Abstract:
A new and enhanced device and technique for mixing and dispensing a preserved agent is disclosed. The syringe-like device employs a novel piston fluid channel allowing for various chambers of the syringe to come into fluid communication when the piston is actuated. More especially, the person administering the preserved agent may visually confirm full resuspension and deliver an accurate dosage of the agent.

Description:
BACKGROUND 
       [0001]    The present invention relates to the mixing and dispensing of sensitive biological and bioactive materials, including, for example, preserved agents. More particularly, the invention concerns a device for the admixing of a powdered or otherwise preserved agent, such as a lyophilized drug, and a fluid through a specialized fluid channel in the piston of a syringe. This invention allows lyophilized agents such as Botox, Factor VIII, Immunoglobulin IgG, and many others to be delivered. Moreover these drugs can be stored and utilized without the need for syringes, complicated sterile technique, or professional training in the mixing of drugs in remote places such as on the battlefield or in rural areas. 
         [0002]    State of the art information relevant to attempts to address the problem of resuspension of a preserved agent prior to its delivery can be found in U.S. Pat. Nos. 4,941,876; 5,330,426; 5,531,683; 5,637,087; 5,785,682; and 6,387,074, as well as U.S. Publication Nos. 2004/0138611 and 2005/0075602, each of which is expressly incorporated by reference as if fully set forth herein. 
         [0003]    However, each of these references suffer from one or more of the following disadvantages: incomplete admixture of the fluid and the preserved agent, inaccurate dosage delivery of the resuspended agent, labor intensive devices, multiple sterile systems that increase the potential for compromises of sterile technique, and the inability to fully complete the admixing process in front of the patient. These various limitations make the present disclosure more desirable than the cited references, and are demonstrative of satisfaction of a longstanding need in the art addressed and overcome according to the teachings of the present disclosure. 
       SUMMARY 
       [0004]    The present disclosure serves as a simple solution to the myriad of formerly complicated solutions for the resuspension and delivery of preserved agents. The present system allows for simple loading and administration of preserved agents after resuspension in an appropriate fluid, which occurs completely within the device. This type of system is advantageous because it saves labor and reduces the probability of error inherent in multiple step processes involving systems with multiple needles, wipes for bottle tops, and other mistakes that potentially compromise sterility of the instrument and agent vehicle. Those skilled in the art will understand that any biological industrial product can be used with and is embraced by the instant disclosure. 
         [0005]    According to a feature of the present disclosure, a piston fluid channel is used to admix a fluid with a preserved agent prior to delivery of the agent to a patient. A preserved agent ampoule in a first position holds the preserved agent. The ends of the preserved agent ampoule are pierceable septa. Fluid is loaded into a fluid chamber in the dispenser body prior to placing the piston into the dispenser body. 
         [0006]    As force is applied to the piston via its plunger, a cannula on the end of the piston pierces the septum on the piston end of the preserved agent ampoule. The fluid is moved from a fluid chamber into a preserved agent ampoule chamber through a piston fluid channel and the piston cannula. A combination of at least one of compression force, a partial vacuum in the preserved agent ampoule chamber, or some combination of both causes the fluid to move through the piston fluid channel into the preserved agent ampoule chamber. 
         [0007]    Once in the preserved agent ampoule chamber, the fluid and the preserved agent admix to form a resuspended agent ready for delivery to a patient. The person operating an embodiment of the present disclosure can, at this point, visually confirm that the preserved agent has been fully resuspended in the fluid prior to final delivery. 
         [0008]    After resuspension of the preserved agent, additional force is applied to the piston by means of the plunger. This additional force moves the entire preserved agent ampoule into a second position, towards the interior end of the delivery cannula, which pierces the delivery end septum of the preserved agent ampoule and places the delivery cannula into the preserved agent ampoule chamber. In this position, the delivery cannula provides a channel to deliver the resuspended agent to the patient. 
         [0009]    Additional force applied to the piston moves the piston end septum of the preserved agent ampoule through the preserved agent ampoule towards the delivery end septum. The compression force within the preserved agent ampoule chamber forces the resuspended agent into the delivery cannula and into the patient. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0010]    The above-mentioned features and objects of the present disclosure will become more apparent with reference to the following description taken in conjunction with the accompanying drawings wherein like reference numerals denote like elements and in which: 
           [0011]      FIG. 1  is a longitudinal sectional view of an embodiment of the present disclosure showing a piston and preserved agent ampoule in their initial configuration prior to piercing of either a piston end or a delivery end septum. 
           [0012]      FIG. 2  is a longitudinal sectional view of an embodiment of the present disclosure during a piercing operation of a piston end septum by a piston cannula. 
           [0013]      FIG. 3  is a longitudinal sectional view of an embodiment of the present disclosure of a piston during an admixing process of a fluid and a preserved agent in a preserved agent ampoule chamber. 
           [0014]      FIG. 4  is a longitudinal sectional view of an embodiment of the present disclosure of the process with a piston moving a piston end septum towards a delivery end septum and delivering a resuspended agent through a delivery cannula. 
           [0015]      FIG. 5  is a longitudinal sectional view of an embodiment of the present disclosure wherein the piston cannula is a spike, which forms one part of a single-piece molded piston and cannula unit. 
           [0016]      FIG. 6  is a longitudinal sectional view of an embodiment with an adjustable cannula assembly allowing for variations in the volume of fluid delivered into a preserved agent ampoule chamber. 
           [0017]      FIG. 7  is a longitudinal sectional view of an embodiment with an adjustable cannula assembly allowing for variations in the volume of fluid delivered into a preserved agent ampoule chamber. 
           [0018]      FIG. 8  is a longitudinal sectional view of an embodiment of the process of adjusting an adjustable cannula assembly allowing for variations in the volume of fluid delivered into a preserved agent ampoule chamber. 
       
    
    
     DETAILED DESCRIPTION  
       [0019]    The present inventors discovered that certain biological, chemical, and pharmaceutical agents and compounds can be delivered via a novel piston fluid channel mechanism. According to embodiments of the present disclosure, piston fluid channel  121  allows for complete admixture of fluid  129  and preserved agent  107  within the container originally holding preserved agent  107 . Once preserved agent  107  is admixed with fluid  129 , resuspended agent  133  can then be delivered. 
         [0020]    Likewise disclosed is a novel enhanced syringe-style device wherein the instant disclosure describes a novel method for mixing and dispensing preserved agent  107 . 
         [0021]      FIG. 1  illustrates embodiments of aspects of an embodiment of the present disclosure in an initial configuration. The system comprises dispenser body  101  into which preserved agent ampoule  105  is inserted prior to insertion of fluid  129  and piston  115 . Piston  115  contains piston fluid channel  121  and piston cannula  119 , which together move fluid  129  from fluid chamber  123  into preserved agent ampoule chamber  113  for admixing of fluid  129  with preserved agent  107 . Thereafter, piston  115  provides the force by which resuspended agent  131  is delivered through delivery cannula  103 . 
         [0022]    Dispenser body  101  is an open-ended container with a delivery end and a piston end according to an embodiment of the present disclosure. Delivery end of dispenser body  101  narrows to an articulation point where delivery cannula  103  connects for delivery of resuspended agent  131 . Delivery cannula  103  can be a hypodermic needle or any other suitable dispensing structure as commonly known in the art. The interior end of delivery cannula  103  is either a part of cannula itself or a secondary structure, such as a spike, in fluid communication with delivery cannula  103  and providing a sealed channel in which resuspended agent  131  can be delivered. The interior end of delivery cannula  103  protrudes into the cavity of dispenser body  101  and pierces delivery end septum  109  of preserved agent ampoule  105  preparatory to delivery of resuspended agent  131 . 
         [0023]    According further to the illustrative example, preserved agent ampoule  105  is a hollow container with a delivery end and a piston end. Preserved agent ampoule  105  contains preserved agent  107 . The delivery end is sealed with delivery end septum  109 , which is made of a flexible material suitable to piercing by delivery cannula  103  as commonly known in the art. Delivery end septum  109  is fixed with respect to its position in preserved agent ampoule  105 . 
         [0024]    Preserved agent ampoule  105  contains preserved agent  107  and is inserted into dispenser body  101  through the opening in the piston end of dispenser body  101 . According to one version of the instant teachings, once inserted into dispenser body  101 , preserved agent ampoule  105  abuts a positioning protuberance, which are common in the art, contained within the inside surface of the delivery end of dispenser body  101 . The protuberance holds preserved agent ampoule  105  in a first position for the piercing of piston end septum  111  with piston cannula  119 . 
         [0025]    A sufficient force moves preserved agent ampoule  105  past the positioning protuberance and into a second position. Thus, the positioning protuberance gives sufficient friction to prevent movement of preserved agent ampoule  105  during piercing of piston end septum  111 , but not so much friction that additional force cannot move preserved agent ampoule  105 . The positioning protuberance can be made of any suitable material capable of holding preserved agent ampoule  105  in place when a weaker but sufficient force is exerted on preserved agent ampoule  105  allowing piston cannula  119  to pierce piston end septum  111 , but also permitting preserved agent ampoule  105  to move into a second position when a stronger force is exerted on it. The protuberance, in an exemplary embodiment, is a bearing-like member as commonly known in the art. Another embodiment is a positioning member, which holds preserved agent ampoule  105  in the first position. Positioning member extends from the inside to the outside of dispenser body  101 . After piston cannula  119  pierces piston end septum  111  and fluid  129  is moved into preserved agent ampoule chamber  113 , positioning member is removed and additional force exerted on preserved agent ampoule  105  moves it into the second position. 
         [0026]    According to exemplary embodiments, piston end septum  111  is made of a material suitable to form a tight seal with the inner walls of preserved agent ampoule  105 , but is also moveable within preserved agent ampoule  105  while maintaining the seal. The material is also suitable for piercing by piston cannula  119  as commonly known in the art. Piston end septum  111  should be made of a flexible material, such as rubber, so that the volume of fluid chamber  123  will not change during the piercing process. Alternately, a small pocket of air in fluid chamber  123  accomplishes the same objective. 
         [0027]    In an embodiment, piston end septum  111  is a two piece system comprised of a support piece that moves through preserved agent ampoule chamber  113  and a pierceable region, similar to bottle tops commonly known in the art. The support piece can be made of metal, plastic, or other materials suitable for being pushed through preserved agent ampoule chamber  113 . The support piece either forms a seal with the inner wall or walls of preserved agent ampoule  105  or has a separate sealing member connected. The pierceable region is made as previously described for piston end septum  111 . Moreover, the region must be large enough for piston cannula  119  to reliably pierce it. 
         [0028]    Piston end septum  111  forms a seal with preserved agent ampoule  105  via friction between piston end septum  111  and inner wall or walls of preserved agent ampoule  105 . Unlike delivery end septum  109 , piston end septum  111  is movable with respect to preserved agent ampoule  105 . Applied force to piston end septum  111  will move it through preserved agent ampoule chamber  113  towards delivery end septum  109  in the delivery process of resuspended agent  131 . 
         [0029]    In an illustrative embodiment, preserved agent ampoule  105  is sealed under vacuum conditions. The vacuum is intended to move fluid  129  from fluid chamber  123  to preserved agent ampoule chamber  113 , through piston fluid channel  121  and piston cannula  119 , in the absence of compression force. However, vacuum conditions are not necessary; fluid  129  can be moved from fluid chamber  123  into preserved agent ampoule  105  via compression of fluid chamber  123  by movement of piston  115  toward the delivery end of dispenser body  101 , which raises the internal pressure of fluid chamber  123 , consequently forcing fluid  129  through piston fluid channel  121  and piston cannula  119 , and into preserved agent ampoule chamber  113  as previously described. 
         [0030]    In an embodiment, dispenser body  101  and preserved agent ampoule  105  are made of a transparent material suitable to visual inspection of the mixing process. The person administering the agent can visually verify resuspension of preserved agent  107  into fluid  129 , ensuring that the complete dosage of preserved agent  107  resuspends into fluid  129 . Additionally, the entire process can be performed in front of the patient. 
         [0031]    Referring still to an illustrative embodiment in  FIG. 1 , piston  115  completes the assembly of the present disclosure as shown in an initial configuration. Plunger  117  connects to piston  115  and is actuated to apply force to piston  115  and move it through dispenser body  101 . Plunger  117  can be made of any material suitable for syringe plungers. 
         [0032]    When inserted into dispenser body  101 , at least one sealing member  133  of piston  115  articulates with the inner wall or walls of dispenser body  101  to form a seal. Each sealing member  133  is made of a suitable material, such as rubber, plastic, polymers, ePTFE, and the like, allowing for a tight seal between sealing member  133  and the inner wall or walls of dispenser body  101 . Each sealing member  133  also allows for movement of piston  115  when axial force is applied to piston  115 . Such movement does not break the seal between each sealing member  133  and the inner wall or walls of dispenser body  101 . 
         [0033]    Piston  115  also contains piston fluid channel  121 . Piston fluid channel opening  125  and piston cannula opening  127  are the end points of piston fluid channel  121 . Piston fluid channel  121  forms a sealed and continuous conduit between fluid chamber  123  and preserved agent ampoule chamber  113 . Thus, piston fluid channel  121  allows fluid  129  to flow from fluid chamber  123  to preserved agent ampoule chamber  113  when vacuum force or compressive force is applied to fluid chamber  123 . In an embodiment, piston fluid channel opening  125  is placed in a location where the entire volume of fluid  129  may be removed from fluid chamber  123  and moved into preserved agent ampoule chamber  113 . 
         [0034]    Piston cannula  119  extends from piston  115  and is used to pierce piston end septum  111 . In an embodiment, the delivery end of piston cannula  119  is a trocar suitable for piercing piston end septum  111 . Piston cannula  119  can be made from any suitable material commonly known in the art to be used for piercing, such as hypodermic needles or spikes. Piston cannula  119  also serves to move fluid  129  from fluid chamber  123  to preserved agent ampoule chamber  113 . Thus, it can be considered an integral part of the fluid transport system of the present disclosure. In an embodiment, piston cannula  119  and the interior end of delivery cannula  103  are off-axis of each other, which prevents piston cannula  119  from abutting into delivery cannula  103  in the process of delivering resuspended agent  131 . 
         [0035]    According still to an illustrative embodiment of  FIG. 1 , fluid chamber  123  is defined by dispenser body  101  on the sides, preserved agent ampoule  105  on the delivery end, and piston  115  on the piston end. Both piston  115  and preserved agent ampoule  105  seal fluid chamber from leakage, effectively forcing fluid  129  to move through piston fluid channel  121  when compressive or vacuum force is applied to the chamber. In another embodiment, a sealing membrane can be used to form the delivery end of fluid chamber  123 . The membrane abuts with piston end septum  111  so that piercing the membrane and piston end septum  111  occur in close succession or simultaneously to prevent the loss of fluid  129  in the space between fluid chamber  123  and preserved agent ampoule  105 . 
         [0036]    Referring again to  FIG. 1 , a mixing and dispensing apparatus according to an embodiment of the present disclosure operates as follows. First, a preserved agent  107  is loaded into preserved agent ampoule  105 . In an embodiment, creation of preserved agent  107  can also occur in preserved agent ampoule  105  prior to being sealed by piston end septum  111 . After loading preserved agent  107 , piston end septum  111  is applied to preserved agent ampoule  105 . 
         [0037]    Delivery of resuspended agent  131  by compression force within preserved agent ampoule chamber  113  allows a precise and accurate delivery of a predetermined dosage of resuspended drug  131  to the patient. Moreover, if the factory preloads the system, the entire apparatus can be opened and operated in the presence of the patient, which allays patient concerns about safety and contamination stemming from improper sterile technique or reuse of hypodermic needles. 
         [0038]    In another embodiment, the system is flexible. Dispenser body  101  and piston  115  are reusable after being properly cleaned and sterilized. Additionally, doctors can choose from various available fluids when fluid  129  is loaded on-site. Reuseable core components provide a mixing and dispensing apparatus that is both cost effective and simple to load and operate. Additionally, it also gives doctors greater flexibility in the way preserved agent  107  is mixed, in addition to the concentration of the dose administered. These features make embodiments of the present disclosure superior to other devices on the market today. 
         [0039]    An embodiment of the present disclosure also includes a backflow restrictor built into piston cannula  119  or piston fluid channel  121 , as is commonly known in the art. The backflow restrictor allows fluid  129  to flow unidirectionally from piston fluid channel opening  125  towards piston cannula opening  127 . One such embodiment comprises a one-way valve, as commonly known to artisans. In its closed state, the one-way valve is positioned such that the edges form a tight seal within piston fluid channel  121  or piston cannula  119 . When fluid  129  flows in the proper direction from piston fluid channel opening  125  towards piston cannula opening  127 , the one-way valve is forced into an open position by the flow of the fluid. However, fluid flowing from piston cannula opening  127  to piston fluid channel opening  125  forces the one-way valve to close, which seals piston fluid channel  121  to back flow. 
         [0040]    Consequently, as piston end septum  111  moves through preserved agent ampoule chamber  113  toward delivery end septum  109 , the pressure in preserved agent ampoule chamber  113  increases, which seals piston fluid channel  121  and forces resuspended agent  131  to flow into delivery cannula  103 , rather than back through piston cannula  119  and fluid channel  121  into fluid chamber  123 . 
         [0041]    Another embodiment includes, in addition to that already disclosed, a lever that, when activated, advances preserved agent ampoule  105  into a second position as shown in  FIG. 4 . The lever rests on preserved agent ampoule  105  and contains an activator positioned on the exterior of dispenser body  101 . When activated, the portion of the lever resting on preserved agent ampoule  105  exerts sufficient force push preserved agent ampoule  105  into the second position preparatory to delivery of resuspended agent  131 . 
         [0042]    An embodiment of the present disclosure as illustrated in  FIG. 5  comprises a single-piece piston assembly. As shown in  FIG. 5 , the piston cannula  119  is spike port  135 . At least one opening forms piston fluid channel opening  125 . The end of spike port  135  forms piston cannula opening  127 . The mechanism of delivery of fluid  129  into preserved agent ampoule chamber  113  occurs as previously described. 
         [0043]    Spike ports are well known in the art and easy to manufacture. Spike port  135  can be integrated into piston  115  in a single molding process. Thereafter, at least one opening is created forming piston fluid channel opening  125 , which is created so as to be in fluid communication with piston cannula opening  127 . Thus, piston fluid channel opening  125 , piston fluid channel  121 , and piston cannula opening  127  form a sealed, continuous channel by which fluid chamber  123  is put into fluid communication with preserved agent ampoule chamber  113 . Spike port  135  can be made of materials that are well known in the art. 
         [0044]    In an illustrative embodiment as shown in  FIG. 6 , piston  115  further contains adjustment mechanism  141  connected to fluid adjustment actuator  153  on plunger  117 . Turning fluid adjustment actuator  153  advances or retracts cannula assembly  149 , which comprises at least piston fluid channel  121  and piston cannula  119 . Adjustment of cannula assembly  149  allows for variations in the volume of fluid  129  to be moved into preserved agent ampoule chamber  113 , allowing for the preparation of various concentrations of resuspended agent  131 . 
         [0045]    An illustrative example of similar adjustment mechanism  141  comprises a screw-like mechanism allowing the axial length of cannula assembly  149  to be adjusted. As seen in greater detail in an illustrative example in  FIGS. 7 and 8 , fluid adjustment actuator  153  is turned to actuate the screw-like mechanism that advances or retracts cannula assembly  149 . Specifically, plunger housing  151  houses a threaded fluid adjustment actuator  153 . Fluid adjustment actuator  153  has a delivery end, which has plunger threads  147 . Plunger threads  147  articulate with cannula assembly threads  148  such that when fluid adjustment actuator  153  is turned, cannula assembly advances or retracts axially along the long axis of the present disclosure. 
         [0046]    Cannula assembly  149  contains at least one cannula assembly positioning member  155  to ensure that piston  115  and cannula assembly  149  remain correctly aligned relative to each other. Within the piston, at least one cannula assembly receiver  143  receives cannula assembly positioning member  155  as shown in  FIGS. 7 and 8 . Each cannula assembly receiver  143  receives at least one cannula positioning member  155 . 
         [0047]    In a similar embodiment, the cannula assembly  149  adjustment mechanism comprises a notched positioning mechanism allowing the axial length of cannula assembly  149  to be adjusted. Fluid adjustment actuator  153  is connected to the cannula assembly. The cannula assembly contains a protuberance that articulates with notches in piston  121 . In a first position, the protuberance fits into one of a plurality of notches, fixing the position of the protuberance with respect to the notch. Rotating the cannula assembly  149  moves it into a second position where cannula assembly  149  is not positioned in a notch and may move axially. The plurality of notches allows for a plurality of fixed positions for cannula assembly  149  with respect to piston  115 . Thus, variations in the volume of fluid  129  moved into preserved agent ampoule chamber  113  is accomplished. 
         [0048]    Referring to an illustrative method, preserved agent ampoule  105  is loaded into dispenser body  101  as shown in  FIG. 1  either at the factory or at the site of delivery of the agent. After preserved agent ampoule  105  is loaded, fluid  129  is placed into dispenser body  101 . Thereafter, piston  115  is inserted into dispenser body  101  on the piston end, thereby forming fluid chamber  123  between piston  115 , the dispenser body  101 , and preserved agent ampoule  105 . This combination of steps forms the configuration depicted in  FIG. 1 . The loading of fluid  129  into fluid chamber  123  and insertion of piston  115  into dispenser body  101  are also conducted under sterile conditions. 
         [0049]    According to an embodiment of an illustrative method, sealing of preserved agent ampoule  105  may occur under vacuum conditions sufficient to move fluid  129  from fluid chamber  123  into preserved agent ampoule  105  when piston end septum  111  is pierced. The vacuum pressure should not be so great as to prematurely dislodge piston end septum  111  towards delivery end septum  109 . The process of loading preserved agent  107  into preserved agent ampoule chamber  113  should be conducted under sterile conditions. 
         [0050]      FIG. 2  shows an embodiment of the process of resuspension of preserved agent  107  in fluid  129 , which occurs in preserved agent ampoule  105 . In order to move fluid  129  into preserved agent ampoule  105 , dispenser body  101  is held in an inverted position such that the force of gravity holds fluid  129  against piston  115  and over piston fluid channel opening  125 . Force is applied to piston  115  driving it into dispenser body  101  towards the delivery end. The net result forces piston cannula  119  to pierce piston end septum  111  such that piston cannula opening  127  is placed into preserved agent ampoule chamber  113 , which puts fluid chamber  123  in fluid communication with preserved agent ampoule chamber  113 , as shown in  FIG. 2 . The application of either continued compression force on piston  115  or a vacuum in preserved agent ampoule chamber  113  or a combination of these forces moves fluid  129  from fluid chamber  123  into preserved agent ampoule chamber  113  through piston fluid channel  121 . 
         [0051]    Referring now to an embodiment represented in  FIG. 3 , mixture of fluid  129  with preserved agent  107  in preserved agent ampoule chamber  113  resuspends preserved agent  107 . Resuspended agent  131  is delivered via delivery cannula  103 . In one embodiment, preserved agent ampoule  105  and dispenser body  101  are transparent, allowing the person administering resuspended agent solution to visually confirm that preserved agent  107  is fully admixed with fluid  129  prior to delivery of resuspended agent  131 . This extra step increases the accuracy of the dosage concentration delivered to each patient. 
         [0052]    According still to  FIG. 3 , force applied to piston  115  drives piston  115  to a position where it rests against preserved agent ampoule  105 . Continued pressure on piston  115  moves preserved agent ampoule  105  into a second position preparatory for delivery of resuspended agent  131 . As preserved agent ampoule  105  moves towards its second position, the interior end of delivery cannula  103  pierces delivery end septum  109  of preserved agent ampoule  105  such that delivery cannula  103  is placed into fluid communication with preserved agent ampoule chamber  113  as shown in  FIG. 4 . 
         [0053]    According to an embodiment demonstrated in  FIG. 4 , additional pressure applied to piston  115  drives piston end septum  111  towards delivery end septum  109 . Once the interior end of delivery cannula  103  pierces delivery end septum  109 , preserved agent ampoule  105  ceases to move with continued pressure on piston  115 . However, as additional force is applied to piston  115 , piston end septum  111  moves through preserved agent ampoule chamber  113  towards delivery end septum  109 , which reduces the volume of preserved agent ampoule chamber  113 . Delivery of resuspended agent  131  is thus accomplished by the reduction in volume of preserved agent ampoule chamber  113 . This forces resuspended agent  131  into the interior end of delivery cannula  103 , through delivery cannula  103 , and out the exterior end of delivery cannula  103 , thereby effectuating delivery of resuspended agent  131 . 
         [0054]    An embodiment of a method of delivering a specified volume of fluid  129  into preserved agent ampoule chamber  113  is demonstrated in  FIGS. 7 and 8 . As shown in  FIG. 7 , cannula assembly is in a first position. Turning fluid adjustment actuator  153  advances or retracts cannula assembly  149  as shown in  FIG. 8 . During the adjustment process, the articulation of cannula assembly positioning member  143  and cannula assembly receiver  155  preserve the correct alignment of cannula assembly  149  relative to piston  115 . Gradation marks may be used to allow precise delivery of a specified volume of fluid  129  into preserved agent ampoule chamber  113 . 
         [0055]    While the apparatus and method have been described in terms of what are presently considered to be the most practical and preferred embodiments, it is to be understood that the disclosure need not be limited to the disclosed embodiments. It is intended to cover various modifications and similar arrangements included within the spirit and scope of the claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structures. The present disclosure includes any and all embodiments of the following claims.