the delivery reservoir, as depicted in  FIGS. 12A-12D , or a change in surface area may be produced by unfolding a portion of the delivery reservoir, as depicted in  FIGS. 13A and 13B , or by some of change in conformation of at least a portion of the delivery reservoir.  
       FIGS. 12A-12D  depict the effect of changes in one or two dimensions on an interaction region  450 . Such an interaction region may be formed, for example, on an electromagnetically responsive control element that expands in response to a control signal. Interaction region  450  may include a plurality of reaction sites  452 , and having initial length of x 1  in a first dimension and y 1  in a second dimension.  FIG. 12B  depicts interaction region  450  following a change in the first dimension, to a length x 2 .  FIG. 12C  depicts interaction region  450  following a change in the second dimension, to a length y 2 , and  FIG. 12D  depicts interaction region  450  following a change in both the first and second dimensions, to a size of x 2  by y 2 . In each case, a change in dimension results in a change in distance between reaction sites  452 . The dimension change depicted in  FIGS. 12A-12D  may be viewed as a ‘stretching’ or ‘expansion’ of the interaction region. Increasing the surface area of the interaction region may increase the rate of the reaction. Increasing the surface area of the interaction region (e.g., by stretching the surface) may increase the distance between reaction sites on the interaction region. An increased distance between reaction sites may lead to an increase in reaction rate (for example, in cases where smaller spacing between reaction sites leads to steric hindrance that blocks access of reactants to reaction sites).  
      In addition to increasing surface areas or reaction volumes, expansion of an electromagnetically responsive control element may also have the effect of exposing additional portions of an interaction region or exposing additional functional group to influence a reaction condition. Increasing the surface area of the interaction region by unfolding or other forms of ‘opening’ of the interaction region structure of at least a portion of the reaction area may increase the number of reaction sites on the interaction region (e.g. by exposing additional reaction sites that were fully or partially hidden or obstructed when the interaction region was in a folded configuration). For example, the area of an interaction region may be increased by the unfolding of at least a portion of the reaction area to expose additional portions of the reaction area, as depicted in  FIGS. 13A and 13B . In  FIG. 13A , an interaction region  500 , which includes or is made up of an electromagnetically responsive control element, can be expanded by unfolding to the form depicted in  FIG. 13B . Interaction region  500  has a pleated structure that includes ridges  502   a - 502   e  and valleys  504   a - 504   d.  Reaction sites  506  may be located in or on ridges  502   a - 502   e  and valleys  504   a - 504   d.  In the folded form illustrated in  FIG. 13A , reaction sites  506  located in valleys  504   a - 504   d  are ‘hidden’ in the sense that reactants may not fit into the narrow valleys to approach those reaction sites, while reaction sites on ridges  502   a - 502   e  remain exposed. When interaction region  500  is unfolded to the form shown in  FIG. 13B , reaction sites  506  in valleys  504   a - 506   d  are exposed, because the open valleys permit access of reactants to the reaction sites in the valleys. Examples of materials that unfold in response to electromagnetic fields include ionic polymer-metal composites (IPMC) as described in Shahinpoor et al., “Artificial Muscle Research Institute: Paper: Ionic Polymer-Metal Composites (IPMC) As Biomimetic Sensors, Actuators and Artificial Muscles-A Review”; University of New Mexico; printed on Oct. 21, 2005; pp. 1-28; located at: http://www.unm.edu/˜amri/paper.html, which is incorporated herein by reference.  
      Increasing the surface area of the interaction region may decrease the rate of the interaction in some circumstances and increase the rate of interaction in others. Exposure of additional portions of the interaction region may expose additional functional groups that are not reaction sites, but that may produce some local modification to a surface property of the interaction region that in turn modifies the rate or kinetics of the reaction. For example, exposed functional groups may produce at least a local change in pH, surface energy, or surface charge. See, for example, U.S. patent publication 2003/0142901 A1, which is incorporated herein by reference. A related modification of the interaction region may include an increase in porosity or decrease in density of an electromagnetically responsive control element. An increase in porosity may have a similar effect to unfolding with respect to modifying the spacing or exposure of reaction sites, functional groups, etc. See, for example U.S. Pat. Nos. 5,643,246, 5,830,207, and 6,755,621, all of which are incorporated herein by reference.  FIGS. 14A and 14B  depict an electromagnetically responsive control element  530  that expands in response to an electromagnetic control signal, with a corresponding increase in size of pores  532  in  FIG. 14B  relative to the size of pores  532  in  FIG. 14A .  
      A change in the spacing of interaction sites may increase or decrease the rate of interaction, or modify another parameter of an interaction, in a manner that depends on the specific reaction and reactants. Heating or cooling of a reaction volume may also modify a chemical reaction by modifying the pressure or the pH or the osmolality or other reaction-pertinent chemical variables within the reaction space. In some embodiments, a delivery device may include at least one interaction region capable of interacting with the primary material by one or more of binding, reacting, interacting, or forming a complex with the primary material. The at least one interaction region may be responsive to the electromagnetic control signal by a change in at least one characteristic, the change in the at least one characteristic modifying the interaction between the at least one interaction region and the primary material. For example, the at least one characteristic may include at least one solubility, reactivity, temperature, conformation, orientation, alignment, binding affinity, chemical potential, surface energy, porosity, osmolality, pH, distribution within the delivery reservoir, or density. In some embodiments, at least a portion of the delivery reservoir containing the at least one interaction region may be responsive to an electromagnetic control signal by a change in the surface area of the portion of the delivery reservoir, the change in surface area modifying the likelihood of interaction of the primary material with the at least one interaction region. For example, the change of surface area may be produced by stretching or expansion of the portion of the delivery reservoir, or by unfolding of the portion of the delivery reservoir.  
      The influence of modifying the surface area of an interaction region is described further in connection with  FIGS. 15A and 15B  and  16 A and  16 B.  FIGS. 15A and 15B  illustrate how an increase of the surface area of an interaction region by stretching or expansion may increase the rate of the interaction occurring at the interaction region. Multiple interaction sites  552  are located in interaction region  550 . As shown in  FIG. 15A , prior to stretch or expansion, interaction sites  552  are close together, and primary material  554 , which binds to the interaction sites  552 , is sufficiently large that it is not possible for reactant  554  to bind to each interaction site  552 . When interaction region  550  has been stretched or expanded to expanded form  550 ′ as depicted in  FIG. 15B , so that the interaction sites  552  are further apart, it is possible for primary material  554  to bind to a larger percentage of the interaction sites, thus increasing the rate of interaction.  
      In some embodiments, an increase in the surface area of the interaction region by stretching or expansion may decrease the interaction rate (for example, in cases where a particular spacing is needed to permit binding or association of primary material with several interaction sites simultaneously).  FIGS. 16A and 16B  illustrate how an increase in the surface area of an interaction region  570  by stretching or expansion may decrease the rate of the interaction occurring at the interaction region. Again, multiple interaction sites  572  and  574  are located in the interaction region  570 , as depicted in  FIG. 16A . In the present example binding of a primary material  576  to interaction region  570  requires binding of a primary material  576  to two interaction sites  572  and  574 . When interaction region  570  is stretched or expanded to expanded form  570 ′ as depicted in  FIG. 16B , the spacing of the two interaction sites  572  and  574  is changed so that primary material  576  does not readily bind to interaction region in the expanded form  570 ′, thus reducing the rate of interaction.  
      Many materials expand when thermal energy is applied. By combining materials as in polymer gels one can use the differing properties of individual components to affect the whole. Thermally-responsive materials include thermally responsive gels (hydrogels) such as thermosensitive N-alkyl acrylamide polymers, Poly(N-isopropylacrylamide) (PNIPAAm), biopolymers, crosslinked elastin-based networks, materials that undergo thermally triggered hydrogelation, memory foam, resin composites, thermochromic materials, proteins, memory shape alloys, plastics, and thermoplastics. Materials that contract or fold in response to heating may include thermally-responsive gels (hydrogels) that undergo thermally triggered hydrogelation (e.g. Polaxamers, uncross-linked PNIPAAm derivatives, chitosan/glycerol formulations, elastin-based polymers), thermosetting resins (e.g. phenolic, melamine, urea and polyester resins), dental composites (e.g. monomethylacrylates), and thermoplastics.  
      Some examples of reactions that may be sped up by change in distance between reaction sites include those involving drugs designed with spacers, such as dual function molecules, biomolecules linked to transition metal complexes as described in Paschke et al, “Biomolecules linked to transition metal complexes—new chances for chemotherapy”; Current Medicinal Chemistry; bearing dates of October 2003 and Oct. 18, 2005, printed on Oct. 24, 2005; pp. 2033-44 (pp. 1-2); Volume 10, Number 19; PubMed; located at: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cm d=Retrieve&amp;db=PubMed&amp;list_uids=1 2871101&amp;dopt=Abstract, and Schiff bases as described in Puccetti et al., “Carbonic anhydrase inhibitors”, Bioorg. Med. Chem. Lett. Jun. 15, 2005; 15(12): 3096-101 (Abstract only), both of which are incorporated herein by reference. Other reactions include reactions responding to conformational (allosteric) changes including regulation by allosteric modulators, and reactions involving substrate or ligand cooperativity in multiple-site proteins, where binding affects the affinity of subsequent binding, e.g., binding of a first O 2  molecule to Heme increases the binding affinity of the next such molecule, or influence of Tau on Taxol, as described in Ross et al., “Tau induces cooperative Taxol binding to microtubules”; PNAS; Bearing dates of Aug. 31, 2004 and 2004; pp. 12910-12915; Volume 101, Number 35; The National Academy of Sciences of the USA; located at: http://gabriel.physics.ucsb.edu/˜deborah/pub/RossPNASv101p12910y04.pdf, which is incorporated herein by reference. Reactions or interactions that may be slowed down by increased reaction site spacing include reactions responsive to conformational (allosteric) changes, influence or pH, or crosslinking. See for example Boniface et al., “Evidence for a Conformational Change in a Class II Major Histocompatibility Complex Molecule Occuring in the Same pH Range Where Antigen Binding Is Enhanced”; J. Exp. Med.; Bearing dates of January 1996 and Jun. 26, 2005; pp. 119-126; Volume 183; The Rockefeller University Press; located at: http://www.jem.org also incorporated herein by reference or Sridhar et al., “New bivalent PKC ligands linked by a carbon spacer: enhancement in binding affinity”; J Med Chem.; Bearing dates of Sep. 11, 2003 and Oct. 18, 2005, printed on Oct. 24, 2005; pp. 4196-204 (pp. 1-2); Volume 46, Number 19; PubMed (Abstract); Located at: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&amp;db=PubMed&amp;list_uids=1 2954072&amp;dopt=Abstract, also incorporated herein by reference.  
      In some embodiments, the interaction region may include interaction sites that include a secondary material capable of interacting with or influencing the solubility of the primary material. The electromagnetically responsive control element may modify the influence of the secondary material. In some embodiments the secondary material may not be localized to an interaction region, but may be distributed within the delivery reservoir, but responsive to an electromagnetic control signal. The secondary material may interact with or influence primary material in a variety of ways. As a first example, the secondary material may be a receptor or other binding location that binds or sequesters the primary material, either specifically or non-specifically, to take it out of solution.  FIGS. 17A and 17B  depict an interaction between primary material  600  and secondary material  602  in interaction region  604 . In  FIG. 17A , prior to activation of electromagnetically responsive control element  606 , primary material  600  does not bind to secondary material  602  in interaction region  604 . Following activation of electromagnetically responsive control element  606 , secondary material  602  undergoes a change to modified form  602 ′ as depicted in  FIG. 17B , which allows primary material  600  to bind to it and go out of solution, thus reducing the effective concentration of the primary material in the delivery fluid.  
      In the example shown in  FIG. 18A and 18B , secondary material  630  is not itself a receptor or binding site for the primary material  632 , but modifies interaction between the primary material  632  and an interaction site  634  (which may be, for example, a binding or receptor site) in interaction region  636 . In  FIG. 18A , the secondary material  630  is in a first configuration which blocks access of primary material  632  to interaction site  634 . In  FIG. 18B , under the influence of electromagnetically responsive control element  638 , secondary material  630  has assumed a second configuration  630 ′ which permits access of primary material  632  to interaction site  634 . Secondary material  630  may be a material that modifes the rate or nature of the interaction between primary material  632  and interaction site  634  in response to an electromagnetic control signal by steric effects, by modifying the polarity of at least a portion of an interaction region, such as e.g., hydrophobic or hydrophilic groups; by modifying the pH of at least a portion of the interaction region, with acids or acidifiers (e.g., ammonium chloride), bases or alkalizers (sodium bicarbonate, sodium acetate) or buffering agents (e.g., mono- or di-hydrogen phosphates); or it may be a material that modifies the charge of at least a portion of the interaction region, such as including various enzyme, neuraminidase, transferase, antioxidants, and charge donors.  
      In the example of  FIGS. 19A and 19B , secondary material  640  is a reactant that reacts with primary material  642  to produce reaction product  644 . Primary material  642  approaches secondary material  640  in interaction region  646  in  FIG. 19A , and reaction product  644  leaves interaction region  646  in  FIG. 19B . The reaction between secondary material  640  and primary material  642  is caused, produced, facilitated, or otherwise increased or enhanced by activation of electromagnetically responsive control element  648 , (e.g., to produce heating, cooling, a change in surface charge, conformation, etc.) Reaction product  646  may have a different effective concentration in the delivery fluid than primary material  642  due to different solubility, or chemical activity, for example, or because the reaction results in an increase or decrease in the number of chemically active molecules in the reaction chamber. A reaction by-product  610  may remain at interaction region  646 , as depicted in  FIG. 19B , or secondary material  640  may be completely consumed by the reaction.  
      The influence of the electromagnetically responsive control element in the examples depicted in  FIGS. 17A-19B  may be any of various influences, including but not limited to those described herein; e.g., modifying the temperature of the interaction region or exposing reaction sites or functional groups. The interaction that takes place at the interaction region may change the effective concentration of primary material within the delivery reservoir by producing reaction products in different quantities or with different solubility or chemical activity than the reactants. In some embodiments, the interaction region may include a catalyst that facilitates a chemical reaction but is not modified by the chemical reaction, for example, metals such as platinum, acid-base catalysts, catalytic nucleic acids such as ribozymes or DNAzymes. The interaction region may include an enzyme, such as an oxidoreductase (e.g. glucose oxidase), transferase (including glycosyltransferase, kinase/phosphorylase), hydrolase, lyase, isomerase, ligase, and enzymatic complexes and/or cofactors. Various examples of catalysts are provided in Kozhevnikov, “Catalysts for Fine Chemical Synthesis, Volume 2, Catalysis by Polyoxometalates”; Chipsbooks.com; Bearing dates of 2002 and 1998-2006, printed on Oct. 21, 2005; pp 1-3 (201 pages); Volume 2; Culinary and Hospitality Industry Publications Services; located at: http://www.chipsbooks.com/catcem2.htm, which is incorporated herein by reference.  
      Modifying a reaction condition at the interaction region may also be accomplished by heating or cooling at least a portion of the interaction region, or by modifying the osmolality or pH, surface charge, or surface energy of at least a portion of the interaction region. Similarly, modifying a reaction condition at the interaction region may include modifying a parameter of a reaction space within the delivery device, the reaction space containing the interaction region, e.g. by modifying the volume of the reaction space, heating or cooling at least a portion of the reaction space, or modifying the osmolality, pH, pressure, temperature, chemical composition, or chemical activity of at least a portion of the reaction space.  
      In some embodiments, expansion or other conformation change of an electromagnetically responsive control element may produce other modifications to a condition in the delivery reservoir. For example, a volume of a delivery reservoir containing the interaction region may be increased by expansion of an electromagnetically responsive control element, as depicted in  FIGS. 20A and 20B . Delivery device  650  includes delivery reservoir  652  containing primary material  654  and delivery fluid  656  and having a first volume as shown in  FIG. 20A . An electromagnetically responsive control element  658  that changes dimension in response to an electromagnetic control signal forms an expandable portion of the wall of delivery reservoir  652 . Upon expansion of electromagnetically responsive control element to expanded form  658 ′ shown in  FIG. 20B , the volume of delivery reservoir  652  is increased, and the concentration of primary material  654  within delivery reservoir  652  is thus decreased. In this and other embodiments, the delivery device may include at least one sensor  660  for detecting at least one parameter from the delivery reservoir. For example, the sensor may detect a quantity or concentration of primary material in the delivery reservoir. In other embodiments, the delivery device may include at least one sensor for detecting a concentration or activity of a chemical within at least a portion of an environment surrounding the delivery device. Examples of sensors are described in, U.S. Pat. No. 6,935,165, and U.S. Patent Publication 2004/0007051, both of which are incorporated herein by reference.  
       FIG. 21  depicts in schematic form an embodiment of a delivery device  700  including an electromagnetically responsive control element  702  that includes an active portion  704  and a power receiving structure  706 . Delivery device also includes delivery reservoir  708  and outlet  710 . Power receiving structure  706  may be any structure that has a size, shape, and material that is suitable for receiving and transducing electromagnetic energy of a particular frequency or frequency band. The power receiving structure may include an antenna. The power receiving structure may include a resonant structure. The resonant structure may be a resonant circuit, a molecular bond, or a mechanically resonant structure. In some embodiments, power receiving structure  706  may be highly frequency-selective, while in other embodiments it may react usefully over a wide frequency band, or over multiple frequency bands. Power receiving structure  706  may be formed of various metallic or electrically or magnetically active materials. Active portion  704  may include various materials that respond mechanically, thermally or chemically to electromagnetic energy received and transduced by power receiving structure  706  to influence the effective concentration of primary material in delivery reservoir.  
       FIG. 22  depicts an embodiment of a delivery device  750  including an RFID  752 . Delivery device  750  includes delivery reservoir  754 , outlet  756  and electromagnetically responsive control element  758 . RFID  752  may store a unique identification code that allows delivery device  750  to be identified by a remote controller (not shown) that includes RFID detection circuitry. This provides for selective control of particular delivery devices, for example.  
      Delivery devices as described herein may be configured for use in a variety of environments. A delivery device of the type disclosed herein may include a body structure (e.g., body structure  38  in  FIGS. 2 and 3 ) adapted for positioning in an environment selected from a body of an organism, as depicted in  FIG. 1 , or a body of water, or a contained fluid volume. The delivery reservoir may be located within the body structure. The body structure adapted for positioning in a contained fluid volume selected from an industrial fluid volume, an agricultural fluid volume, a swimming pool, an aquarium, a drinking water supply, a potable water supply, and an HVAC system cooling water supply.  
      Various embodiments may be used in connection with selected biomedical applications (e.g., with delivery devices adapted for placement in the body of a human or other animal). It is also contemplated that delivery systems as described herein may be used in a variety of environments, not limited to the bodies of humans or other animals. Delivery devices may be placed in other types of living organisms (e.g., plants). The environments for use of embodiments described herein are merely exemplary, and the delivery systems as disclosed herein are not limited to use in the applications presented in the examples.  
       FIG. 23  illustrates an exemplary embodiment of a delivery system  770  in which a delivery device  772  is located in a small enclosed fluid volume  774  (e.g., an aquarium). A remote controller  776  is located outside enclosed fluid volume  774 .  
       FIG. 24  illustrates a further exemplary embodiment of a delivery system  780  in which a delivery device  782  is located in a larger enclosed fluid volume  784  (which may be, for example, a water storage tank, an HVAC system cooling water tank, a tank containing an industrial fluid or an agricultural fluid). A remote controller  786  is located outside enclosed fluid volume  784 .  
       FIG. 25  illustrates a further exemplary embodiment of a delivery system  790  in which a delivery device  792  is located in a body of water  794  (a lake or pond is depicted here, but such delivery systems may also be designed for use in rivers, streams, or oceans). A remote controller  796  is shown located outside of body of water  794 , though in some embodiments it may be advantageous to place remote controller  796  at a location within body of water  794 .  
      The body structure of the delivery device may be adapted for a specific environment. The size, shape, and materials of the body structure influence suitability for a particular environment. For example, a device intended for use in a body of a human or other organism would typically have suitable biocompatibility characteristics. For use in any environment, the body structure (and device as a whole) may be designed to withstand environmental conditions such as temperature, chemical exposure, and mechanical stresses. Moreover, the body structure may include features that allow it to be placed or positioned in a desired location in the environment, or targeted to a desired location in the environment. Such features may include size and shape features, tethers or gripping structures to prevent movement of the body structure in the environment (in the case that the device is placed in the desired location) or targeting features (surface chemistry, shape, etc.) that may direct the device toward or cause it to be localized in a desired location. The body structure may include a tissue-specific marker or targeting molecule. For example, the tissue specific marker or targeting molecule may be a tissue specific endothelial protein. Small devices (e.g. as may be used for placement in the body of an organism) may be constructed using methods known to those in skill of the art of microfabrication. In applications where size is not a constraint, a wide variety of fabrication methods may be employed. The body structure of the delivery device may be formed from various materials or combinations of materials, including but not limited to plastics and other polymers, ceramics, metals, and glasses, and by a variety of manufacturing techniques.  
      In some embodiments, the delivery device may be a MEMS device or other microfabricated device. The delivery device may be constructed from at least one polymer, ceramic, glass, or semiconductor material. In some embodiments, the delivery device may be a battery-free device, powered by power beaming, inductive coupling, or an environmental power source. In still other embodiments, the device may include a battery or other on-board power source. In some embodiments, the delivery device may include an electromagnetic control signal generator, which may be located substantially in, on or adjacent to the delivery reservoir. In other embodiments, the electromagnetic control signal generator may be located at a location remote from the delivery reservoir.  
      As discussed herein, a remote controller for a delivery device may include an electromagnetic signal generator capable of producing an electromagnetic signal sufficient to activate an electromagnetically responsive control element of a delivery device located in an environment to change a concentration of a primary material within a delivery reservoir of the delivery device; and an electromagnetic signal transmitter capable of wirelessly transmitting the electromagnetic signal to the electromagnetically responsive control element. Various types and frequencies of electromagnetic control signals may be used in delivery systems as described herein. For example, in some embodiments, the delivery system may include a remote controller configured to generate a static or quasi-static electrical field control signal or static or quasi-static magnetic field control sufficient to activate the electromagnetically responsive control element to control the effective concentration of primary material in a desired manner. In other embodiments, the remote controller may be configured to generate a radio-frequency, microwave, infrared, millimeter wave, optical, or ultraviolet electromagnetic field control signal sufficient to activate the electromagnetically responsive control element to control the effective concentration of primary material in a desired manner.  
      The electromagnetic control signal may be produced based at least in part upon a predetermined activation pattern. As shown in  FIG. 26 , a predetermined activation pattern may include a set of stored data  1002   a,    1002   b,    1002   c,    1002   d,  . . .  1002   e,  having values f(t 1 ), f(t 2 ), f(t 3 ), f(t 4 ), . . . f(t N ), stored in a memory location  1000 . The activation pattern upon which the electromagnetic signal is based is depicted in plot  1004  in  FIG. 26 . In plot  1004 , time t n  is indicated on axis  1006  and signal amplitude f(t n ), which is a function of t n , is indicated on axis  1008 . The value of the electromagnetic signal over time is represented by trace  1010 . The predetermined activation pattern represented by data  1002   a,    1002   b,    1002   c,    1002   d,  . . .  1002   e  may be based upon calculation, measurements, or any other method that may be used for producing an activation pattern suitable for activating an electromagnetically responsive control element. Memory  1000  may be a memory location in a remote controller. As an example, a simple remote controller may include a stored activation pattern in memory and include electrical circuitry configured to generate an electromagnetic control signal according to the pattern for a preset duration or at preset intervals, without further input of either feedback information or user data. In a more complex embodiment, a predetermined activation pattern may be generated in response to certain feedback or user input conditions.  
      In some embodiments, an electromagnetic signal may be produced based upon a model-based calculation. As shown in  FIG. 27 , an activation pattern f(t n ) may be a function not only of time (t n ) but also of model parameters P 1 , P 2 , . . . P k , as indicated by equation  1050 . Data  1052   a,    1052   b,  . . .  1052   c  having values P 1 , P 2 , . . . P k  may be stored in memory  1054 . An electromagnetic control signal may be computed from the stored model parameters and time information. For example, as indicated in plot  1056 , time is indicated on axis  1058  and the strength or amplitude of the electromagnetic control signal is indicated on axis  1060 , so that trace  1061  represents f(t n ). Memory  1054  may be a memory location in a remote controller. The remote controller may generate an electromagnetic control signal based upon the stored function and corresponding parameters. In some embodiments, the electromagnetic control signal may also be a function of one or more feedback signals (from the delivery device or the environment, for example) or of some user input of data or instructions.  
       FIG. 28  depicts a remote controller  1100  having a memory  1104  capable of storing pre-determined data values or parameters used in model-based calculation, as described in connection with  FIGS. 29 and 30 . Remote controller  1100  may also include electrical circuitry  1102 , signal generator  1112 , and signal transmitter  1114  for transmitting electromagnetic control signal  1116 . Memory  1104  may include memory location  1106  for containing a stored activation pattern or model parameters; portions of memory  1104  may also be used for storing operating system, program code, etc. for use by processor  1102 . The controller  1100  may also include a beam director  1118 , such as an antenna, optical element, mirror, transducer, or other structure that may impact control of electromagnetic signaling. The electrical circuitry may include any or all of analog circuitry, digital circuitry, one or more microprocessors, computing devices, memory devices, and so forth. Remote controller may include at least one of hardware, firmware, or software configured to control generation of the electromagnetic control field signal. Software may include, for example, instructions for controlling the generation of the electromagnetic control signal and instructions for controlling the transmission of the electromagnetic control signal to the electromagnetically responsive control element.  
      Remote controller  1100  may be configured to produce an electromagnetic control signal having various characteristics, depending upon the intended application of the system. Design specifics of electrical circuitry, signal generator, and signal transmitter will depend upon the type of electromagnetic control signal. The design of circuitry and related structures for generation and transmission of electromagnetic signals can be implemented using tools and techniques known to those of skill in the electronic arts. See, for example, Electrodynamics of Continuous Media, 2nd Edition, by L. D. Landau, E. M. Lifshitz and L. P. Pitaevskii, Elsevier Butterworth-Heinemann, Oxford, especially but not exclusively pp. 1-13- and 199-222, which is incorporated herein by reference, for discussion of theory underlying the generation and propagation of electrical, magnetic, and electromagnetic signals.  
      Remote controller  1100  may be configured to produce an electromagnetic control signal having various characteristics, depending upon the intended application of the system. In some embodiments, a specific remote controller may be configured to produce only a specific type of signal (e.g., of a specific frequency or frequency band) while in other embodiments, a specific remote controller may be adjustable to produce a signal having variable frequency content. Signals may include components which contribute a DC bias or offset in some cases, as well as AC frequency components. Generation of radio frequency electromagnetic signals is described, for example, in the The ARRL Handbook for Radio Communications 2006, R. Dean Straw, Editor, published by ARRL, Newington, Conn., which is incorporated herein by reference. Electromagnetic signal generator  1112  may be capable of producing an electromagnetic control signal sufficient to activate an electromagnetically responsive control element of a delivery device located in an environment to change an effective concentration of a primary material in a delivery fluid within a fluid-containing structure of the delivery device; and an electromagnetic signal transmitter capable of wirelessly transmitting the electromagnetic control signal to the electromagnetically responsive control element of a delivery device in an environment. Signal transmitter  1114  may include a sending device which may be, for example, an antenna or waveguide suitable for use with an electromagnetic signal. Static and quasistatic electrical fields may be produced, for example, by charged metallic surfaces, while static and quasistatic magnetic fields may be produced, for example, by passing current through one or more wires or coils, or through the use of one or more permanent magnets, as known to those of skill in the art. As used herein, the terms transmit, transmitter, and transmission are not limited to only transmitting in the sense of radiowave transmission and reception of electromagnetic signals, but are also applied to wireless coupling and/or conveyance of magnetic signals from one or more initial locations to one or more remote locations.  
      The remote controller may be modified as appropriate for its intended use. For example, it may be configured to be wearable on the body of a human (or other organism) in which a delivery device has been deployed, for example on a belt, bracelet or pendant, or taped or otherwise adhered to the body of the human. Alternatively, it may be configured to be placed in the surroundings of the organism, e.g., as a table-top device for use in a home or clinical setting.  
      In various embodiments, the delivery device may include a remote controller configured to generate a static or quasi-static electrical field control signal, a static or quasi-static magnetic field control signal, a radio-frequency electromagnetic control signal, a microwave electromagnetic control signal, an infrared electromagnetic control signal, a millimeter wave electromagnetic control signal, an optical electromagnetic control signal, or an ultraviolet electromagnetic control signal sufficient to activate the electromagnetically responsive control element to control the effective concentration of the primary material in the delivery fluid.  
      Various types of electromagnetic field control signals may be used to activate the electromagnetically responsive control element. The electromagnetically responsive control element may be responsive to a static or quasi-static electrical field or a static or quasi-static magnetic field. It may be responsive to various types of non-ionizing electromagnetic radiation, or in some cases, ionizing electromagnetic radiation. Electromagnetic field control signals that may be used in various embodiments include radio-frequency electromagnetic radiation, microwave electromagnetic radiation, infrared electromagnetic radiation, millimeter wave electromagnetic radiation, optical electromagnetic radiation, or ultraviolet electromagnetic radiation.  
      The electromagnetic signal generator may include electrical circuitry and/or a microprocessor. In some embodiments, the electromagnetic signal may be produced at least in part according to a pre-determined activation pattern. The remote controller may include a memory capable of storing the pre-determined activation pattern. In some embodiments, the electromagnetic signal may be produced based on a model-based calculation; the remote controller may include a memory capable of storing model parameters used in the model-based calculation.  
      In some embodiments, the remote controller may produce an electromagnetic signal having one or both of a defined magnetic field strength or defined electric field strength. In general, the term field strength, as applied to either magnetic or electric fields, may refer to field amplitude, squared-amplitude, or time-averaged squared-amplitude. The electromagnetic signal may have signal characteristics sufficient to produce a change in dimension of the electromagnetically responsive control element, a change in temperature of the electromagnetically responsive control element, a change in conformation of the electromagnetically responsive control element, or a change in orientation or position of the electromagnetically responsive control element. In some embodiments, the electromagnetic signal generator may include an electromagnet or electrically-polarizable element, or at least one permanent magnet or electret. The electromagnetic signal may be produced at least in part according to a pre-programmed pattern. The electromagnetic signal may have signal characteristics sufficient to produce a change in dimension in the electromagnetically responsive control element, the change in dimension causing a change in the concentration of the primary material within the delivery reservoir of the delivery device. It may have signal characteristics sufficient to produce a change in temperature of the electromagnetically responsive control element, the change in temperature causing a change in the concentration of the primary material within the delivery reservoir of the delivery device. In some embodiments, it may have signal characteristics sufficient to produce a change in one or more of shape, volume, surface area or configuration of the electromagnetically responsive control element, the change in dimension in one or more of shape, volume, surface area or configuration of the electromagnetically responsive control element causing a change in the concentration of the primary material within the delivery reservoir of the delivery device. The electromagnetic signal may have signal characteristics sufficient to produce a change in shape in an electromagnetically responsive control element including a shape memory material, a bimetallic structure, or a polymeric material. The electromagnetic signal may have a defined magnetic field strength or spatial orientation, or a defined electric field strength or spatial orientation.  
      In some embodiments, the remote controller may be configured to generate and transmit an electromagnetic control signal having at least one of frequency and orientation that are selectively receivable by the at least one magnetically responsive control element. In some embodiments, the remote controller may include at least one of hardware, software, or firmware configured to perform encryption of electromagnetic control signal to produce an encrypted electromagnetic control signal.  
       FIG. 29  depicts an example of an electromagnetic waveform of a type that may be used to activate and electromagnetically responsive control element. In plot  1150 , time is plotted on axis  1152 , and electromagnetic field strength is plotted on axis  1154 . Trace  1156  has the form of a square wave, switching between zero amplitude and a non-zero amplitude, A.  
       FIG. 30  depicts another example of an electromagnetic waveform. In plot  1200 , time is plotted on axis  1202 , and electromagnetic field strength is plotted on axis  1204 . Trace  1206  includes bursts  1208  and  1210 , during which the field strength varies between A and −A, at a selected frequency, and interval  1212 , during which field strength is zero.  
       FIG. 31  depicts another example of an electromagnetic waveform. In plot  1250 , time is plotted on axis  1252 , and electromagnetic field strength is plotted on axis  1254 . Trace  1256  includes bursts  1258 , and  1262 , during which the field strength varies between A and −A at a first frequency, and burst  1260 , during which the field strength varies between B and −B at a second (lower) frequency. Different frequencies may be selectively received by certain individuals or classes of electromagnetically responsive control elements within a device or system including multiple electromagnetically responsive control elements. An electromagnetic control signal may be characterized by one or more frequencies, phases, amplitudes, or polarizations. An electromagnetic control signal may have a characteristic temporal profile and direction, and characteristic spatial dependencies.  
      The magnetic or electric field control signal produced by the remote controller may have one or both of a defined magnetic field strength or a defined electric field strength. At low frequencies the electrical and magnetic components of an electromagnetic field are separable when the field enters a medium. Therefore, in static and quasi-static field application, the electromagnetic field control signal may be considered as an electrical field or a magnetic field. A quasi-static field is one that varies slowly, i.e., with a wavelength that is long with respect to the physical scale of interest or a frequency that is low compared to the characteristic response frequency of the object or medium; therefore, the frequency beyond which a field will no longer be considered ‘quasi-static’ is dependent upon the dimensions or electrodynamic properties of the medium or structure(s) influenced by the field.  
      As depicted in various embodiments, e.g., as shown in  FIGS. 6A-10B , the delivery reservoir may include an outlet through which the delivery fluid moves into an environment, for example by pumping or diffusion. In other embodiments, as depicted in  FIG. 32 , a delivery system  1300  may include a downstream fluid handling structure  1302  in fluid communication with the delivery reservoir  1304  and configured to receive fluid  1306  ejected from the delivery reservoir  1304  in response to the change in at least one of pressure or volume in the delivery reservoir  1304 . The downstream fluid handling structure  1302  may include a chamber, as depicted in  FIG. 32 . Delivery device  1300  may also include a pump (e.g., and osmotic pump  1308 ) and an electromagnetically responsive control element  1310 .  
      In other embodiments, e.g. delivery device  1350  shown in  FIG. 33 , a downstream fluid handling structure  1352  may include one or more channels  1354 , chambers  1356 , splitters  1358 , mixers  1360 , or other fluid handling structures, or various combinations thereof. Delivery device  1350  also includes pump  1362 , delivery reservoir  1364 , and outlet  1366 . Examples of fluid handling structures suitable for use in selected embodiments are described in U.S. Pat. Nos. 6,146,103 and 6,802,489, and in Krauβ et al., “Fluid pumped by magnetic stress”; Bearing a date of Jul. 1, 2004; pp. 1-3; located at: http://arxiv.org/PS_cache/physics/pdf/0405/0405025.pdf, all of which are incorporated herein by reference. Fluid handling structures may include, but are not limited to, channels, chambers, valves, mixers, splitters, accumulators, pulse-flow generators, and surge-suppressors, among others.  
      Previously described embodiments of delivery devices have include a delivery reservoir that is substantially chamber-like in shape. However, delivery fluid may be contained in fluid-containing structures having various shapes and configurations.  FIG. 34  illustrates a delivery device  1400  that includes a fluid-containing structure  1402  that takes the form of a channel. The fluid-containing structure  1402  may have at least one outlet  1404  through which a fluid may exit the fluid-containing structure  1402  to a downstream location; a delivery fluid  1406  contained within the fluid-containing structure  1402 ; a primary material contained within the fluid-containing structure and having a controllable effective concentration in the delivery fluid; at least one electromagnetically responsive control element adapted  1408  for controlling the distribution of the primary material between a first active form  1410  carried in the delivery fluid and a second form  1412  in response to an incident electromagnetic control signal, the effective concentration being the concentration of the first active form in the delivery fluid; and a pump  1414  configured for pumping delivery fluid from the fluid-containing structure to the downstream location.  
      As noted previously, delivery devices as described herein may include various types of pumps. A pump suitable for use in a delivery device may include a mechanical pump, a displacement pump, a centrifugal pump, or a peristaltic pump. The choice of pump and method of construction thereof may depend upon the intended use of the delivery device, the delivery site, the dimensions of the delivery device, among other factors, as will be apparent to those of skill in the art. In some embodiments, the downstream location may be an environment. In some embodiments, the downstream location may be a downstream fluid handling structure, and in some embodiments, the downstream location may include a downstream environmental interface. An environmental interface may function to facilitate the distribution of a primary material into an environment.  
       FIG. 35  depicts an example of a delivery device  1450  including an environmental interface  1452 . In the example of  FIG. 35 , the environmental interface  1452  provides for the delivery of primary material  1454  into blood flowing through capillaries  1456 . Delivery device  1450  includes pump  1458  and a fluid-containing structure  1460  (here depicted as a delivery reservoir) containing delivery fluid  1462  carrying primary material  1454 . Environmental interface  1452  includes substrate material  1464  capable of supporting growth of capillaries  1456 . Distribution channel  1466  distributes delivery fluid  1462  to substrate material  1464 , where primary material  1454  may diffuse into capillaries  1456  and be picked up by the blood.  
      In other embodiments, a delivery device as depicted generally in  FIG. 34  may include any of various types of downstream fluid handling structures. The downstream fluid handling structure may include at least one channel, of the type depicted in  FIG. 33 , or at least one chamber, for example as depicted in FIGS.  32  or  33 . The downstream fluid handling structure may include at least one mixer (e.g.  1360  in  FIG. 33  or at least one splitter (e.g.  1354  in  FIG. 33 ). In some embodiments, the downstream fluid handling structure may include a filter, for example, of the type depicted in  FIG. 6D ; it is contemplated that one or more filter may be placed at various downstream locations, not only at the outlet of the fluid-containing structure but potentially further downstream instead, or in addition.  
       FIG. 36  depicts a method of delivery a fluid through the use of a delivery device as described herein. The basic method includes receiving an electromagnetic control signal from a remote controller at step  1502 ; and responsive to the electromagnetic control signal, modifying an effective concentration of a primary material in a delivery fluid within a delivery reservoir at step  1504 .  
      As shown in  FIG. 37 , an expanded version of the method may include receiving an electromagnetic control signal from a remote controller at step  1552 ; and responsive to the electromagnetic control signal, modifying an effective concentration of a primary material in a delivery fluid within a delivery reservoir at step  1554 ; followed by an additional step of  1556  of ejecting the delivery fluid from the delivery reservoir.  
       FIG. 38  provides further detail on a method including receiving an electromagnetic control signal from a remote controller at step  1602 ; and responsive to the electromagnetic control signal, modifying an effective concentration of a primary material in a delivery fluid within a delivery reservoir at step  1604  (comparable to steps  1502  and  1504  as shown in  FIG. 36 ). The method may include modifying the effective concentration of the primary material in the delivery fluid by modifying at least one characteristic of the delivery fluid, the effective concentration of the primary material in the delivery fluid dependent upon the at least one characteristic of the delivery fluid, as shown in alternative step  1608  in  FIG. 38 . In this and other figures boxes containing optional or alternative steps are surrounded by a dashed line. The at least one characteristic may include, for example, temperature, pH, polarity, osmolality or chemical activity. As another alternative, as indicated at alternative step  1612  in  FIG. 38 , the method may include modifying the effective concentration of the primary material in the delivery fluid by modifying at least one characteristic of the primary material, the solubility of the primary material in the delivery fluid being dependent upon the at least one characteristic of the primary material. The at least one characteristic includes temperature, charge, polarity, osmolality, conformation, orientation, or chemical activity. As a further alternative, indicated at  1610  in  FIG. 38 , the method may include modifying the effective concentration of the primary material in the delivery fluid by modifying at least one of a number of interaction sites in the delivery reservoir or an affinity of at least one interaction site in the delivery reservoir for the primary material. The affinity of the at least one interaction site for the primary material may be modified by modifying the temperature, charge, polarity, osmolality, surface energy, orientation, conformation, chemical activity or chemical composition of the at least one interaction site or in the vicinity of the at least one interaction site. The number of interaction sites may be modified by stretching, compressing, unfolding, or changing a conformation of at least a portion of the delivery reservoir, for example.  
      A method as shown in  FIGS. 36-48  may include receiving the electromagnetic control signal with an electromagnetically responsive material, which may include, for example, a permanently magnetizable material, a ferromagnetic material, a ferrimagnetic material, a ferrous material, a ferric material, a dielectric or ferroelectric or piezoelectric material, a diamagnetic material, a paramagnetic material, and an antiferromagnetic material. The method may include a step of ejecting the delivery fluid into an environment, which may include, for example, the body of an organism, a body of water, or a contained fluid volume. Alternative, the method may include ejecting the delivery fluid into a downstream environmental interface or a downstream fluid-handling structure, which may include a channel, a chamber, a mixer, a separator, or combinations thereof.  
       FIG. 39  depicts a delivery system  1650  that includes a delivery device  1652  and a remote controller  1654 . Delivery device  1652  includes fluid-containing structure  1656  having at least one outlet  1658  through which fluid may exit the fluid-containing structure  1656 ; a delivery fluid  1660  contained within the fluid-containing structure  1656 ; a primary material  1662  contained within the fluid-containing structure  1656  and having a controllable effective concentration in the delivery fluid  1660 ; and at least one electromagnetically responsive control element  1664  adapted for modifying the distribution of the primary material  1662  between a first active form carried in the delivery fluid and a second form in response to an incident electromagnetic control signal to modify the effective concentration of the primary material in the delivery fluid, the effective concentration being the concentration of the first active form in the delivery fluid. Remote controller  1654  includes an electromagnetic signal generator  1668  capable of producing an electromagnetic control signal sufficient to activate the electromagnetically responsive control element  1664  of the delivery device  1652  located in an environment  1653  to change the effective concentration of the primary material in the delivery fluid  1660  within the fluid-containing structure  1656  of the delivery device  1652 ; and an electromagnetic signal transmitter  1670  capable of wirelessly transmitting the electromagnetic control signal  1672  to the electromagnetically responsive control element of the delivery device in the environment. The remote controller may include electrical circuitry  1674 , which may include at least one of hardware, firmware, or software configured to control generation of the electromagnetic control signal. The remote controller  1654  may include an electromagnetic signal generator  1668  configured to generate a static or quasi-static electrical field control signal, a static or quasi-static magnetic field control signal, a radio-frequency electromagnetic control signal sufficient, a microwave electromagnetic control, an infrared electromagnetic control signal, a millimeter wave electromagnetic control signal, an optical electromagnetic control signal, or an ultraviolet electromagnetic control signal sufficient to activate the electromagnetically responsive control element to control the effective concentration of the primary material within the fluid-containing structure. The remote controller may include an electromagnetic signal generator configured to generate a rotating electromagnetic control signal.  
      Delivery device  1652  may include a body structure  1676  adapted for positioning in an environment  1653  selected from a body of an organism, a body of water, or a contained fluid volume. For example, body structure  1676  may be adapted for positioning in a contained fluid volume selected from an industrial fluid volume, an agricultural fluid volume, a swimming pool, an aquarium, a drinking water supply, a potable water supply, and an HVAC system cooling water supply. Delivery device  1652  may include a pump  1678 , as described generally elsewhere herein.  
      The electromagnetically responsive control element  1664  may include a magnetically or electrically active material including at least one permanently magnetizable material, ferromagnetic material, ferrimagnetic material, ferrous material, ferric material, dielectric material, ferroelectric material, piezoelectric material, diamagnetic material, paramagnetic material, metallic material, orantiferromagnetic material. In some embodiments, the electromagnetically responsive control element may include a polymer, ceramic, dielectric, metal, shape memory material, or a combination of a polymer and a magnetically or electrically active component.  
       FIG. 40  depicts a delivery system  1700 , including remote controller  1702 , and delivery device  1704 . Delivery device  1704  includes fluid-containing structure  1656 , having outlet  1658  and containing delivery fluid  1660  and primary material  1662 . Delivery device  1704  also includes electromagnetically responsive control element  1664  for controlling the effective concentration of primary material  1662  in delivery fluid  1660 . Delivery device  1704  may include body structure  1676  adapted for placement in environment  1653 , and pump  1678 . Delivery device  1704  may also include RFID  1700 . Remote controller  1702  includes RF interrogation signal generator  1706  for generating an RF interrogation signal  1708 , which may be tuned to the RFID. Remote controller  1702  includes electromagnetic signal generator  1668 , electromagnetic signal transmitter  1670 , electrical circuitry  1674 , which function generally as described in connection with  FIG. 39 .  
       FIG. 41  illustrates a delivery system including a remote controller  1850  that produces electromagnetic control signal  1852  that is transmitted to delivery device  1854  in environment  1856 . Electromagnetic control signal  1852  is received by electromagnetically responsive control element  1858  in delivery device  1854 . Remote controller  1850  may include a signal input  1851  adapted for receiving a feedback signal  1860  sensed from an environment  1856  by a sensor  1862 , wherein the electromagnetic signal  1852  is produced based at least in part upon the feedback signal  1860  sensed from the environment. For example, the feedback signal  1852  may correspond to the osmolality or the pH of the environment, the concentration or chemical activity of a chemical in the environment, a temperature or pressure of the environment, or some other sensed signal. Remote controller  1850  may include electrical circuitry  1864 , signal generator  1866 , signal transmitter  1868 , and memory  1870 . Feedback from sensor  1862  may be sent over a wire connection or, in some embodiments, transmitted wirelessly. Remote controller may include a signal input adapted for receiving a feedback signal corresponding to one or more parameters sensed from the environment, wherein the electromagnetic control signal is produced based at least in part upon the feedback signal sensed from the environment. For example, the feedback signal corresponds to the concentration or chemical activity of a chemical in the environment.  
       FIG. 42  illustrates another embodiment of a delivery system, including remote controller  1900 , which transmits electromagnetic control signal  1902  to delivery device  1904  in environment  1906 . Remote controller  1900  may include a signal input  1908  adapted for receiving a feedback signal  1912  from sensor  1910  in delivery device  1904 . Electromagnetic control signal  1902  may be produced based at least in part upon the feedback signal  1912  corresponding to one or more parameters sensed from the delivery device. In some embodiments, the feedback signal may correspond to the concentration or chemical activity of a chemical within or around the delivery device. In some embodiments, the feedback signal from the delivery device may correspond to the osmolality or the pH within or around the delivery device, the concentration or chemical activity of a chemical within or around the delivery device, a temperature or pressure within or around the delivery device, the pumping rate of the delivery device, or some other parameter sensed from the delivery device. In others, the feedback signal may correspond to the pumping rate of the delivery device, produced, for example, by pump  1922 . In some embodiments, sensor  1910  may be configured for detecting at least one parameter from at least a portion of an environment surrounding the delivery device. The electromagnetic signal  1902  may be determined based at least in part upon the feedback signal  1912 . Examples of sensors are described in U.S. Pat. No. 6,935,165, and U.S. Patent Publication 2004/0007051, both of which are incorporated herein by reference. Delivery device  1904  includes electromagnetically responsive control element  1920 . Feedback signal  1912  may be transmitted wirelessly back to remote controller  1900 . Remote controller  1900  may include processor  1914 , signal generator  1916 , signal transmitter  1918 , and memory  1924 .  
      As illustrated in  FIG. 43 , in some embodiments, the remote controller may be configured to receive user input of control parameters. Remote controller  1950  includes input  1960  for receiving input of information or instructions from a user such as, for example, commands, variables, durations, amplitudes, frequencies, waveforms, data storage or retrieval instructions, patient data, etc. As in the other embodiments, remote controller  1950  transmits electromagnetic control signal  1952  to delivery device  1954  in environment  1956 , where it activates electromagnetically responsive control element  1958 . Input  1960  may include one or more input devices such as a keyboard, keypad, microphone, mouse, etc. for direct input of information from a user, or input  1960  may be any of various types of analog or digital data inputs or ports, including data read devices such as disk drives, memory device readers, and so forth in order to receive information or data in digital or electronic form. Data or instructions entered via input  1960  may be used by electrical circuitry  1962  to modify the operation of remote controller  1950  to modulate generation of an electromagnetic control signal  1952  by signal generator  1964  and transmission of the control signal  1952  by transmitter  1966 .  
       FIG. 44  illustrates a delivery system that includes a plurality of delivery devices, where two or more of the plurality of delivery devices are controlled by the remote controller. A delivery device may include a plurality of selectively activatable control elements, each associated with a particular fluid handling element, which may thus be controlled to perform multiple fluid-handling or reaction steps in a particular sequence. It is also contemplated that a delivery system may include a plurality of delivery devices which may be of the same or different types. As shown in  FIG. 44 , a delivery system  2000  may include a plurality of identical delivery devices  2002  distributed throughout an environment  2004  in order to perform a particular chemical reaction or process at a plurality of locations within the environment, and controlled by a remote controller  2006 . Alternatively, a delivery system may include a plurality of different delivery devices at different locations within an environment, each performing or controlling a reaction suited for the particular location. The invention as described herein is not limited to devices or systems including any specific number or configuration of electromagnetically responsive control elements within a delivery device, or specific number or configuration of delivery devices or remote controllers within a delivery system. Depending upon the particular application of a system, electromagnetically responsive control elements and/or delivery devices may be controlled in a particular pattern to producing a desired distribution of a delivery material in an environment. Control of such systems may be performed with the use of suitable hardware, firmware, software, through one or a plurality of remote controllers.  
      The remote controller used in the system depicted in  FIG. 44  may include an electromagnetic signal generator capable of producing an electromagnetic control signal sufficient to activate electromagnetically responsive control elements in a plurality of delivery devices located in an environment to change an effective concentration of primary material in a delivery fluid within a fluid-containing structure of each of the devices. In a related embodiment, the remote controller may include a plurality of signal inputs adapted for receiving signals from the plurality of delivery devices, the plurality of signal inputs coupled to a microprocessor configured to generate the electromagnetic control signal based upon the plurality of signals.  
      Selective activation or control of electromagnetically responsive control elements may be achieved by configuring electromagnetically responsive control elements to be activated by electromagnetic control signals having particular signal characteristics, which may include, for example, particular frequency, phase, amplitude, temporal profile, polarization, and/or directional characteristics, and spatial variations thereof. For example, different control elements may be responsive to different frequency components of a control signal, thereby allowing selective activation of the different control elements. The remote controller may be configured to produce a rotating electromagnetic signal, the rotating electromagnetic signal capable of activating the two or more delivery devices independently as a function of the orientation of the rotating electromagnetic signal.  
      As shown in  FIG. 45 , in still other embodiments, a delivery system  2050  may include a delivery device  2052  that includes a plurality of electromagnetically responsive control elements  2054 , responsive to one or more remote controller  2056 . A plurality of control elements  2054  may be used, for example, to control a plurality of locations or functions in delivery device  2052 .  
      As shown in  FIG. 46 , in some embodiments, a delivery system  2101  or may include a plurality of delivery devices  2102 ,  2104 ,  2106 , and  2108 , and a plurality of remote controllers  2100 a,  2100 b,  2100 c. As shown in  FIG. 46 , each delivery device may be controlled by one or more control signals produced in a distributed fashion by two or more of the plurality of remote controllers  2100   a - 2100   c.    
      As shown in  FIG. 47 , in some embodiments a delivery system  2151  may include a plurality of delivery devices  2152   a,    2152   b,  and  2152   c  and a plurality of remote controllers  2150   a,    2150   b,  and  2150   c,  each delivery device may be controlled by a separate remote controller, for example delivery device  2152   a  controlled by remote controller  2150   a,  delivery device  2152   b  controlled by remote controller  2150   b,  and delivery device  2152   c  controlled by remote controller  2150   c.    
      In still other embodiments, as shown in  FIG. 48 , a remote controller  2200  may include a plurality of transmission channels  2204   a,    2204   b,    2204   c,  and  2204   d,  for example (more or fewer channels may be used, without limitation). Remote controller  2200  may also include channel allocation hardware or software  2206  configured to allocate usage of the plurality of transmission channels  2204   a - 2204   d  for the transmission of the electromagnetic control signal from signal transmitter  2208  to selected delivery devices of the plurality of delivery devices  2202   a - 2202   f.    
      In another embodiment of a delivery system  2250  shown in  FIG. 49 , the remote controller  2252  may include encryption hardware or software  2262  configured to encrypt one or more control signal components, wherein the encrypted one or more control signal components are receivable by a delivery device  2254  including a corresponding decryption key  2264 . Remote controller  2252  may include signal generator  2256 , signal transmitter  2258 , and electrical circuitry  2260 , as described generally elsewhere.  
      In another embodiment of a delivery system  2300  shown in  FIG. 50 , the remote controller  2302  may include authentication hardware or software  2312  configured to perform an authentication procedure with a delivery device  2304 , wherein the remote controller  2302  is configured to produce activation of the electromagnetically responsive control element  2316  of an authenticated delivery device but not the electromagnetically responsive control element of a non-authenticated delivery device. Again, remote controller  2302  may include signal generator  2306 , signal transmitter  2308 , and electrical circuitry  2310 , as described generally elsewhere, and authentication portion  2314 , which may include hardware, firmware or software configured for performing an authentication protocol with remote controller  2302 .  
      Referring back to  FIG. 40 , remote controller  1702  may include an interrogation signal generator  1706  for generating a transmittable RFID interrogation signal. The remote controller may also include an interrogation signal transmitter for transmitting the transmittable RFID interrogation signal; an interrogation signal receiver for receiving a returned RFID interrogation signal from an RFID in a delivery device; and RFID detection circuitry configured to detect the presence of a selected RFID from a returned RFID interrogation signal. Upon detection of the presence of the selected RFID, to remote controller  1702  may generate and transmit a control signal configured for receipt by the delivery device including the selected RFID.  
      In various embodiments of the remote controller described herein, the generated electromagnetic control signal may have a defined magnetic field strength, or alternatively, or in addition, a defined electric field strength. Depending upon the intended application, the electromagnetic control signal may have signal characteristics sufficient to produce a change in dimension of the electromagnetically responsive control element, a change in temperature of at least a portion of the electromagnetically responsive control element, a change in conformation or configuration of the electromagnetically responsive control element, or a change in orientation or position of the electromagnetically responsive control element. The remote controller may include an electromagnetic signal generator that includes an electromagnet or electrically-polarizable element, or at least one permanent magnet or electret.  
       FIG. 51  depicts the steps of a method of delivering a material, comprising delivering an electromagnetic distribution control signal to an environment containing a delivery device, the delivery device including an electromagnetically responsive control element and a fluid-containing structure containing a delivery fluid and a quantity of a primary material distributed between a first active form carried in the delivery fluid and a second form according to a first distribution, the primary material distributed according to the first distribution having a first effective concentration in the delivery fluid equal to the concentration of the first active form in the delivery fluid, the electromagnetic distribution control signal having signal characteristics receivable by the electromagnetically responsive control element and sufficient to produce a change in the distribution of the primary material between the first active form and the second form to a second distribution, the primary material distributed according to the second distribution having a second active concentration in the delivery fluid, at step  2352 ; and delivering an electromagnetic delivery control signal to the environment containing the delivery device, the electromagnetic delivery control signal sufficient to produce pumping of the delivery fluid out of the fluid-containing structure, the delivery fluid containing the primary material at the second effective concentration in the delivery fluid at step  2354 .  
       FIG. 52  shows further variations of the method of  FIG. 51 . The method of  FIG. 52  include steps of delivering and electromagnetic distribution control signal at step  2402  and delivering an electromagnetic delivery control signal at step  2404  (e.g., as in  FIG. 51 ), followed by a step of generating an electromagnetic control signal according to a number of optional steps. For example, the method may include generating and transmitting the electromagnetic control signal to the delivery device with a remote controller, as shown at  2406   a.  Alternatively, the method may include generating a first electromagnetic control signal sufficient to produce a change in effective concentration of a primary material in a delivery fluid in a delivery reservoir of a delivery device; and generating a second electromagnetic control signal sufficient to cause delivery fluid containing primary material in solution to be released from the delivery reservoir into the environment, as shown at  2406   b.  Or, the method may include generating a first electromagnetic control signal having frequency and magnitude sufficient to produce heating of a heating element in or near the delivery reservoir, as shown at  2406   c.  Alternatively, the method may include generating a first electromagnetic control signal having frequency and magnitude sufficient to produce cooling of a cooling element in or near the delivery reservoir, as shown at  2406   d,  generating a first electromagnetic field having frequency and magnitude sufficient to produce a conformation change of a molecular structure, as shown at  2406   e,  or generating a first electromagnetic field having frequency and magnitude sufficient to produce a volume change of a material a molecular structure, as shown at  2406   f.    
       FIG. 53  shows a method of delivering a material including pumping a delivery fluid containing a primary material from a delivery reservoir of a delivery device to a downstream location at a first pumping rate at step  2452 ; and controlling the effective concentration of the primary material in the delivery fluid in response to a remotely transmitted electromagnetic control signal at step  2454 . In some embodiments, the first pumping rate may be a constant pumping rate. In some embodiment, the method may include varying the rate of delivery of the primary material to the downstream location by varying the effective concentration of the primary material in the delivery fluid in response to the remotely transmitted electromagnetic control signal. In other embodiments, the first pumping rate may be a time-varying pumping rate. In such embodiments, the method may include controlling the rate of delivery of the primary material to the downstream location by controlling both the effective concentration of the primary material in the delivery fluid and the pumping rate. The first pumping rate is modifiable in response to a remotely transmitted electromagnetic control signal, for example. The method may include controlling the effective concentration of the primary material in the delivery fluid through activation of an electromagnetically responsive control element in the delivery device by the remotely transmitted electromagnetic control signal, for example by heating of the electromagnetically responsive control element, cooling of the electromagnetically responsive control element. In some variants of the method, activation of the electromagnetically responsive control element may include a change in at least one dimension of the electromagnetically responsive control element, a change in orientation of the electromagnetically responsive control element, or a change in conformation of the electromagnetically responsive control element.  
       FIG. 54  shows a method of delivering a material, including receiving a first electromagnetic control signal with a first electromagnetically responsive control element in a delivery device, the delivery device including a fluid-containing structure containing a delivery fluid and a primary material distributed between a first active form carried in the delivery fluid and a second form, the primary material having a first effective concentration in the delivery fluid equal to the concentration of the first active form in the delivery fluid at step  2502 ; responsive to receipt of the first electromagnetic control signal by the first electromagnetically responsive control element, modifying the distribution of the primary material between the first active form and the second form, the primary material having a second effective concentration in the delivery fluid following the modification of the distribution of the primary material between the first active form and the second form at step  2504 ; and pumping the delivery fluid containing the primary material at the second effective concentration from the fluid-containing structure of the delivery device to a downstream location at step  2506 . In the method of  FIG. 54 , the primary material has a different stability in the first active form than in the second form, a different immunogenicity in the first active form than in the second form, a different reactivity in the first active form than in the second form, or a different activity in the first active form than in the second form.  
      In a variant of the method of  FIG. 54 , shown in  FIG. 55  (with steps  2552 - 2556  the same as steps  2502 - 2506 ), the method may include the additional step of filtering the second form of the primary material from the delivery fluid prior to pumping the delivery fluid containing the primary material at the second effective concentration from the fluid-containing structure of the delivery device to a downstream location  2558 .  
      In the method of  FIG. 54 , in some embodiments the first effective concentration may be lower than the second effective concentration, and some embodiments first effective concentration may be higher than the second effective concentration. The method may include modifying the rate of pumping of the delivery fluid to the downstream location responsive to receipt of a second electromagnetic control signal by a second electromagnetically responsive control element. In some embodiments, the first electromagnetic control signal and the second electromagnetic control signal may be the same electromagnetic control signal. In other embodiments, the first electromagnetic control signal may be different than the second electromagnetic control signal. In some embodiments, the first electromagnetically responsive control element and the second electromagnetically responsive control element may be the same electromagnetically responsive control element, while in other embodiments, the first electromagnetically responsive control element may be a different control element than the second electromagnetically responsive control element. “Different” control elements may be control elements of different types, or distinct control elements that are of the same type.  
       FIG. 56  depicts further variants on the method of  FIG. 54 . Steps  2602  through  2606  are the same as steps  2502 - 2506  in  FIG. 54 . Steps  2608   a - 2608   f  alternative steps for modifying the distribution of primary material between the first active form and the second form. Step  2608   a  includes modifying the distribution of primary material in response to receipt of the first electromagnetic control signal by modifying a pressure within the fluid containing structure, step  2608   b  includes modifying the distribution of primary material in response to receipt of the first electromagnetic control signal by modifying a temperature within the fluid containing structure, step  2608   c  includes modifying the distribution of primary material in response to receipt of the first electromagnetic control signal by modifying a volume of the fluid containing structure, step  2608   d  includes modifying the distribution of primary material in response to receipt of the first electromagnetic control signal by producing vibration within the fluid containing structure, step  2608   e  includes modifying the distribution of primary material in response to receipt of the first electromagnetic control signal by producing fluid mixing within the fluid containing structure, and step  2608   f  includes modifying the distribution of primary material in response to receipt of the first electromagnetic control signal by modifying a number of available interaction sites within the fluid containing structure, the available interaction sites capable of interacting with the primary material to produce the second form of the primary material.  
       FIG. 57  illustrates a method of delivering a material, including, at step  2652 , introducing a delivery device into an environment, the delivery device including an electromagnetically responsive control element, a pump, a fluid-containing structure containing a delivery fluid and a quantity of a primary material, the primary material being distributed between a first active form carried in the delivery fluid and a second form according to a first distribution in which the primary material has a first effective concentration in the delivery fluid equal to the concentration of the first active form in the delivery fluid, and wherein the electromagnetically responsive control element is configured to modify the distribution of primary material between the first active form and the second form, and a pump, the pump being activatable for pumping delivery fluid from the fluid-containing structure to a downstream location. At step  2654 , the method includes a step of delivering an electromagnetic distribution control signal to the environment with signal characteristics selectively receivable by the electromagnetically responsive control element and sufficient to produce a change in the distribution of the primary material between the first active form and the second from to a second distribution, the primary material distributed according to the second distribution having a second effective concentration in the delivery fluid. The pump may be activated to pump delivery fluid containing the primary material at the second effective concentration out of the fluid containing structure. In one variant, the pump may be activated prior to introducing the delivery device into the environment. In another variant, the pump may be activated upon introduction of the delivery device into the environment. In still another variant, the pump may be activated subsequent to introducing the delivery device into the environment. The method as depicted in  FIG. 57  may also include delivering an electromagnetic delivery control signal having signal characteristics selectively receivable by a second electromagnetically responsive control element in the delivery device to produce the pumping of the delivery fluid containing the primary material at the second effective concentration out of the fluid-containing structure. The primary material may have a different immunogenicity, reactivity, or stability when it is in the first active form than when it is in the second form.  
       FIG. 58  illustrates a method of controlling a delivery device, which includes the steps of generating an electromagnetic control signal including frequency components absorbable by an electromagnetically responsive control element of a delivery device in an environment, the delivery device including a fluid-containing structure containing a delivery fluid and a quantity of primary material, the primary material being distributed between a first active form and a second form and having an effective concentration in the delivery fluid equal to the concentration of the first active form in the delivery fluid, wherein the effective concentration of the primary material in the delivery fluid is controllable by the electromagnetically responsive control element at  2702 ; and remotely transmitting the electromagnetic control signal to the delivery device with signal characteristics sufficient to activate the electromagnetically responsive control element in the delivery device to control the effective concentration of primary material in the delivery fluid in the delivery device at  2704 .  
       FIG. 59  illustrates an expansion of the method shown in  FIG. 58 , with steps  2752  and  2754  being the same as steps  2702  and  2704 , respectively, in  FIG. 58 , with a number of alternative steps relating to generation of the electromagnetic control signal. Step  2756   a  includes generating the electromagnetic control signal and transmitting the electromagnetic control signal to the delivery device with a remote controller. Step  2756   b  includes generating the electromagnetic control signal and transmitting the electromagnetic control signal to the delivery device with two or more remote controllers. Step  2756   c  includes generating the electromagnetic control signal from a model-based calculation. Step  2756   d  includes generating the electromagnetic control signal based on a stored pattern. As yet another alternative, step  2756   e  includes generating the electromagnetic control signal based upon a feedback control scheme. A feedback control scheme may be, for example, a variable feedback control scheme.  
      A further expansion the method shown in  FIG. 58  may include the additional steps depicted in  FIG. 60 , namely receiving a feedback signal corresponding to one or more parameters sensed from the environment at  2802 ; and based upon the feedback signal, generating the electromagnetic control signal with signal characteristics expected to produce a desired feedback signal, at  2804 . In some embodiments, receiving the feedback signal from the environment may include receiving signals from at least one sensor in the environment, while in other embodiments it may include receiving the feedback signal from the environment includes receiving signals from two or more sensors in the environment. Receiving the feedback signal from the environment may include receiving a measure of the concentration or chemical activity of a chemical within at least a portion of the environment.  
      In another variation of the method shown in  FIG. 58 , shown in  FIG. 61 , the method may include the additional steps of receiving a feedback signal from the delivery device at  2852 ; and based upon the feedback signal, generating an electromagnetic control signal having signal characteristics that are expected to produce a desired feedback signal at  2854 . Receiving a feedback signal from the delivery device may include receiving signals from at least one sensor in the delivery device, or alternatively, receiving a feedback signal from the delivery device may include receiving signals from two or more sensors in the delivery device. For example, receiving the feedback signal from the delivery device may include receiving a signal representing a concentration or chemical activity of a chemical within or around the delivery device.  
      Another variation of the method depicted in  FIG. 58 , shown in  FIG. 62 , may include the additional steps of receiving user input of one or more control parameters at  2892 ; and based upon the one or more control parameters, generating an electromagnetic control signal having signal characteristics expected to produce a desired effective concentration of primary material in the delivery fluid, as  2894 . The desired effective concentration of primary material in the delivery fluid may be an effective concentration sufficient to produce a desired rate of delivery of the first active form of the primary material to the environment by the delivery device.  
      Further additions to the method depicted in  FIG. 58  include steps of activating the electromagnetically responsive control element to produce heating or cooling, or activating the electromagnetically responsive control element to produce a change in configuration of the electromagnetically responsive control element. Steps of generating an electromagnetic control signal and remotely transmitting the electromagnetic control signal to the delivery device, as shown in  FIG. 58 , may be performed according to instructions provided in the form of software, hardware or firmware. In some method embodiments, the steps of generating an electromagnetic control signal and remotely transmitting the electromagnetic control signal to the delivery device may be performed according to instructions distributed among a plurality of controllers or transmitters.  
      Generating the electromagnetic control signal includes generating a static or quasi-static magnetic field, static or quasi-static electrical field, radio-frequency electromagnetic signal, microwave electromagnetic signal, millimeter wave electromagnetic signal, optical electromagnetic signal, which may be an optical electromagnetic signal is an infrared electromagnetic signal, or generating an ultraviolet electromagnetic signal. Generating the electromagnetic control signal may be performed under software control.  
       FIG. 63  depicts a further variation of the method shown in  FIG. 58 , with steps  2902  and  2904  corresponding to steps  2702  and  2704 , respectively. The method includes the additional step of modifying the concentration of the primary material within the delivery fluid in the fluid-containing structure of the delivery device by modifying the area of an interaction region within the fluid containing structure of the delivery device at  2906 . Modifying the area of the interaction region includes increasing the area of the interaction region, as at  2906   a,  or alternatively, decreasing the area of the interaction region, as  2906   b.  In the case that the area is increased, and the interaction region includes interaction sites, and increasing the area of the interaction region may include increasing the distances between interaction sites in the interaction region, as at  2908   a,  or increasing the area of the interaction region includes increasing a number of interaction sites in the reaction area, as at  2908   b.  In the case that the area is decreased, as at  2906   b,  and the interaction region includes interaction sites, decreasing the area of the interaction region may include decreasing distances between one or more interaction sites in the interaction region, as at  2910   a,  or decreasing a number of interaction sites in the reaction area as at  2910   b.    
       FIG. 64  depicts a further variation of the method shown in  FIG. 58 , with steps  2952  and  2954  corresponding to steps  2702  and  2704 , respectively. The method further includes a further step of modifying the concentration of the primary material in the delivery fluid by modifying a condition at an interaction region within the fluid-containing structure, at  2956 . Modifying a condition at the interaction region may include heating or cooling at least a portion of the interaction region, as shown at  2958   a,  modifying the osmolality or the pH of at least a portion of the interaction region, at  2958   b,  modifying the surface charge of at least a portion of the interaction region, at  2958   c,  or modifying the surface energy of at least a portion of the interaction region, as  1958   d.    
      In another variation, shown in  FIG. 65 , the method includes a further step of modifying a condition at the interaction region by modifying a condition within the fluid-containing structure, as indicated at step  3006  (steps  3002  and  3004  correspond to steps  2702  and  2704  in  FIG. 58 ). Modifying a condition within the fluid-containing structure may include modifying the volume of the fluid-containing structure, as shown at  3008   a,  heating or cooling at least a portion of the fluid-containing structure, as shown at  3008   b,  or modifying the osmolality or the pH within at least a portion of the fluid-containing structure, as shown at  3008   c.    
      Software may be used in performing various of the methods as described herein. Such software includes software for controlling delivery of a material from a delivery device, including instructions for generating an electromagnetic control signal including frequency components absorbable by an electromagnetically responsive control element of a delivery device in an environment, the delivery device including a fluid-containing structure containing a delivery fluid and a quantity of primary material, the primary material being distributed between a first active form and a second form and having an effective concentration in the delivery fluid equal to the concentration of the first active form in the delivery fluid, wherein the effective concentration of the primary material in the delivery fluid is controllable by the electromagnetically responsive control element; and instructions for controlling the transmission of the electromagnetic control signal to the delivery device with signal characteristics sufficient to activate the electromagnetically responsive control element in the delivery device to control the effective concentration of primary material in the delivery fluid in the delivery device.  
      The software may include instructions for generating the electromagnetic control signal include instructions for calculating the electromagnetic control signal based on a model. The instructions for generating the electromagnetic control signal may include instructions for generating the electromagnetic control signal based on a pattern stored in a data storage location, or instructions for generating the electromagnetic control signal based upon a feedback control algorithm. For example, the instructions for generating the electromagnetic control signal may include instructions for generating the electromagnetic control signal based upon a variable feedback control algorithm. The software may include instructions for receiving a feedback signal corresponding to one or more parameters sensed from the environment; and instructions for generating the electromagnetic control signal based at least in part upon the received feedback signal, the electromagnetic control signal having signal characteristics expected to produce a desired feedback signal. Some embodiments of the software may include instructions for receiving a feedback signal from the delivery device; and instructions for generating the electromagnetic control signal based at least in part on the received feedback signal, the electromagnetic control signal having frequency composition and amplitude expected to produce a desired feedback signal. In some embodiments, the software may include instructions for receiving user input of one or more control parameters; and instructions for generating the electromagnetic control signal based at least in part upon the one or more control parameters. In some embodiments, the software may include instructions for performing encryption of the electromagnetic control signal. Instruction may be included for performing an authentication procedure between a remote controller transmitting the electromagnetic control signal and a delivery device including the electromagnetically responsive control element intended to be activated by the electromagnetic control signal. At least a portion of the instructions generating the electromagnetic control signal and the instruction for controlling the transmission of the electromagnetic control signal are executable in distributed fashion on a plurality of microprocessors. Some embodiments of the software may include channel allocation instructions configured to control the allocation of control signal transmission channels for transmission of a plurality of control signals to a corresponding plurality of delivery devices.  
      With regard to the hardware and/or software used in the control of devices and systems according to the present embodiments, and particularly to the sensing, analysis, and control aspects of such systems, those having skill in the art will recognize that the state of the art has progressed to the point where there is little distinction left between hardware and software implementations of aspects of systems; the use of hardware or software is generally (but not always, in that in certain contexts the choice between hardware and software can become significant) a design choice representing cost vs. efficiency or implementation convenience tradeoffs. Those having skill in the art will appreciate that there are various vehicles by which processes and/or systems described herein can be effected (e.g., hardware, software, and/or firmware), and that the preferred vehicle will vary with the context in which the processes are deployed. For example, if an implementer determines that speed and accuracy are paramount, the implementer may opt for a hardware and/or firmware vehicle; alternatively, if flexibility is paramount, the implementer may opt for a solely software implementation; or, yet again alternatively, the implementer may opt for some combination of hardware, software, and/or firmware. Hence, there are several possible vehicles by which the processes described herein may be effected, none of which is inherently superior to the other in that any vehicle to be utilized is a choice dependent upon the context in which the vehicle will be deployed and the specific concerns (e.g., speed, flexibility, or predictability) of the implementer, any of which may vary.  
      The foregoing detailed description has set forth various embodiments of the devices and related processes or methods via the use of block diagrams, flowcharts, and/or examples. Insofar as such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, it will be implicitly understood by those with skill in the art that each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In one embodiment, several portions of the subject matter subject matter described herein may be implemented via Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), digital signal processors (DSPs), or other integrated formats. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein, in whole or in part, can be equivalently implemented in standard integrated circuits, as one or more computer programs running on one or more computers (e.g., as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as virtually any combination thereof, and that designing the circuitry and/or writing the code for the software and/or firmware would be well within the capabilities of one of skill in the art in light of this disclosure. In addition, those skilled in the art will appreciate that certain mechanisms of the subject matter described herein are capable of being distributed as a program product in a variety of forms, and that an illustrative embodiment of the subject matter described herein applies equally regardless of the particular type of signal bearing media used to actually carry out the distribution. Examples of a signal bearing media include, but are not limited to, the following: recordable type media such as floppy disks, hard disk drives, CD ROMs, digital tape, and computer memory; and transmission type media such as digital and analog communication links using TDM or IP based communication links (e.g., links carrying packetized data).  
      In a general sense, those skilled in the art will recognize that the various aspects described herein which can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or any combination thereof can be viewed as being composed of various types of “electrical circuitry.” Consequently, as used herein “electrical circuitry” includes, but is not limited to, electrical circuitry having at least one discrete electrical circuit, electrical circuitry having at least one integrated circuit, electrical circuitry having at least one application specific integrated circuit, electrical circuitry forming a general purpose computing device configured by a computer program (e.g., a general purpose computer configured by a computer program which at least partially carries out processes and/or devices described herein, or a microprocessor configured by a computer program which at least partially carries out processes and/or devices described herein), electrical circuitry forming a memory device (e.g., forms of random access memory), and/or electrical circuitry forming a communications device (e.g., a modem, communications switch, or optical-electrical equipment).  
      Those skilled in the art will recognize that it is common within the art to describe devices for detection or sensing, signal processing, and device control in the fashion set forth herein, and thereafter use standard engineering practices to integrate such described devices and/or processes into fluid handling and/or delivery systems as exemplified herein. That is, at least a portion of the devices and/or processes described herein can be integrated into a fluid handling and/or delivery system via a reasonable amount of experimentation.  
      Those having skill in the art will recognize that systems as described herein may include one or more of a memory such as volatile and non-volatile memory, processors such as microprocessors and digital signal processors, computational-supporting or—associated entities such as operating systems, user interfaces, drivers, sensors, actuators, applications programs, one or more interaction devices, such as data ports, control systems including feedback loops and control implementing actuators (e.g., devices for sensing osmolality, pH, pressure, temperature, or chemical concentration, signal generators for generating electromagnetic control signals). A system may be implemented utilizing any suitable available components, combined with standard engineering practices.  
      The foregoing-described aspects depict different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermediate components. Likewise, any two components so associated can also be viewed as being “operably connected”, or “operably coupled”, to each other to achieve the desired functionality.  
      While particular aspects of the present subject matter described herein have been shown and described, it will be obvious to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from this subject matter described herein and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this subject matter described herein. Furthermore, it is to be understood that the invention is defined by the appended claims. It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should NOT be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” and/or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense of one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense of one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together).  
      Although the methods, devices, systems and approaches herein have been described with reference to certain preferred embodiments, other embodiments are possible. As illustrated by the foregoing examples, various choices of remote controller, system configuration and fluid handling/delivery device may be within the scope of the invention. As has been discussed, the choice of system configuration may depend on the intended application of the system, the environment in which the system is used, cost, personal preference or other factors. System design, manufacture, and control processes may be modified to take into account choices of use environment and intended application, and such modifications, as known to those of skill in the arts of device design and construction, may fall within the scope of the invention. Therefore, the full spirit or scope of the invention is defined by the appended claims and is not to be limited to the specific embodiments described herein.  
      While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. It is intended that the various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.