Abstract:
The present invention provides a sample cartridge for use with an air and gas sampling device. The cartridge includes a body that defines an interior space, a top portion attached to the body and substantially covering the interior space, and first and second valves seated in the top portion of the cartridge. The valves automatically seal to prevent leakage from the cartridge when the cartridge is not in operable position within the air and gas sampling device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable. 
     INCORPORATION BY REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to chemical and biological sampling, and more specifically to a self-sealing sample cartridge for use with a device for monitoring ambient air or other gas for chemical or biological compounds. 
     Systems for real-time detection of biological and chemical compounds or agents are known in the art. Exemplary known systems may utilize a contactor having a substrate therein, such that the air or gas being analyzed comes into contact with the substrate, such as water, so that chemical and biological compounds or agents are transferred thereto. 
     Such devices may have a number of limitations. For example, known devices may utilize a sample container that is not removable from the device but is, instead, an integral component thereof. This makes cleaning of the sample container difficult. Further, even if the sample container is removable, it may be a permanent part of the device, being used over multiple sampling runs throughout the life of the device. This increases the chances that the sample container will suffer from cross-contamination between runs, from being generally dirty, or from ordinary wear and tear to the device during use. Further, such sample containers may become prone to leakage due to weakening seals or other portions of the container structure with reuse over time. It is therefore desirable to provide a self-sealing, single-use sample cartridge for use with a gas or air monitoring device, such that the cartridge is not susceptible to cross-contamination or dirtying due to repeated use, and is not susceptible to structural weakening due to repeated use over time. 
     A further problem with some known air and gas monitoring devices is that, upon initial use, the device must provide fluid from a fluid reservoir into the device so that the fluid can be delivered to a contactor, where it acts as a substrate during the sampling run. The process of delivering fluid from a reservoir, through the device, to a contactor takes time and can lead to slow startup times for the sampling device. Thus, it is desirable to provide a component to such a device that allows for rapid startup of the device. Further, in some known devices, the use of a pressure-based fluid level control would require a component that maintains a pressure seal at its machine interface. 
     Further, in known devices, collection and storage of a sample after a sampling run may require transfer of the sample to a storage container external to the device, such as by manual transfer at the hands of a technician or other skilled worker. This allows opportunity for contamination of the sample during transfer, or due to contamination of the storage receptacle. It also presents the possibility of exposure of the technician to harmful chemicals or agents within the sample. 
     An additional problem presented by devices that require transfer of the collected sample to a storage container is that the storage container may be mislabeled or may contain insufficient data to identify the sample and the parameters of the sampling run from which the sample was obtained. This can lead to faulty interpretation of data taken from analysis of the sample, or in some cases may render the sample useless for further analysis. Thus, it is desirable to provide a sample storage container for any given sample within the sampling device itself, and likewise to provide a unique identifier for any given sample. Likewise, it is further desirable to provide an automatic means of imparting identification information to the sample storage container upon delivery of the sample to the container. 
     Further, in known devices it is typically required that the collected sample be pretreated with buffer solutions, bio-chemical assays, or other chemicals that are used as part of the analysis method. Thus it is desirable to provide a sample storage container that is pre-filled with the required chemicals for analysis. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a sample cartridge for use with an air and gas sampling device. The cartridge includes a body that defines an interior space, a top portion attached to the body and substantially covering the interior space, and a plurality of valves seated in the top portion of the cartridge. The present invention preferably uses three or four valves. The valves automatically seal to prevent leakage from the cartridge when the cartridge is not in operable position within the air and gas sampling device. It is preferred that the valves deform when the present cartridge is installed in an air and gas sampling device, thereby allowing unrestricted fluid flow in and out of the cartridge. 
     In another aspect of the present invention, a lid portion is provided, the lid being engageable with the top portion of the cartridge. When the lid is closed, it forms a seal against the valves. The lid portion may be fixedly attached to the body portion, such as by a hinge, or may be entirely removable from the body. 
     In another aspect of the invention, gripping features are provided to allow the user to insert and remove the cartridge from the air sampling device. 
     In another aspect of the present invention, the sample cartridge is provided with a data storage portion for storing data related to the cartridge or to the sample stored within the cartridge. The data storage portion may be a magnetic storage device, a flash storage device, a computer-readable disc, a RAM storage device, a radio frequency identification device (RFID), a combination of these, or any other suitable data storage device, and may be interfaced with remotely or by direct connection to the present invention. 
     In yet another aspect of the present invention, the sample cartridge is provided with a data receiver for receiving data transmitted from the air and gas sampling device or from some other source external to the sample cartridge. 
     In another aspect of the invention, the sample cartridge is provided with buffers, biochemical markers, or other chemicals that aid in analysis of the sample. 
     In still another aspect of the present invention, the sample cartridge is provided with a data transmitter for transmitting data to the air and gas sampling device or to some other external receiver. 
     In another aspect of the present invention, the sample cartridge is a single-use, disposable cartridge. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-section of a perspective view of a sample cartridge according to the present invention, the sample cartridge having a cap portion in the open position. 
         FIG. 2  is a cross-section of a perspective view of a sample cartridge according to the present invention, the sample cartridge having a cap portion in the closed position. 
         FIG. 3  is a cross-section view of a portion of an exemplary air and gas sampling device having a sample cartridge according to the present invention placed in operable position therein. 
         FIG. 4  is a cross-section of a perspective view of an exemplary air and gas sampling device adapted for use with a sampling cartridge according to the present invention. 
         FIG. 5  is a perspective view of one embodiment of a sample cartridge constructed in accordance with the teachings of the present invention. 
         FIG. 6  is a cross-sectional view of one embodiment of a sample cartridge constructed in accordance with the teachings of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     According to the principles of the present invention, a self-sealing sample cartridge is provided for use with an air and gas sampling device. The cartridge is used to provide an initial fluid charge to a contactor of the air and gas sampling device, as well as to accept and provide additional fluid during a sampling run and to serve as a final sample storage container after the completion of a sampling run. The cartridge also serves as an air pressure bridge during operation, and a vacuum reservoir during sample extraction. In one aspect of the present invention, the sample cartridge is a single-use cartridge. 
     Turning now to the drawings, wherein like numerals represent like parts, the numeral  10  refers generally to a sample cartridge constructed in accordance with the teachings of the present invention. Sample cartridge  10  includes a body  12 , a top portion  14 , a cap  16 , and first, second and third valves  18   a ,  18   b , and  18   c.  A position for a fourth valve  18   d , described below, is preferably also provided, but is sealed in the embodiment of the present invention shown in the drawings. These and other features of sample cartridge  10  are described more fully below. 
     Sample cartridge  10  has multiple functions when used in conjunction with a device or system for monitoring the ambient air or other gases. When first installed for use in a gas and air sampling device, sample cartridge  10  preferably contains a volume of fluid that acts as the initial collection fluid charge. This initial fluid charge is delivered to a contactor of the air and gas sampling device when a collection cycle is commenced. The sample cartridge also acts as a fluid level maintenance reservoir during a collection run, when the air and gas monitoring device is collecting particles from samples of the air or other gas being monitored. Thus, fluid contained within sample cartridge  10  is delivered to the contactor of the air and gas sampling device over the course of the sampling run. Fluid from an external source may be added to the cartridge during a run, and air pressure may be introduced to the cartridge to affect the rate and direction of fluid transfer to or from the cartridge. Finally, sample cartridge  10  also acts as the final sample collection vessel at the end of a collection run. When the collection run is ended, air pressure in the cartridge is reduced to transfer fluid from the contactor of the air and gas sampling device to the sample cartridge  10  for storage or further processing. The fourth valve position  18   d  allows fluid in the cartridge to be drawn out while the cartridge is mounted in the air and gas sampling device, for use by internal analysis or archival devices. Further, the fourth valve position allows for the cartridge to be used for multiple samples while preserving the ability to replace the cartridge quickly and easily. 
     As shown in  FIG. 1 , body  12  and top portion  14  are preferably welded together or otherwise hermetically sealed. Alternatively, sample cartridge  10  may be produced such that body  12  and top portion  14  are constructed from a single, integral piece of material. Any manner of check valve may be used that restricts flow in one direction and can be mechanically opened to allow for flow in two directions. First, second, and third valves  18   a ,  18   b , and  18   c  are pressed into top portion  14 , and each preferably includes a duck-bill type seal  15  that remains closed until sample cartridge  10  is inserted into the ambient air and gas monitoring device with which it is being used. First, second, and third valves  18   a ,  18   b , and  18   c  are preferably opened upon insertion into the air and gas monitoring device by a structure within the device itself that holds valves  18   a ,  18   b , and  18   c  in open positions. For example, the air and gas monitoring device may include pins on a manifold (an example of which is described more fully below) that serve to open valves  18   a ,  18   b , and  18   c  when sample cartridge  10  is placed in operating position prior to use of the sampling device. Once sample cartridge  10  is removed from the sampling device, valves  18   a ,  18   b , and  18   c  close, for example, by the action of molded ribs  20 , which serve to force the closure of the valves. Once valves  18   a ,  18   b  and  18   c  are closed, a seal is created such that collection fluid is prevented from leaking out of sample cartridge  10 , thereby preventing the exposure of the user to contaminated fluid, and other fluids are prevented from entering sample cartridge  10  and contaminating the fluid therein. 
     Cap  16  is preferably molded as part of top portion  14 , connected to top  14  by a molded hinge  22 . When cap  16  is closed, cap  16  is held in place by detents  24 , which interface with slots  26  to allow cap  16  to snap into place. This method of securely closing cap  16  allows for repeated opening and closing of cap  16  without loss of performance over time, and also allows for secure shipping and other handling of sample cartridge  10  without leakage of fluid therein or damage to valves  18   a ,  18   b , and  18   c.  Cap  16  is sealed to top portion  14  of sample cartridge  10  by interference between sealing bosses  28  in cap  16  and the receiving geometry of valves  18   a ,  18   b , and  18   c.  Although as shown in the figures, cap  16  is molded as an integral part of top portion  14 , it is contemplated that cap  16  and top portion  14  may be provided as two separate portions. 
       FIG. 2  depicts a cross-sectional view of a sample cartridge  10  constructed in accordance with the teachings of the present invention, sample cartridge  10  being shown with cap  16  in a closed position. With cap  16  in a closed position, sealing bosses  28  mate with the receiving geometry of valves  18   a ,  18   b , and  18   c  to seal sample cartridge  10 , such that fluid does not leak from sample cartridge  10  and fluid contained within sample cartridge  10  is not contaminated by particles or fluid from sources external to sample cartridge  10 . With cap  16  in a closed position, sample cartridge  10  may be shipped or otherwise transported or handled without loss of fluid from within sample cartridge  10 , and without risk to the user due to contact with the contents thereof. Further, the outer surface of cap  16  may be textured to better accept identification markings applied by the user with pen or other suitable means. 
     While sample cartridge  10  may be constructed as described above, with first, second, and third valves  18   a ,  18   b , and  18   c , sample cartridge  10  may also be provided as shown in  FIGS. 1 and 2  with a fourth valve as indicated above. Alternatively, sample cartridge  10  may be provided with only two valves  18   a  and  18   b.  In such an embodiment of the present invention, one of valves  18   a  or  18   b  serves to allow fluid to flow along a sample line, while the other of valves  18   a  or  18   b  serves as a pressure connector between the cartridge and a contactor of a gas and air sampling device. One of valves  18   a  or  18   b  may further include the capacity to inject water into the system. 
       FIG. 3  depicts sample cartridge  10  as installed in an air and gas sampling device. Manifold  30  of the air and gas sampling device shown in the figures includes pins  32  that interface with first, second, and third valves  18   a ,  18   b , and  18   c , holding them open. The receiving geometry of first, second, and third valves  18   a ,  18   b , and  18   c  is preferably such that a seal is formed between valves  18  and pins  32 . Once first and second valves  18  are opened by pins  32 , valves  18   a ,  18   b , and  18   c  are in bidirectional liquid communication with manifold  30 , and thus in communication with the air and gas sampling device. 
     As shown in  FIG. 3 , sample cartridge  10  is oriented in a vertical position when used in the exemplary air and gas monitoring device depicted in the drawings. When used in other such devices, sample cartridge  10  may have other orientations, including a horizontal orientation. Likewise, the size, shape, and overall configuration of sample cartridge  10  may differ from that shown in the drawings when sample cartridge  10  is used with other than the exemplary air and gas sampling device shown in the drawings. Further, the placement and configuration of valves  18  may vary. So long as the basic functionality of sample cartridge  10 , as described herein, is preserved, the physical shape and configuration may be altered to meet the requirements of a specific sampling device or sampling application. 
     When sample cartridge  10  is first inserted into an air and gas sampling device, the sample cartridge preferably contains enough fluid to initially charge a contactor  42  (best seen in  FIG. 4 ) of the air and gas sampling device. An air space encompasses two upper manifold pins  32  (one of which is visible in  FIG. 3 , the other, not visible, being positioned adjacent the first). One of upper manifold pins  32  is preferably in fluid communication with an air space within contactor  42  of the air and gas sampling device, a pump (not shown) that can draw a vacuum on the cartridge or can extract excess fluid from the cartridge, as well as with valve  18   c  of sample cartridge  10 . The other upper manifold pin  32  is in fluid communication, via manifold  30 , with a pump (not shown) that can charge sample cartridge  10  with a gas or liquid, as well as with valve  18   a  of sample cartridge  10 . Lower manifold pin  32  is in fluid communication with the bottom of contactor  42  of the air and gas sampling device, as well as with valve  18   b  of sample cartridge  10 . When a collection cycle is initiated, the pump in communication with one of upper manifold pins  32  pressurizes the cartridge, which pushes fluid through lower manifold pin  32  and into contactor  42  of the sampling device. This allows for a rapid startup of the device. 
       FIG. 4  is a cross-sectional view of an exemplary air and gas sampling device  34  for which the sample cartridge  10  shown in  FIGS. 1-3  is adapted to be used. Manifold  30  is shown in the figure, as are manifold pins  32 . Device  34  includes a bay  36  adapted to receive sample cartridge  10 . In order to place sample cartridge  10  in operational position within device  34 , sample cartridge  10  is inserted such that valves  18  of sample cartridge  10  line up with manifold pins  32  of device  34 . Once sample cartridge  10  is in place, device  34  is ready for use. In some embodiments of the present invention, a protective door may be provided over bay  36  such that internal components of device  34  are protected when sample cartridge  10  is not in place. 
     As can be seen in  FIG. 4 , sample cartridge  10 , once in position, is in communication with a contactor  42  of device  34  by way of manifold  30  and manifold pins  32 , which communicate with valves  18   a ,  18   b , and  18   c  of sample cartridge  10 . For example, line  40  provides fluid communication between a lower manifold pin  32  and a fluid inlet  46  of contactor  42 . Likewise, line  44  provides fluid communication between an upper manifold pin  32  and an opening  48  positioned above a fluid level in contactor  42 . A second upper manifold pin (not shown) may provide fluid communication with either an internal pump (not shown) of device  34 , or an external pump adapted to be used with device  34 . 
     In aspects of the present invention having a valve  18   c , wherein an upper manifold pin  32  is in fluid communication with a contactor of the air and gas sampling device, the communication between upper manifold pin  32  (and therefore an upper air space within sample cartridge  10 ) and contactor  42  of the air and gas sampling device combines with the pressure caused by the fluid in the contactor to create a pressure balance that allows fluid to gradually flow out of sample cartridge  10  and into the contactor to replace fluid that evaporates from the contactor. In such an aspect of the present invention, a sensor may also be provided to monitor the fluid level in sample cartridge  10  such that additional fluid may be pumped into sample cartridge  10  via a pump in communication with an upper manifold pin  32 , either from a fluid reservoir included in the air and gas sampling device or from some source external to the air and gas sampling device. Thus, sample cartridge  10  can be provided with a continuous source of fluid, enabling long-term, continuous operation of the sampling device. 
     In addition to the aspects of the present invention described above, sample cartridge  10  may be provided with an integral memory device that can receive and record data, such as the lot number of a particular cartridge, the date of manufacture thereof, collection date of the sample, run time, flow rates, collection fluid type, ambient temperature, humidity, occurrence of system alarms, and the like. Such a memory device could include a magnetic storage device, a flash storage device, a RAM storage device, a computer-readable disc storage device, other devices, or any combination of the foregoing, and may be molded into the structure of sample cartridge  10  or otherwise affixed thereto. A transmission or receiving portion may be included into the air and gas sampling device such that the device may communicate information to sample cartridge  10 , or may receive information therefrom. Such transmission or receiving of communications may occur via, for example, radio frequency, or by any other suitable methods of transmitting or receiving data. In addition to a data storage device, an identifier may be included with the present sample cartridge, the identifier simply providing identifying information that may subsequently be associated with specific data regarding a sample contained within the sample cartridge. The identifier may be a human-readable identifier, such as, for example, a serial number printed on the cartridge, or may be a computer-readable identifier such as, for example, a bar code or RFID device. 
       FIGS. 5 and 6  illustrate additional features that may be included with some embodiments of sample cartridge  10 .  FIG. 5  is a perspective view of one embodiment of a sample cartridge constructed in accordance with the teachings of the present invention, illustrating gauge marks  48  that may be molded into the surface of sample cartridge  10 , allowing for a quick and easy estimate of the sample volume therein. Any suitable markings may be used to allow for estimation of the volume of a sample or other fluid within sample cartridge  10 . 
       FIG. 6  provides a cross-sectional view of sample cartridge  10 , and shows molded ribs  47 , which allow for a user&#39;s fingers to securely grip sample cartridge  10  when using gloves or other hand-protective gear, and also allows for easy insertion of sample cartridge  10  into an air and gas sampling device, as well as easy removal therefrom. Any suitable gripping portion may be used to allow easy manipulation of cartridge  10 . 
     Each of the various components of sample cartridge  10  may be constructed from a variety of materials, as will be readily apparent to those of skill in the art upon reading this disclosure. Materials may be selected, for example, according to weight, durability, insulating qualities, and the like. In addition, materials may be selected according to chemical compatibility with chemicals or agents likely to come into contact with sample cartridge  10  during use. 
     The specific embodiments of the present invention described above are provided by way of example only, and are not meant to limit the subject matter of the present invention. Various alterations and modifications to the above will be apparent to those of skill in the art upon reading this disclosure. For example, the number, configuration, arrangement, and type of valves may be varied without departing from the spirit or scope of the present invention. Likewise, the size, shape, and configuration of sample cartridge  10 , as well as the mechanism by which sample cartridge  10  associates with a gas and air sampling device, may be varied. The present invention is limited only by the claims that follow.