Patent Publication Number: US-9901928-B2

Title: Calibration fluid cartridge for an in vitro medical diagnostic device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present Application claims the benefit of and priority to U.S. Provisional Patent Application No. 61/567,585 titled “Diagnostic Device” and filed on Dec. 6, 2011, the complete disclosure of which is incorporated herein by reference. The present Application also claims the benefit of and priority to U.S. Provisional Patent Application No. 61/725,476, filed Nov. 12, 2012, the entirety of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     Electrochemical diagnostic devices are analytical tools combining a chemical or biochemical recognition component (e.g., an enzyme or antibody) with a physical transducer such as a platinum electrode. The chemical or biochemical recognition component can be used to selectively interact with an analyte of interest and generate an electrical signal through the transducer. The selectivity of certain biochemical recognition components makes it possible to develop electrochemical sensors which can accurately detect certain biological analytes in blood. 
     In vitro diagnostic testing has traditionally been performed at large, well-equipped testing centers. These conventional testing centers offer efficient and accurate testing of a high volume of fluid samples, but are not able to offer immediate results. A medical practitioner must collect fluid samples, the samples must be transported to a laboratory, then processed by the laboratory, and finally the results are communicated to the patient. Conventional in vitro diagnostic testing does not offer immediate results. 
     Also, conventional in vitro diagnostic testing requires trained laboratory technicians to perform the testing in order to ensure the accuracy and reliability of the test. User errors by the person handling the sample can result in contamination of surfaces, spilled specimens, or damage to the diagnostic device resulting in extensive repair and maintenance costs. Conventional in vitro diagnostic testing requires a skilled technician to perform multiple stages of the testing process, and is still subject to user error. 
     SUMMARY 
     An embodiment of the present disclosure relates to a diagnostic system. The diagnostic system includes a removable assay cartridge comprising fluid paths and a plurality of electrochemical sensors, a removable calibration fluid cartridge, and a diagnostic device having a housing and processing electronics for conducting the diagnostics within the housing. The housing further includes a first opening for receiving at least a portion of the removable assay cartridge and a second opening for receiving at least a portion of the removable calibration fluid cartridge. The processing electronics of the diagnostic device receive signals from the electrochemical sensors and the removable assay cartridge and the removable calibration fluid cartridge engage for the communication of fluid so that there is no fluid communication from the removable assay cartridge to any surface of the diagnostic device and no fluid communication from the removable calibration fluid cartridge to any surface of the diagnostic device. 
     In this embodiment, the diagnostic system may include one or more valve control mechanisms. The valve control mechanism includes a cam plate configured to rotate, the cam plate under control of the processing electronics and having one or more concentric grooves comprising one or more raised portions. The valve control mechanism also includes one or more valve actuators having one or more guides, the guides configured to align with the concentric grooves, maintaining contact with the grooves as the cam plate rotates. The valve actuators are configured to actuate one or more valves when the guides encounter the raised portion of the cam plate, and the valves are configured to control at least the flow of fluid in the removable assay cartridge. 
     Another embodiment of the present disclosure relates to a diagnostic device. The diagnostic device includes a housing having an assay port for receiving a removable assay cartridge, a circuit receiving data from at least one electrochemical sensor on the removable assay cartridge when the removable assay cartridge is fully installed in the assay port, processing electronics configured to receive the data from the circuit and to conduct diagnostics using the received data, and a valve control mechanism under control of the processing electronics and configured to control the flow of fluid in the removable assay cartridge without touching the fluid in the removable assay cartridge. 
     In this embodiment, the valve control mechanism may include a cam plate configured to rotate, the cam plate under control of the processing electronics and having one or more concentric grooves comprising one or more raised portions. The valve control mechanism may also include one or more valve actuators having one or more guides, the guides configured to align with the concentric grooves, maintaining contact with the grooves as the cam plate rotates. The valve actuators may be configured to actuate one or more valves when the guides encounter the raised portion of the cam plate, and the valves may be configured to control at least the flow of fluid in the removable assay cartridge. 
     Another embodiment of the present disclosure relates to a valve control mechanism for a diagnostic device configured to receive a removable assay cartridge. The valve control mechanism includes an engagement device having a cycle with one or more predetermined points, the engagement device configured to engage one or more valve actuators at one or more predetermined points of the cycle, one or more valve actuators configured to actuate one or more valves when the valve actuators are engaged by the engagement device. The valves are configured to control at least the flow of fluid in the removable assay cartridge. 
     Another embodiment of the present disclosure relates to a calibration fluid cartridge for a diagnostic device. The calibration fluid cartridge includes a chamber for holding unused calibration fluid, a flow channel configured to receive calibration fluid from the chamber and to provide calibration fluid to an output, and a pinch valve configured to control the flow of the calibration fluid through the fluid channel. In this embodiment, the calibration fluid cartridge does not carry a mechanism controlling actuation of the pinch valve. 
     Another embodiment of the present disclosure relates to a calibration fluid cartridge for a diagnostic device. The calibration fluid cartridge includes a chamber for holding unused calibration fluid, a flow channel configured to receive calibration fluid from the chamber and to provide calibration fluid to an output, a junction for receiving gas in the flow channel, and a system of valves such that gas and calibration fluid can controllably flow to the output. 
     Another embodiment of the present disclosure relates to a disposable assay cartridge including a housing having at least a top end and a bottom end. The top end includes an inlet, including an interface for accepting a receptacle containing a sample fluid. The disposable assay cartridge further includes a sample fluid channel in fluid communication with the inlet for receiving sample fluid, the sample fluid channel being interrupted by a valve that controls a flow of sample fluid into an interior fluid channel that is in fluid communication with (i) a calibration fluid channel, (ii) an array comprising a plurality of electrochemical sensors, and (iii) a waste area downstream of the array comprising a plurality of electrochemical sensors for accepting spent fluids, including used calibration fluid. In this embodiment, the bottom end includes a second inlet for introducing calibration fluid or air into the calibration fluid channel and an outlet for communication with pressure or vacuum pump for aspiration of calibration fluid, air, or sample fluid. 
     Another embodiment of the present disclosure relates to a valve control mechanism for a diagnostic device configured to receive a removable assay cartridge. The valve control mechanism includes a cam plate configured to rotate, the cam plate having one or more concentric grooves comprising one or more raised portions, one or more valve actuators having one or more guides, the guides configured to align with the concentric grooves, maintaining contact with the grooves as the cam plate rotates. The valve actuators are configured to actuate one or more valves when the guides encounter the raised portion of the cam plate, and the valves are configured to control at least the flow of fluid in the removable assay cartridge. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The disclosure will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements, in which: 
         FIG. 1  is a perspective view of an in vitro medical diagnostic device and attached assay cartridge, according to an exemplary embodiment. 
         FIG. 2  is a perspective view of the in vitro medical diagnostic device of  FIG. 1 . 
         FIG. 3  is a side view of the in vitro medical diagnostic device of  FIG. 1 . 
         FIG. 4  is another side view of the in vitro medical diagnostic device of  FIG. 1 . 
         FIG. 5  is another side view of the in vitro medical diagnostic device of  FIG. 1 , this view illustrating an open door  14  and the placement of a calibration cartridge  30  within the medical diagnostic device, according to an exemplary embodiment. 
         FIG. 6  is a back view of the in vitro medical diagnostic device of  FIG. 1 . 
         FIG. 7  is a perspective view of an assay cartridge for insertion into the medical diagnostic device, according to an exemplary embodiment. 
         FIG. 8  is a front view of the assay cartridge of  FIG. 7 . 
         FIG. 9  is a back view of the assay cartridge of  FIG. 7 . 
         FIG. 10A  is a schematic view of a system provided by the diagnostic device, including a calibration cartridge, an assay cartridge, a fluid path, and a pump, according to an exemplary embodiment. 
         FIG. 10B  is a close up view of a point on the fluid path of the assay cartridge where the calibration fluid channel and the fluid sample channel meet, according to an exemplary embodiment. 
         FIG. 10C  is a close up view of the fluid path connection between the assay cartridge and the calibration cartridge, according to an exemplary embodiment. 
         FIG. 11A  is a schematic view of a calibration cartridge connected to an assay cartridge to form a fluid path for the flow of fluid actuated by a pump, according to an alternative embodiment. 
         FIG. 11B  is a close up view of the point on the fluid path of the assay cartridge where the calibration fluid channel and the fluid sample channel meet, according to an alternative embodiment. 
         FIG. 11C  is a close up view of the fluid path connection between the assay cartridge and the calibration cartridge, according to an alternative embodiment. 
         FIG. 12  is a simplified back view of the assay cartridge of  FIG. 7 . 
         FIG. 13  is a linear representation of the fluid flow path through the assay cartridge of  FIG. 7 . 
         FIG. 14  is a cross-sectional illustration of the fluid flow across an electronic fluid sensor of the assay cartridge of  FIG. 7 , according to an exemplary embodiment. 
         FIG. 15  is a back view of an assay cartridge, according to an alternative embodiment. 
         FIG. 16  is a back view of the assay cartridge of  FIG. 15  with fluid filling the cartridge, according to an alternative embodiment. 
         FIG. 17  is a linear representation of the fluid flow path through the assay cartridge of  FIG. 15 . 
         FIG. 18  is a cross-section view of a universal syringe interface, illustrating three different sized syringes, on an assay cartridge, according to an exemplary embodiment. 
         FIG. 19  is a front view of an assay cartridge with a syringe loaded from the top, according to an alternative embodiment. 
         FIG. 20  is a front view of the assay cartridge of  FIG. 19 . 
         FIG. 21  is a back view of the assay cartridge of  FIG. 1  with a capillary tube and capillary tube adapter coupled to the assay cartridge, according to an exemplary embodiment. 
         FIG. 22  is a back view of the assay cartridge of  FIG. 15  with a capillary tube and capillary tube adapter coupled to the assay cartridge. 
         FIG. 23  is a perspective view of an assay cartridge, including a valve actuator actuating a pinch valve on the assay cartridge, according to an exemplary embodiment. 
         FIG. 24  is a cross-sectional side view of the assay cartridge of  FIG. 23 , including a valve actuator actuating a pinch valve on the assay cartridge, according to an exemplary embodiment. 
         FIG. 25  is a cross-sectional illustration of a pinch valve in the closed and open position, according to an exemplary embodiment. 
         FIG. 26  is a perspective view and a cross-sectional side view of a pinch valve actuator actuating a pinch valve on an assay cartridge, according to an alternative embodiment. 
         FIG. 27  is a cross-sectional illustration of a pinch valve in the closed and open position, according to an alternative embodiment. 
         FIG. 28  is a perspective semi-transparent view of a calibration cartridge, according to an exemplary embodiment. 
         FIG. 29  is a cross-sectional side view of the calibration cartridge of  FIG. 28 , including a fluid pack, according to an exemplary embodiment. 
         FIG. 30  is a close up cross-sectional view of a rod valve of the calibration cartridge of  FIG. 28 , including the rod valve in the open and closed position, according to an exemplary embodiment. 
         FIG. 31  is a cross-sectional illustration of the calibration cartridge of  FIG. 28 , including a T connector, and a fluid path and an air path from the calibration cartridge, according to an exemplary embodiment. 
         FIG. 32  is a perspective view of a calibration cartridge and two pinch valve actuators, according to an exemplary embodiment. 
         FIG. 33  is a cross-sectional side view of the calibration cartridge of  FIG. 32 , including a fluid pack, according to an exemplary embodiment. 
         FIG. 34  is a cross-sectional view of a calibration cartridge pinch valve in the open and closed positions, according to an exemplary embodiment. 
         FIG. 35  is a perspective and semi-transparent view of a calibration cartridge, according to an alternative embodiment. 
         FIG. 36  is a cross-sectional view of the calibration cartridge of  FIG. 35 , including a fluid pack and a T connector, according to an alternative embodiment. 
         FIG. 37  is a perspective view of the calibration cartridge of  FIG. 35  and a cross-sectional view of the calibration cartridge showing a rod valve in the closed position. 
         FIG. 38  is another perspective view of the calibration cartridge of  FIG. 35  and a cross-sectional view of the calibration cartridge showing a rod valve in the open position. 
         FIG. 39  is another perspective view of the calibration cartridge of  FIG. 35 , showing pinch valve actuators engaging the pinch valves of the calibration cartridge to regulate fluid and/or gas flow, according to an exemplary embodiment. 
         FIG. 40  is a cross-sectional view of the calibration cartridge of  FIG. 39  including pinch valve actuators engaging the pinch valves of the calibration cartridge. 
         FIG. 41  is a close up cross-sectional view of a calibration cartridge pinch valve in the open and closed position, according to an exemplary embodiment. 
         FIG. 42  is a close up cross-section view of a fluid pathway for a calibration cartridge, including a thin film formed over two rubber spacers, according to an exemplary embodiment. 
         FIG. 43  is a close up cross-section view of the fluid pathway of  FIG. 42 , including the T connector. 
         FIG. 44  is a diagram of a hardware organization for an in vitro medical diagnostic device, according to an exemplary embodiment. 
         FIG. 45  is a diagram of a software organization for an in vitro medical diagnostic device, according to an exemplary embodiment. 
         FIG. 46  is a perspective view of a motor assembly for controlling pinch valve actuators and heating elements for a diagnostic device, according to an exemplary embodiment. 
         FIG. 47  is a side view of a motor assembly for controlling pinch valve actuators for a diagnostic device, according to an exemplary embodiment. 
         FIG. 48  is another perspective view of a motor for controlling pinch valve actuators for a diagnostic device, with the pinch valve actuator for an assay cartridge isolated in the illustration, according to an exemplary embodiment. 
         FIG. 49  is another perspective view of a motor for controlling pinch valve actuators for a diagnostic device, with the pinch valve actuators for a calibration cartridge isolated in the illustration, according to an exemplary embodiment. 
         FIG. 50  is an isolated perspective view of a motor for actuating a pinch valve, including a pop up spring for ejecting the assay cartridge, and a locking rod for locking the assay cartridge within the diagnostic device, according to an exemplary embodiment. 
         FIG. 51  is another perspective view of a motor for controlling pinch valve actuators for a diagnostic device, including the assay cartridge, calibration cartridge, syringe, and a portion of the diagnostic device, according to an exemplary embodiment. 
         FIG. 52  is a perspective view of the motor embodiment of  FIG. 47 . 
         FIG. 53A  is a side view of an L-shaped connector for providing calibration fluid from the fluid pack to the calibration cartridge, according to an exemplary embodiment. 
         FIG. 53B  is a back view of the L-shaped connector of  FIG. 53A . 
         FIG. 53C  is a front view of the L-shaped connector of  FIG. 53A . 
     
    
    
     DETAILED DESCRIPTION 
     Before turning to the figures, which illustrate the exemplary embodiments in detail, it should be understood that the present application is not limited to the details or methodology set forth in the description or illustrated in the figures. It should also be understood that the terminology is for the purpose of description only and should not be regarded as limiting. 
     The present disclosure relates to an in vitro medical diagnostic device  10  that includes a removable and saleable solution reservoir, or calibration cartridge  30 . The device also includes a removable assay cartridge  20 . In an exemplary embodiment, the removable assay cartridge  20  includes a polymer body with channels  32  for fluid movement, a valving system for changing or sealing fluid paths, a receiving port  34  for receiving fluid samples  39 , and a plurality of sensors  57 . The diagnostic device  10  can interpret the inputs from the sensors  57 , conduct diagnostics using the inputs from the sensors  57 , and output information (e.g., via display, via printed report, etc.). 
     Referring to  FIGS. 1-6 , an in vitro medical diagnostic device of the present disclosure is shown, according to an exemplary embodiment.  FIG. 1  is a perspective view of the in vitro medical diagnostic device  10  shown with the removable assay cartridge  20  fully inserted into the device  10 .  FIG. 2  is a perspective view of the in vitro medical diagnostic device  10 .  FIG. 3  is a side view of the in vitro medical diagnostic device  10 .  FIG. 4  is another side view of the in vitro medical diagnostic device  10 .  FIG. 5  is another side view of the in vitro medical diagnostic device  10  of  FIG. 1 , this view illustrating an open door  14  and the placement of a calibration cartridge  30  within the medical diagnostic device, according to an exemplary embodiment.  FIG. 6  is a back view of the in vitro medical diagnostic device  10 . 
     The in vitro medical diagnostic device  10  has a housing  27  that provides a shell for the device  10 . The housing  27  may be plastic or any other material suitable for the application. The in vitro diagnostic device  10  is configured to receive an assay cartridge  20  (shown further in  FIGS. 7-9 ). The assay cartridge  20  is inserted into a testing slot  22 . In the illustrated embodiment of  FIG. 1 , a syringe  25  holding a fluid sample  39  (i.e. biological sample, drug sample, etc.) is used to dispense the fluid sample  39  into the cartridge  20 . The device  10  is configured to test the fluid sample  39 , and to report the results to a user via an output. In the illustrated embodiment of  FIG. 1 , the device  10  is shown to include a display screen  18  for providing the output. However, in this or other embodiments, the results may also or alternatively be reported to the user by other outputs, including audio outputs, data communication outputs, or a printout. 
     In exemplary embodiments, the assay cartridge  20  may be removed from the device  10  once the fluid sample  39  is tested. The device  10  may include an eject button  16 , which the user may press to eject the cartridge  20  from the testing slot  22  once the testing has completed. The device  10  may also be configured to eject the cartridge  20  automatically when the testing cycle has completed. In exemplary embodiments, the assay cartridge  20  is disposable (i.e. the cartridge  20  can be removed and replaced). The assay cartridge  20  may be single-use (i.e. used once and replaced with another cartridge  20 ) in some exemplary embodiments. In other exemplary embodiments, the cartridge  20  may be re-cycled and used to test more than one fluid sample  39 . The diagnostic device  10  is intended to be portable, having a handle  26  for carrying the portable device  10  and being sized to fit on a tabletop. 
     In exemplary embodiments, the diagnostic results are reported on a display screen  18 . Processing electronics of the device  10  can cause the display  18  to display information relevant to the particular application. The display screen  18  may be a one-way screen configured to display output to a user, or may be a touch screen configured to receive and respond to user touch input. In exemplary embodiments, the diagnostic device also includes a printer slot  12  configured to receive a paper output by a printer housed within the device  10 . 
     The diagnostic device  10  may also include one or more heating elements  116  (e.g. as shown in  FIG. 47 ). In exemplary embodiments, the heating elements  116  are one or more heating plates located within the testing slot  22  of the device  10 . In the illustrated embodiment of  FIGS. 1-6 , two heating elements  116  are configured such that there is a heating element  116  located on each side of the assay cartridge  20  when the assay cartridge  20  is inserted into the device  10 . The heating elements  116  are caused to control the heat of the fluid (e.g. fluid sample  39 , calibration fluid, etc.) within a testing portion  42  of the assay cartridge  20 , causing the fluid to maintain a substantially constant temperature. In exemplary embodiments, the heating elements  116  are controlled to hold the fluid at a substantially constant temperature of approximately 37 degrees Celsius (approximately 98.6 degrees Fahrenheit). The testing portion  42  may include a plurality of apertures (i.e. fluid reservoirs) positioned along one or more of the planar heating elements  116  (i.e. heating plates). The apertures are configured to hold the fluid within the testing portion  42 , so that the heating elements  116  can control the temperature of the fluid. 
     According to the illustrated embodiment of  FIG. 1-6 , the in vitro medical diagnostic device  10  also includes a calibration cartridge door  14 . The calibration cartridge door  14  is shown to open away from the device  10 . The calibration cartridge door  14  and the opening behind the door  14  are sized to receive a disposable calibration cartridge  30  (shown in further detail in  FIGS. 28-43 ). The calibration cartridge door  14  is opened by a door latch  13  in the illustrated embodiments, but may be opened by other mechanisms in other exemplary embodiments. The door latch  13  is located adjacent to the door  14 . Behind the calibration cartridge door  14  is a calibration cartridge port configured to receive the calibration cartridge  30 . 
     In exemplary embodiments, the device  10  includes a calibration door lock  23  located next to the door  14 . The calibration door lock  23  has a locked position and an unlocked position, and may be toggled between the two positions by a calibration door key. In some exemplary embodiments, the calibration door key is found in a calibration cartridge cover (described in further detail in the specification below). In other embodiments, the calibration door key may be found in other locations on the device  10 , or may be a separate piece from the device  10  or the calibration cartridge  30 . The calibration door key may be removed from the cover or other location and is configured to lock or unlock the calibration door lock  23 . When the door lock  23  is in the locked position, the calibration cartridge door  14  is locked and will not open. The calibration door lock  23  is configured to prevent tampering with the calibration cartridge  30 . In yet other embodiments, the door lock  23  is engaged by default when the door is closed and must be opened via a pass code entered via user interface keys (e.g. soft keys on a display, hard keys of a keypad, etc.). 
     The in vitro medical diagnostic device  10  may include one or more ports  24  (shown in  FIG. 3 ), in exemplary embodiments. These ports  24  are configured to receive cables or other connection mechanisms. The ports  24  may be used to connect the device  10  to other pieces of equipment (e.g. via a communication network), or may be used to upload or download information to the device  10 . The device  10  may also be configured to exchange data wirelessly, including through Wi-Fi, another wireless internet connection, or by any other wireless information exchange. The device  10  also includes a power input  19 , which may receive a power supply connection that charges or provides power to the device  10 . The device  10  also includes a speaker  21 , which may be used to transmit a noise or audible response to the user. The device  10  may also include a handle  26 , which can be used to carry the portable device  10 . The handle  26  rotates between two positions, depending on whether it is in use. In the illustrated embodiment of  FIG. 6 , the handle  26  is not in use, so it is rotated down and against the back surface of the device  10 , out of the way of the user. In exemplary embodiments, the device  10  may also include support legs  11  configured to allow the device  10  to rest on a table top or other surface. 
     The device  10  may also include a light source (e.g. LED) located to illuminate the assay cartridge  20 . The light source may be configured to illuminate the assay cartridge  20  to indicate testing status, or for any other purpose suitable for the particular application. The light source may be a fluorescent light, or may be any other type of light as necessary or desirable for the particular application. 
     The device  10  also includes a bar code scanner  15  that is built into the side of the device  10 , in exemplary embodiments. The bar code scanner  15  is configured to scan bar codes on test assay cartridges  20 , calibration fluid packs  54 , liquid quality control solutions, or any other items having scannable bar codes and for use with the device  10 . The bar code scanner  15  may also be used to scan a bar code tag representing patient or operator identification. In exemplary embodiments, the scanner  15  emits a beam that covers the bar code. If the bar code is scanned successfully, the device  10  will beep and the beam will turn off automatically. If the bar code is not scanned successfully, the device  10  will prompt the user through the display screen  18 , by emitting a noise, or by some other output. In an exemplary embodiment, the bar code scanner  15  is a one-dimensional bar code scanner. In other embodiments, the bar code scanner  15  is a two-dimensional scanner. 
     Referring now to  FIGS. 7-9 , the assay cartridge  20  is shown, according to an exemplary embodiment. The assay cartridge  20  includes a cartridge body  36 . In exemplary embodiments, the cartridge body  36  is at least partially transparent. The cartridge body  36  may be made from a molded plastic, or from another material, or set of material. The cartridge body  36  provides protection for the cartridge  20 . In the illustrated embodiment of  FIGS. 7-9 , at least one portion of the cartridge body  36  is covered with a thin film for sealing a channel or other components within the cartridge  20 . The thin film may reduce the total thermal mass to be heated by the device  10 . The cartridge has a top end (as shown in  FIG. 7 ) for receiving a syringe  25  having a biological sample, and a bottom end that is inserted into the diagnostic device  10 . The bottom end of the cartridge  20  is configured to insert into the testing slot  22  of the diagnostic device  10 . 
     The assay cartridge  20  includes a stop member  33 , in exemplary embodiments. The stop member  33  is located on the outside of the cartridge body  36  and is raised above the surrounding surface of the cartridge body  36 . The stop member  33  is configured to lock the assay cartridge  20  into the device  10 . One or more position detectors within the device  10  may be utilized to determine the position of the assay cartridge  20  (i.e. whether the cartridge is fully seated). A main board (shown in  FIG. 44 ) having a processor may be configured to track a position for the assay cartridge  20  using information from at least one position detector. Once the assay cartridge  20  has been fully inserted into the testing slot  22 , a locking rod  120  (shown in  FIG. 50 ) may actuate, protruding into a space adjacent (e.g. just above) to the stop member  33 , and between the stop member  33  and the opening of the testing slot  22 . Once the locking rod  120  is in this position, the cartridge  20  cannot be removed from the device  10  because the protruding surface of the stop member  33  is unable to clear the actuated locking rod  120 . In exemplary embodiments, the user may press the eject button  16  to retract the locking rod  120 , allowing the assay cartridge  20  to be removed from the testing slot  22 . In other exemplary embodiments, a motor assembly  100  (shown in  FIGS. 46-52 ) may automatically retract the locking rod  120  when the testing cycle has completed, allowing the assay cartridge  20  to be removed from the testing slot  22  without the user needing to manually activate an eject button  16 . In other exemplary embodiments, the assay cartridge  20  is pushed up and out of the testing slot  22  by an automated mechanism when the eject button  16  has been pressed, or when the motor assembly  100  has otherwise retracted the locking rod  120 . 
     The bottom end of the assay cartridge  20  also includes positioning slots  41  and  43  on each side of the cartridge  20 . The positioning slots  41  and  43  are configured to engage positioning rods. The positioning slots  41  and  43  are intended to protect needles  56  (illustrated in  FIG. 10 ) that project into the cartridge  20  to transmit fluid or air. The positioning slots  41  and  43 , guide the cartridge  20  into its testing position, protecting the needles  56  from bending or damage when the cartridge  20  is dislocated horizontally. 
     In exemplary embodiments, the assay cartridge  20  includes an inlet  34  located on the top end of the cartridge  20 . The inlet  34  houses an interface  38  (e.g. needle) for connecting to a receptacle (e.g. syringe, capillary tube, etc.) containing a fluid sample  39 . The assay cartridge  20  also includes a C-shaped structure  37  that is located within the inlet  34 . In exemplary embodiments, the C-shaped structure  37  is a sleeve for the syringe  25 , holding the tip of the syringe  25  within the inlet  34 . The receptacle introduces the fluid sample  39  to the assay cartridge  20  for testing. The fluid sample  39  is received through the interface  38 , and enters a fluid channel  32  within the cartridge  20 . In some exemplary embodiments, the length of the interface  38  from the tip of the interface  38  to the end of the C-shaped structure  37  is approximately 21.6 mm, but may be another length in other embodiments. 
     In exemplary embodiments, the fluid channel  32  is fluidly connected to the testing portion  42  located on the bottom of the cartridge  20 . The fluid channel  32  is configured to route the sample  39  to the testing portion  42 . The testing portion  42  includes an array comprising a plurality of electrochemical sensors  40  for testing the fluid sample  39 . The electrochemical sensors  40  are configured to communicate with hardware (illustrated in  FIG. 44 ) within the diagnostic device  10  to provide diagnostic information to the user. The testing portion  42  is fluidly connected to a waste area  35  downstream of the fluid channel  32 . In exemplary embodiments, the waste area  35  holds spent fluids, such as a calibration fluid. 
     The fluid channel  32  may have a larger or smaller diameter at certain points throughout the flow path (i.e. fluid channel  32 , waste area  35 , etc.). For instance, the fluid channel  32  may ramp up prior to or as it enters the testing portion  42 , providing a smaller flow area or diameter. The fluid channel may then open up in the testing portion  42 , creating larger area or diameter channels over the sensors  40  for holding and testing the fluid sample  39 . The fluid channel  32  may also contain these “ramped” areas (i.e. areas where the fluid channel changes diameter) in portions of the waste area  35 . These ramped areas within the waste area may be configured to keep a larger used volume of the calibration fluid within the waste area, preventing the fluid sample  39  from being contaminated. The ramped areas may also be present to slow down fluid flow within an area of the fluid channel  32 . 
       FIG. 7  is a perspective view of an assay cartridge for insertion into the medical diagnostic device, according to an exemplary embodiment.  FIG. 8  is a front view of the assay cartridge of  FIG. 7 .  FIG. 9  is a back view of the assay cartridge of  FIG. 7 . 
     Referring now to  FIGS. 10A-C , a schematic view of a system provided by the diagnostic device  10  is shown according to an exemplary embodiment, including the assay cartridge  20  as inserted into the diagnostic device  10 , a fluid path, and a pump. According to the illustrated embodiment of  FIG. 10A , the assay cartridge  20  is fluidly connected to the calibration cartridge  30  on a first side, and connected to a vacuum pump  50  on a second side. In exemplary embodiments, the calibration cartridge  30  is configured to introduce gas or fluid into the assay cartridge  20  through a T connector  52  (shown in more detail in  FIGS. 28-43 ). The T connector (i.e. air and gas junction)  52  may connect to the assay cartridge  20  by a needle  56  or another connection mechanism. 
     One or more pinch valves  46 - 48  control the sequence of gas or fluid flows from the calibration cartridge  30  to the assay cartridge  20 . In exemplary embodiments, two pinch valves  47  and  48  regulate the introduction of calibration fluid and air into the assay cartridge  20 , while one pinch valve  46  regulates the introduction of the fluid sample  39  into the testing portion  42 . In other embodiments, a different system of pinch valves may regulate the flow of fluid in the cartridge  20 . 
       FIG. 10A  shows a fluid flow path through the assay cartridge  20 . In exemplary embodiments, the inlet  34  receives a syringe  25 , or other receptacle such as a capillary tube, filled with the fluid sample  39  (i.e. biological sample). The interface  38  of the inlet  34  enters the tip of the syringe  25  and protrudes into the fluid sample  39 . The interface  38  is fluidly connected to the fluid sample  39  within the syringe  25 , and fluidly connects the fluid sample  39  to the fluid channel  32 . 
       FIG. 10B  shows a linear pathway for the fluid sample  39  to flow through the fluid channel  32  and into the testing portion  42 . The fluid flow is unidirectional, in exemplary embodiments. Fluid may flow from the syringe  25  (or other receptacle) to the pinch valve  46  in the assay cartridge  20 . From the pinch valve  46 , the fluid flows in a single direction. The pinch valve  46  is configured to open and close, controlling (e.g. allowing or preventing) the introduction of the fluid sample  39  into the testing portion  42 . The fluid travels through the fluid channel  32 , through the testing portion  42 , and if necessary, into the waste area  35 . 
     Once the fluid channel  32  is filled, the pressure in the fluid channel  32  dissipates and fluid is prevented from flowing out of the disposable assay cartridge  20 . The volume of the fluid channel  32  may be known and accordingly a complementary volume of fluid allowed into the channel  32  may be controlled to prevent overflow of the cartridge  20 . In exemplary embodiments, the fluid (e.g. fluid sample  39 , calibration fluid, etc.) used during a testing procedure is completely contained within the assay cartridge  20 . As can be seen in the illustration of  FIG. 10A , there is no fluid communication from the assay cartridge  20  to any surface of the diagnostic device  10  and no fluid communication from the calibration cartridge  30  to any surface of the diagnostic device  10 . The assay cartridge  20  is removable and disposable. Accordingly, there is no fluidic circuitry inside the diagnostic device  10 , which may reduce the potential risks and cleaning requirements associated with fluidic circuitry. The self-contained assay cartridge  20  is intended to prevent repairs or maintenance due to fluid leaking and corroding sensitive electronics in the device  10 , potentially reducing the maintenance costs associated with the device  10 . The fluid sample  39  (or other fluid) travels through the cartridge  20  uni-directionally, is completely contained within the cartridge  20  (during and even after testing), and does not enter any other part of the device  10 . 
     In exemplary embodiments, the vacuum pump  50  is also fluidly connected to the fluid channel  32 . The vacuum pump  50  may be powered on and off and controllably operated by the diagnostic device  10 . When the vacuum pump  50  is powered on, it may create a controlled negative pressure in the assay cartridge  20 , driving the fluid sample  39  to flow from the syringe  25  and into the fluid channel  32 . A pinch valve  46  may be used to open or close the fluid channel  32 , allowing the fluid sample  39  to travel into the testing portion  42 . Pinch valves  48  and  47  are also used to control the introduction of atmospheric air and calibration fluid, respectively, from the calibration cartridge  30  to the assay cartridge  20 . The pinch valves  46 - 48  may be controlled by control hardware (illustrated in  FIG. 44 ) within the device  10 , and opened or closed in sequence to complete the testing cycle. 
     By controllably powering the vacuum pump  50  on or off, and opening or closing the pinch valves  46 - 48 , the calibration fluid, atmospheric air (or another gas), and fluid sample  39  may enter the assay cartridge  20  in a designated sequence. In exemplary embodiments, the calibration fluid enters the assay cartridge  20  first. The pinch valve  47  is controllably opened, and the pinch valves  46  and  48  are controllably closed. Calibration fluid is then pumped from the calibration cartridge  30  to the assay cartridge  20 , and into the testing portion  42 . The calibration fluid is held in the testing portion  42  for a predetermined amount of time, heated to a predetermined temperature, and used to calibrate the device  10 . Once the device  10  has been calibrated, the pinch valve  48  is controllably opened and the pinch valves  46  and  47  are controllably closed. Air is then pumped from the calibration cartridge  30  into the testing portion  42 . The air pushes the calibration fluid into the waste area  35 , clearing the testing portion  42 . Once the calibration fluid has been cleared from the testing portion  42 , the pinch valve  46  is controllably opened, and the pinch valves  47  and  48  are controllably closed. The fluid sample  39  is then pumped into the testing portion  42 , where the sample  39  is heated and tested. Once the fluid sample  39  has been tested by the device  10 , the testing cycle is complete and the assay cartridge  20  may be ejected. 
     In some exemplary embodiments, the pinch valves  46 - 48  may be integrated pinch valves, having a thin film that is elastically biased out and can be closed by applying pressure in toward the cartridge  20  or  30 . In these embodiments, the pinch valves  46 - 48  include flexible film areas  76  (shown in  FIG. 25 ). The pinch valves  46 - 48  may be constructed at least in part with polyethylene terephthalate. A pinch valve actuator  78  (e.g. movable lever) may be applied to the pinch valves  46 - 48  to open or close the pinch valves  46 - 48 . The pinch valve actuator  78  may open or close the valves  46 - 48  by applying or removing pressure. The pinch valves  46 - 48  may close under pressure and open in the absence of pressure. Once the pinch valve  46  is open, the fluid sample  39  can travel from the syringe  25  or other receptacle, through the fluid channel  32 , and to the testing portion  42 . 
     Referring now to  FIG. 10C , the connection (i.e. gas inlet or outlet) between the assay cartridge  20  and the calibration cartridge  30  is represented. In exemplary embodiments, the connection between the assay cartridge  20  and the calibration cartridge  30  includes a rubber seal  53 , which forms a fluid seal at the needle  56 . In these embodiments, the rubber seal  53  is attached to the T connector  52 , and is configured to ensure a sealed connection for the fluid flow path between the assay cartridge  20  and the calibration cartridge  30 . In exemplary embodiments, the rubber seal  53  is pierced to establish fluid communication between the calibration fluid channel  88  and the assay cartridge  20 . The rubber seal  53  may be made from a septum comprising silicone, or any other material suitable for the application. 
     The fluid connection between the assay cartridge  20  and the vacuum pump  50  is similar to the connection shown in  FIG. 10C . The connection between the assay cartridge  20  and the vacuum pump  50  includes a rubber seal  53  forming a fluid seal at the needle  56 . The rubber seal  53  is attached to the vacuum pump  50  (i.e. forming a pumping system), and is configured to provide a fluid flow path between the assay cartridge  20  and the vacuum pump  50 . The fluid flow path may be fluidly sealed. In exemplary embodiments, the assay cartridge  20  is also tapered at both connections in order to receive the needles  56 , and is configured to establish a fluid seal. The rubber seal  53  may be made from a septum comprising silicone, or any other material suitable for the application. 
     Referring briefly to  FIGS. 11A-C , a schematic representation of a calibration cartridge  30  connected to an alternative assay cartridge  60  is shown, according to an alternative embodiment. The connection forms a fluid path for the fluid flow actuated by the pump  50 . The alternative assay cartridge  60  is shown more particularly in  FIGS. 15-17 , and described later within this specification. 
     Referring now to  FIG. 12 , a simplified back view of the assay cartridge  20  is shown, according to an exemplary embodiment. The assay cartridge  20  is configured to receive the fluid sample  39  through the interface  38 . The fluid sample  39  is routed through the fluid channel  32 , and then to the testing portion  42 . The testing portion  42  includes a plurality of sensors  57 , including electronic sensors  571  and  572 . In the illustrated embodiment of  FIG. 12 , the electronic sensors  571  and  572  are configured to control the volume of fluid introduced into the assay cartridge  20 . In exemplary embodiments, the assay cartridge  20  includes an overflow prevention sensor  573  positioned within the waste area  35 . The overflow prevention sensor  573  is configured to send one or more signals to processing electronics when fluid reaches the overflow prevention sensor  573 . The processing electronics are configured to stop the flow of fluid into the assay cartridge  20  one or more signals are received from the sensor  573 . 
     Referring now to  FIGS. 13-14 , the function of the electronic fluid sensors  57  is shown.  FIG. 13  shows a linear representation of the fluid flow path through the assay cartridge  20 . The fluid flows through the fluid channel  32  and over the multiple sensors  57 . The sensors  57  are located within the testing portion  42  and are configured to facilitate the accurate dispensing of predetermined volumes of fluid into the fluid channel  32 . The electronic fluid sensors  57  include conductance poles  59  that are configured to detect high or low impedance (i.e. whether fluid is flowing over the sensor). Prior to the flow of fluid through the fluid channel  32 , the two poles  59  of a first electronic sensor  571  are in a high impedance “off” state (see fluid state A of  FIG. 14 ). As fluid flows over the electronic sensor  571 , the impedance remains high until the space between the two poles  59  is filled with fluid and fluid covers both poles  59  of the first sensor  571 . At that point, the sensor  571  is in a low impedance “on” state (see fluid state B of  FIG. 14 ). In the illustrated embodiment of  FIG. 12 , the assay cartridge  20  includes a second electronic sensor  572  that is similar in function to the first electronic sensor  571 . In other exemplary embodiments, the assay cartridge  20  may include any number of electronic sensors  57 , as is necessary for the particular application. 
     In exemplary embodiments, the diagnostic device  10  includes a main board (shown in  FIG. 44 ). The main board is part of a processing circuit (i.e. processing electronics), having a processor and memory. The main board receives one or more signals from the sensors  57 , and is configured to turn the vacuum pump  50  on or off depending on the signals received from the electronic sensors  57 . In the illustrated embodiment of  FIG. 12 , the electronic sensors  571  and  572  are configured to control the volume of fluid introduced into the assay cartridge  20 . For instance, once the sensor  571  is in the “on” state, the main board may send a signal to turn off the vacuum pump  50 , eliminating the negative pressure in the fluid channel  32  and stopping the fluid from flowing. The assay cartridge  20  may include any number of electronic sensors  57  configured to control the volume of fluid within the cartridge  20 . The sensors  57  may be positioned at different points on the fluid flow path (e.g. within the testing portion  42 , within the waste area  35 , etc.), controlling the volume of fluid within the cartridge  20  according to what is suitable for the particular application. 
     Referring still to  FIGS. 13-14 , the assay cartridge  20  may also include an overflow prevention sensor  573 , in exemplary embodiments. The overflow prevention sensor  573  has two poles  59  that are configured to detect high or low impedance. When the overflow prevention sensor  573  detects low impedance between its two poles  59 , the main board may send a signal to the vacuum pump  50  (or to a controllable syringe  25 , in an alternative embodiment) to immediately stop fluid flow to the channel  32 . In exemplary embodiments, the overflow prevention sensor  573  operates as an emergency stop, intended to be used only when there is a failure somewhere in the system. In these exemplary embodiments, sensors  571  and  572  are configured to help control the volume of fluid introduced into the cartridge  20 . The sensors  571  and  572  may be configured to communicate with the main board when fluid reaches the sensors  571  and  572 . The main board may then send a signal to turn off the vacuum pump, eliminating the negative pressure in the fluid channel  32  and stopping the fluid from flowing. The overflow prevention sensor  573  serves as a safety to stop the fluid flow and to prevent the cartridge  20  from overflowing. In other exemplary embodiments, the overflow prevention sensor  573  may provide a signal to the main board, stopping the calibration fluid from flowing out of the cartridge  20 . Before the fluid sample  39  is sent into the testing portion  42  for testing, the calibration fluid is pushed into the waste area  35 . The overflow prevention sensor  573  may help prevent the calibration fluid from flowing further than a predetermined point within the waste area  35  by providing a signal to the main board. In response to the signal from the overflow prevention sensor  573 , the main board can send a signal to turn off the vacuum pump  50 , eliminating the negative pressure in the cartridge  20  and stopping the fluid from flowing to the cartridge  20 . Therefore, the overflow prevention sensor  573  is intended to ensure that no fluid sample  39  or other fluid can leak into the rest of the device  10 . In other embodiments, the main board may send a signal to reverse the flow of the vacuum pump  50 , pushing fluid back through the channel  32  and preventing fluid from overflowing the cartridge  20 . The assay cartridge  20  may include any number of electronic sensors  57  configured to supply signals to the main board in order to prevent fluid overflow. For example, the assay cartridge  20  may include multiple overflow prevention sensors  573  staggered throughout the waste area  35 , each sensor  573  configured to stop fluid flow when fluid reaches the sensor  573 . 
       FIGS. 15-16  illustrate the alternative cartridge  60 . In  FIGS. 15-16 , the placement of the electronic sensors  57   a  are shown, according to an alternative embodiment. In the illustrated embodiment of  FIGS. 15-16 , the assay cartridge  20  includes four electronic sensors  571   a ,  572   a ,  573   a , and  574   a . The electronic sensors  571   a ,  572   a , and  573   a  are configured to allow a predetermined amount of fluid to enter the fluid channel  32   a  of the assay cartridge  60 .  FIG. 15  illustrates the assay cartridge  60  as fluid reaches the first electronic sensor  571   a , while  FIG. 16  illustrates the cartridge  60  as fluid reaches the overflow prevention sensor  573   a .  FIG. 17  shows a linear pathway where the fluid sample  39  can flow through the fluid channel  32   a  and over the sensors  57   a , according to the alternative embodiment of  FIGS. 15-16 . 
     Referring now to  FIG. 18 , the receiver  34  of the assay cartridge  20  has a universal design, such that it is configured to receive more than one size receptacle (i.e. syringe  25 ). For example, the receiver  34  may receive a 1 ml, 3 ml, or a 5 ml syringe  25 . However, in other exemplary embodiments, the receiver  34  may be sized differently or otherwise configured to receive any other size syringe  25 . The syringe  25  may be inserted into the receiver  34 . Once inside the receiver  34 , the tip of the syringe  25  is fit into a C-shape structure  37 , connecting with the interface  38 . The fluid sample  39  is then aspirated into the interface  38 . In exemplary embodiments, air flows through the C-shape structure  37  and into the area between the tip of the syringe  25  and the interface  38 , replacing the sample  39  that is aspirated into the fluid channel  32 . The receiver  34  may also be configured to receive a capillary tube (shown more particularly in  FIG. 21 ). In exemplary embodiments, the interface  38  is adapted to mate with the receptacle (i.e. syringe  25 , capillary tube, etc.) either directly or through an adapter. 
     Referring to  FIGS. 19-20 , an alternative syringe configuration is shown, according to an exemplary embodiment.  FIG. 19  is a front view of an assay cartridge  90  with a syringe  25  loaded from the top, according to an alternative embodiment.  FIG. 20  is a front view of the assay cartridge  90  of  FIG. 19 . The alternative assay cartridge  90  includes a receiver  34   b  with an opening on the top of the cartridge  90 . In this embodiment, the syringe  25  is introduced vertically, and connected to a slide  62 . The cartridge  90  has a needle  66  attached to the end of the fluid channel  32   b , which engages the end of the syringe  25 . The cartridge  90  also includes a rubber seal ring  64  that seals the connection between the syringe  25  and the needle  66 . In exemplary embodiments, the slide  62  moves vertically relative to the rest of the cartridge  90  when pressure is applied to the syringe  25  (shown in  FIG. 20 ), and the needle  66  protrudes into the fluid sample  39 . When the vacuum pump  50  is powered on, the fluid sample  39  from the syringe  25  flows into the fluid channel  32   b.    
     Referring now to  FIGS. 21-22 , a capillary tube is shown connected to the assay cartridge, according to exemplary embodiments.  FIG. 21  is a back view of the assay cartridge  20  with the capillary tube  74  and capillary tube adapter  72  coupled to the assay cartridge  20 , according to an exemplary embodiment.  FIG. 22  is a back view of the assay cartridge  60  with the capillary tube  74  and capillary tube adapter  72  coupled to the assay cartridge  20 , according to an exemplary embodiment. In these embodiments, a rubber or silicone capillary tube adapter  72  may be placed in the receiver  34  or  34   a  so that a small sample volume can be delivered with a capillary tube  74 . One end of the capillary tube adapter  72  is connected with the capillary tube  74 , and the other end is connected to the needle  56  or  56   a  in order to form a fluid path. The vacuum pump  50  may be powered on, producing a negative pressure in the assay cartridge  20  or  60 , and forcing the fluid sample  39  to flow through the needle  56  and into the fluid channel  32  or  32   a . Capillary tubes  74  may be used to test low volume fluid samples or used in other applications where capillary tubes  74  are used. The end wall of the inlet  34  has one or more holes configured to allow air to discharge when the capillary tube adapter  72  is plugged by the capillary tube  74  (i.e. does not allow fluid to pass). 
     Referring now to  FIGS. 23-25 , a pinch valve  46  and related pinch valve actuator  78  for controlling the movement of the fluid sample  39  (i.e. valve control mechanism) within an assay cartridge  20  is shown, according to an exemplary embodiment. The assay cartridge  20  includes a pinch valve  46  that opens and closes, controlling the movement of the fluid sample  39  into the fluid channel  32 . A pinch valve actuator  78  within the device  10  may manipulate the pinch valve  46 , pressing against the valve  46  and causing the valve  46  to controllably open or close.  FIG. 24  illustrates how the pinch valve actuator  78  contacts the valve  46  in exemplary embodiments, closing the valve  46  by pushing against it, and opening the valve  46  by pulling away from the cartridge  20  and the valve  46 . When the pinch valve  46  is closed, as in  FIG. 25A , the fluid sample  39  is prevented from reaching the fluid channel  32  for testing. However, when the pinch valve  46  is open, as in  FIG. 25B , the fluid sample  39  is allowed to enter the testing portion  42 . In exemplary embodiments, the fluid sample  39  is pulled into the fluid channel  32  by negative pressure created by the vacuum pump  50 . 
       FIG. 23  is a perspective view of the assay cartridge  20 , including the valve actuator  78  engaging the pinch valve  46  on the assay cartridge  20 , according to an exemplary embodiment.  FIG. 24  is a cross-sectional side view of the assay cartridge  20  of  FIG. 23 , including the valve actuator  78  actuating the pinch valve  46  on the assay cartridge  20 , according to an exemplary embodiment.  FIG. 25  is a cross-sectional illustration of the pinch valve  46  in the closed and open position, according to an exemplary embodiment.  FIGS. 26-27  illustrate the interaction between the pinch valve actuator  78  and the pinch valve  46 , according to an alternative embodiment. 
       FIG. 28  is a perspective semi-transparent view of the calibration cartridge  30 , according to an exemplary embodiment.  FIG. 29  is a cross-sectional side view of the calibration cartridge  30  of  FIG. 28 , including a fluid pack  54 , according to an exemplary embodiment.  FIG. 30  is a close up cross-sectional view of a rod valve  83  of the calibration cartridge  30  of  FIG. 28 , including the rod valve  83  in the open and closed position, according to an exemplary embodiment.  FIG. 31  is a cross-sectional illustration of the calibration cartridge  30  of  FIG. 28 , including a T connector  52 , and a fluid path and an air path from the calibration cartridge  30 , according to an exemplary embodiment. 
     Referring now to  FIGS. 28-31  in more detail, a calibration cartridge is shown, according to an exemplary embodiment. The calibration cartridge  30  is disposable and removable. The calibration cartridge  30  includes a housing  82  that is intended to protect a fluid pack  54 . The housing  82  is made of plastic, in exemplary embodiments, but may be made of another material or set of materials. The calibration cartridge  30  may also include a calibration cartridge cover (not shown). The cover is connected to a front portion (according to  FIG. 28 ) of the cartridge  30 , in exemplary embodiments. The calibration cartridge cover is intended to protect the calibration cartridge  30  when the cartridge  30  is not in use (i.e. not inserted into the diagnostic device  10 ). 
     The fluid pack  54 , or chamber, is fluidly connected to the T connector  52 . The fluid pack  54  may be a soft, flexible fluid pouch filled with unused calibration fluid. The T connector  52  includes a fluid flow channel  84 , or pipe. The fluid flow channel  84  is configured to receive calibration fluid from the fluid pack  54 , and to provide calibration fluid to a fluid channel  88  connecting to the assay cartridge  20 . In exemplary embodiments and when the calibration cartridge  30  is fluidly connected to the assay cartridge  20 , the height of the fluid flow channel  84  is higher than the height of the pinch valve  46 . The T connector  52  also includes an air flow channel  86  that connects the T connector  52  to atmospheric air (i.e. ambient air), enabling the T connector  52  to send the air to the assay cartridge  20  as necessary. The fluid flow channel  84  and the air flow channel  86  meet at the T connector  52 , forming a junction. In exemplary embodiments, a the calibration cartridge  30  includes a cap to close both the air and fluid ports during transport and storage. The calibration cartridge  30  may also include an L-shaped connector  122  (shown further in  FIGS. 53A-C ), in exemplary embodiments. The L-shaped connector  122  is configured to fluidly connect the fluid pack  54  to the T connector  52 , thus providing a fluid connection to the assay cartridge  20 . The L-shaped connector  122  is described in further detail below. 
     In exemplary embodiments, the calibration fluid flows through the T connector  52  to the needle  56  of the calibration cartridge  30 . In these embodiments, the needle  56  is inserted into the assay cartridge  20  and is configured to supply the assay cartridge  20  with calibration fluid. A rubber insert  61  provides a seal around the connection between the needle  56  and the assay cartridge  20 , in exemplary embodiments. The flow of calibration fluid and atmospheric air is controlled by pinch valves  47  and  48 , respectively. The pinch valve  47  is located at the fluid flow channel  84 , and the pinch valve  48  is located at the air flow channel  86 . The pinch valves  47  and  48  are configured to open and close, regulating the introduction of fluids and gases (e.g. atmospheric air, calibration fluid, etc.) to the assay cartridge  20 . In exemplary embodiments, when the vacuum pump  50  is controllably powered, fluid or gas flows through channel  84  or  86 , travels through the needle  56 , and enters the assay cartridge  20 . In some exemplary embodiments, the fluid channel  88  provides a mixture of fluid and gas into the assay cartridge  20 . In other exemplary embodiments, the fluid channel  88  provides either a fluid or a gas to the assay cartridge  20 . The calibration cartridge  30  may introduce an air bubble to displace at least a portion of any calibration fluid previously introduced into the calibration fluid channel  88 . 
     Referring still to  FIG. 30 , a rod valve of the calibration cartridge is shown, according to an exemplary embodiment. The calibration cartridge includes a rod valve  83 , which moves between an open and closed position. During production, transport, and storage, the rod valve  83  may remain in the closed position, as in  FIG. 30A . When in the closed position, the rod valve  83  is caused to press tightly against the fluid flow channel  84  (e.g. via a spring bias), sealing the calibration fluid in the fluid pack  54  from flowing to the needle  56  prior to engagement with the assay cartridge  20 . In  FIG. 30B , the rod valve  83  is in the open position. The rod valve  83  is in the open position after the calibration cartridge  30  has been installed to the diagnostic device  10 . Calibration fluid may then be drawn into the assay cartridge  20 . When the fluid pack  54  is engaged with the assay cartridge  20 , the rod valve  83  is removed and in the open position, but the calibration fluid does not flow because the pinch valve  47  maintains a seal by pinching the T connector  52 . 
     Referring now to  FIGS. 32-34 , the pinch valves  47  and  48  are aligned to the calibration fluid flow channel  84  and the air flow channel  86 , respectively. The pinch valve actuators  78  are configured to push up against the pinch valves  47  and  48  on the calibration cartridge  30 , closing the pinch valves  47  and  48  to prevent fluid or air from leaving the T connector  52 .  FIG. 33  shows the location of the pinch valves  47  and  48  on the calibration cartridge  30 . The pinch valves  48  and  47  are aligned to pinch the fluid pathways for air and calibration fluid, respectively, in exemplary embodiments.  FIGS. 34A-B  show a cross-section of the pinch valves  47  and  48  in the closed position ( FIG. 34A ), and in the open position ( FIG. 34B ).  FIG. 32  is a perspective view of the calibration cartridge  30  and two pinch valve actuators  78 , according to an exemplary embodiment.  FIG. 33  is a cross-sectional side view of the calibration cartridge  30 , including a fluid pack  54 .  FIG. 34  is a cross-section view of a calibration cartridge pinch valve  47  or  48  in the open and closed positions, according to an exemplary embodiment. 
       FIG. 35  is a perspective and semi-transparent view of a calibration cartridge  80 , according to an alternative embodiment.  FIG. 36  is a cross-sectional view of the alternative calibration cartridge  80 , including a fluid pack  54   a  and the T connector  52 .  FIG. 37  is a perspective view of the alternative calibration cartridge  80  and a cross-sectional view of the alternative calibration cartridge  80  showing the rod valve  83   a  in the closed position.  FIG. 38  is another perspective view of the alternative calibration cartridge  80  and a cross-sectional view of the alternative calibration cartridge  80  showing the rod valve  83   a  in the open position. 
     Referring now to  FIGS. 35-36 , the alternative calibration cartridge  80  is shown. The alternative calibration cartridge  80  has a alternative rod valve  83   a , which is shown more particularly in  FIGS. 37-38 . In the illustrated embodiment of  FIG. 37 , the rod valve  83   a  presses tightly against the channel  84   a , preventing the fluid from flowing out of the channel  84   a , and sealing the calibration fluid from flowing to the fluid output (i.e. the needle  56   a ). In order to allow calibration fluid flow, the rod valve  83   a  is caused to disengage. Once the calibration cartridge  80  is inserted into the device  10 , for instance, the rod valve  83   a  is released so that the pressure is relieved and the flow is not restricted, allowing calibration fluid to flow out of the channel  84   a . In  FIG. 38 , the rod valve  83   a  has been released, opening the channel  84   a  for calibration fluid to flow through. Once the calibration cartridge  30  has been removed from the device  10 , the rod valve  83   a  is caused to return to the closed position (e.g. via a spring bias) to keep the remaining calibration fluid within the cartridge  80 . 
     Referring now to  FIGS. 39-41 , the calibration cartridge  80  is shown according to an alternative embodiment. In  FIGS. 39-41 , pinch valve actuators  78   a  are shown as aligned with the pinch valves  47   a  and  48   a . The pinch valve actuators  78   a  are configured to cause the pinch valves  47   a  and  48   a  to close by pinching respective portions of the fluid pathways  85   a . The pinch valves  48   a  and  47   a  may include a flexible film area which may elastically press in toward the cartridge  80 , closing the pinch valves  48   a  and  47   a  and restricting the flow of fluid and/or air. The pinch valves  48   a  and  47   a  are closed by pinch valve actuators  78   a , in exemplary embodiments.  FIG. 39  is another perspective view of the alternative calibration cartridge  80 , showing pinch valve actuators  78   a  engaging the pinch valves  48   a  and  47   a  of the calibration cartridge  80  to regulate fluid and/or gas flow.  FIG. 40  is a cross sectional view of the calibration cartridge  80 , including pinch valves actuators engaging the pinch valves  48   a  and  47   a  of the calibration cartridge  80 . The pinch valves  48   a  and  47   a  include rubber spacers  96  configured to create a fluid pathway  85   a .  FIG. 41  is a close up cross-sectional view of the pinch valve  47   a  for the fluid path in the open and closed positions, and a cross section view of the T connector  52  forming a fluid pathway with the rubber spacers  96 . 
       FIG. 39  is another perspective view of the calibration cartridge  80 , showing pinch valve actuators  78   a  engaging the pinch valves  48   a  and  47   a  of the calibration cartridge  80  to regulate fluid and/or gas flow, according to an exemplary embodiment.  FIG. 40  is a cross-sectional view of the calibration cartridge  80 , including pinch valve actuators  78   a  engaging the pinch valves  48   a  and  47   a  of the calibration cartridge  80 .  FIGS. 41A-B  are close up cross-sectional views of a calibration cartridge pinch valve  48   a  or  47   a  in the closed and open positions, respectively, according to an exemplary embodiment. 
     Referring now to  FIGS. 42-43 , an alternative embodiment of the T connector  52  is shown.  FIG. 42  is a close up cross-section view of a fluid pathway for the calibration cartridge  30 , including a thin film formed over two rubber spacers  96 , according to an exemplary embodiment.  FIG. 43  is a close up cross-section view of a fluid pathway formed with a thin film  95  over an inserted tube. In this embodiment, the T connector  52  includes tubes  94  (shown in  FIG. 43B ) that are inserted between a thin film  95 .  FIG. 42B  shows a cross-section of the T connector  52 . Two rubber spacers  96  are sealed by the thin film  95 , creating an air channel  97  within the T connector  52 . In exemplary embodiments, the air channel  97  is made from dispensed silicon, but may be made from any other materials suitable for the application in other exemplary embodiments. The pinch valve may press tightly against the channel  97  in exemplary embodiments, regulating the opening and closing of the channel  97 . 
     In the illustrated embodiment of  FIGS. 42-43 , the rubber spacers  96  are made from silicone and the thin film  95  is made of aluminum-plastic. However, in other exemplary embodiments, the rubber spacers  96  may be made of any other type of polymer or other suitable material, and the thin film  95  may be made of any material suitable for the particular application. The thin film  95  may be sealed over the rubber spacers  96  by “hot pressing,” (a metallurgy process achieved by simultaneous application of heat and pressure) or by any other means suitable for sealing the air channel  97 . In exemplary embodiments, the rubber spacers  96  have a concave dent configured to guide the needle  56  to pierce the thin film  95  rather than punch through the spacers  96 . 
     Referring now to  FIG. 44 , a hardware organization diagram is shown for an in vitro medical diagnostic device  10 , according to an exemplary embodiment. In exemplary embodiments, the ADC and DAC communicate with a plurality of electrochemical sensors  40  and with any other input or output devices, such as position sensors or heating elements  116 . The electrochemical sensors  40  are located in the testing portion  42  of the assay cartridge  20 . The sensors  40  are used by the processing electronics of the diagnostic device to interpret the chemical composition of the fluid within the testing portion  42 . The ADC is configured to process analog signals from the electrochemical sensors  40 . Once the ADC processes the output from the sensors  40 , it may transmit the data to the analog control board. While the analog control board is named “analog control board” here and in the figures, it should be appreciated that the analog control board may include digital processing. The analog control board may utilize a DAC to convert digital outputs (on/off modulated signals) to analog signals (e.g., for the electrochemical sensors). For example, the DAC is used to control the applied potential for amperometric sensors. 
     Referring still to  FIG. 44 , each board shown (i.e., the connect board, the analog control board, the power control board, and the main board, etc.) may be implemented as a separate printed circuit board (PCB), integrated on the same PCB, or a combination of otherwise integrated and distributed. Each board may be considered processing electronics or a processing circuit. The processing electronics may include discrete components and/or integrated circuits. The power control board, for example, may include all discrete electronics components. Each board may include one or more processors. The processors may be variously implemented as general purpose processors, one or more application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable electronic processing components. Each board may also include one or more memory devices. The memory of each board may be one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage, etc.) for storing data and/or computer code for completing and/or facilitating the various processes described herein. The memory may be or include non-transient volatile memory and/or non-volatile memory. The memory may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described herein. The memory may be communicably connected to the processor and includes computer code modules for executing one or more processes described herein. 
     Referring still to  FIG. 44 , the analog control board can be coupled to more than one stepper motors. While one stepper motor is shown as coupled to the pump, another stepper motor may be coupled to a motor for a motor assembly  100  having a cam plate  102  (e.g., shown in  FIGS. 46-52 ). The motor assembly  100  may be configured to control one or more valves  46 - 48 , regulating the introduction of fluid into the assay cartridge  20 . The motor assembly  100  is shown and further in  FIGS. 46-52  and described further below. In yet other embodiments, the analog control board may be coupled to solenoids for control thereof. The main board may include a general purpose processor and memory. The memory of the main board may include a Linux environment or another operating system. The main board may variously trigger routines and other software existing on the analog control board. It should be noted that the analog control board may include its own operating system and software modules for conducting its activities as described herein. 
     The main board and the sub-boards may operate in concert as illustrated in  FIG. 45 . A data software manager may exist with the operating environment of the connect board. In other embodiments, the data manager may exist across the main board and the connect board. The analog control board may receive commands and function calls from the main board. The power control board may also receive commands and function calls from the main board. It should be noted that the power control board can control a variety of input and output activities beyond mere power supply management to the devices. For example, communications may be managed. The UART scanner may be a barcode scanner (e.g., 1D, 2D, etc.) as described herein. Data may be received at the main board from any of the sub-boards. 
     Referring now to  FIG. 46 , a perspective view of a motor assembly  100  for controlling pinch valve actuators  78  is shown, according to an exemplary embodiment. The motor assembly  100  includes a cam plate  102 . In exemplary embodiments, four plungers  108  and  106  (i.e. pinch valve actuators  78 ) are aligned with one or more pinch valves  46 - 48  or other valves. The plungers  108  and  106  are adjacent to and configured to receive the cam plate  102 , resting on concentric circles  104  on the cam plate  102 . Three plungers  108  are aligned with pinch valves  46 - 48  and are configured to open and close the pinch valves  46 - 48 , depending on the stage of the device  10  in the testing sequence. The plungers  108  are pressed against the pinch valves  46 - 48 , causing them to remain closed until the plungers  108  are actuated. A fourth plunger  106  is aligned with the pogo pins  114  (shown in  FIG. 47 ) and heating elements  116  (i.e. heating plates or heating pads, shown in  FIG. 47 ). The fourth plunger  106  is configured to cause the heating elements  116  to close over the testing portion  42  when the plunger  106  is actuated, heating the fluid (e.g. fluid sample  39 ) within the testing portion  42 . The heating elements  116  are intended to cause a substantially constant temperature gradient to exist between two or more heating elements  116  on each side of the assay cartridge  20 . The fourth plunger  106  is also configured to actuate the pogo pins  114 , locking the assay cartridge  20  into a testing position. 
     The cam plate  102  is configured to rotate. As the cam plate  102  rotates, the plungers  108  and  106  “ride” along the concentric circles  104  of the cam plate  102  (i.e. make contact with the cam plate  102  as it rotates, rising and falling with the contours of the plate  102 ). Each of the concentric circles  104  has one or more raised portions  112 . When one of the plungers  108  rides over one of the raised portions  112  of the concentric circle  104 , the plunger  108  is pulled away from its associated pinch valve  46 ,  47 , or  48 , which will cause the associated valve  46 ,  47 , or  48  to open. 
     Referring now to  FIG. 47 , a side view of the motor assembly  100  for controlling plungers  108  and  106  (i.e. pinch valve actuators) is shown, according to an exemplary embodiment. The heating elements  116  and the pogo pins  114  are associated with the fourth plunger  106 . The fourth plunger  106  may actuate the heating elements  116  and pogo pins  114  when it rides over the raised portion  112  of the cam plate  102 , causing the heating elements  116  to contact both sides of the testing portion  42 . The fourth plunger may also cause the pogo pins  114  to contact the electrochemical sensors  57  of the cartridge  20 . When the fourth plunger  106  is actuated by the cam plate  102 , the plunger  106  causes the heating elements  116  to close on the assay cartridge  20 , heating the fluid (e.g. fluid sample  39 ) within the testing portion  42 . 
     Referring now to  FIG. 48 , the plunger  108  associated with the pinch valve  46  for the assay cartridge  20  is isolated and shown, according to an exemplary embodiment. As the cam plate  102  rotates, the plunger  108  rides along one of the concentric circles  104  on the cam plate  102 . When the device  10  is ready to test the fluid sample  39 , the cam plate  102  rotates until the raised portion  112  of the concentric circle  104  comes in contact with the plunger  108 . The plunger  108  is then forced by the raised portion  112  to pull away from the pinch valve  46 , causing the pinch valve  46  to open, allowing the fluid sample  39  to travel to the testing portion  42 . 
     Referring now to  FIG. 49 , the plungers  108  associated with the pinch valves  47  and  48  for the calibration fluid and air, respectively, are isolated and shown, according to an exemplary embodiment. As the cam plate  102  rotates, the plungers  108  ride along the concentric circles  104 . The plungers  108  are pulled away from the pinch valves  47  and  48  as the cam plate  102  rotates to a predetermined position over the raised portions  112 . The plungers  108  are pulled away from the pinch valves  47  and  48 , causing the pinch valves  47  and  48  to open. Pinch valve  47  opens in order to send calibration fluid to the assay cartridge  20 . Pinch valve  48  opens in order to send air into the assay cartridge  20 . 
     Referring now to  FIG. 50 , an isolated view of a motor assembly  100  and a plunger  108  for actuating an assay cartridge pinch valve  46  are shown, according to an exemplary embodiment. An alternative embodiment of the plunger  108  is also shown in  FIG. 56 . In exemplary embodiments, the rotation of the cam plate  102  is also configured to eject the assay cartridge  20 . The cam plate  102  is configured so that the plungers  108  and  106  are actuated in a sequence that matches the testing sequence of the device  10 . The locking rod  120  locks the cartridge  20  when the cartridge  20  is inserted. At the end of the sequence, the cam plate  102  is configured to loosen the locking rod  120 , releasing the cartridge  20 . A pop up spring  118  at the bottom of the cartridge  20  pops up the cartridge  20 , in exemplary embodiments, and is also used as a recognition mechanism for cartridge  20  insertion. 
     Referring now to  FIG. 51 , a perspective view of a motor assembly  100  for controlling plungers  108  and  106  (i.e. pinch valve actuators) is shown, according to an exemplary embodiment. 
     Referring now to  FIG. 52 , a perspective view of a motor assembly  100  for controlling plungers  108  and  106  (i.e. pinch valve actuators) is shown, according to an exemplary embodiment. 
     Referring now to  FIGS. 53A-C , an L-shaped connector for the calibration cartridge  30  is shown, according to an exemplary embodiment. The L-shaped connector  122  is connected to the bottom of the fluid pack  54  of the calibration cartridge  30 , in exemplary embodiment. The L-shaped connector  122  is configured to deliver calibration fluid from the fluid pack  54 . The L-shaped connector  122  includes a nozzle  124  configured to deliver calibration fluid. The L-shaped connector also includes a fluid pack end  128  that fluidly connects the L-shaped connector  122  to the fluid pack  54 . The L-shaped connector  122  also includes one or more wings  126  extending out from the connector  122 . The wings  126  are intended to allow fluid to travel through the L-shaped connector  122  when the pack is compressed. 
     As utilized herein, the terms “approximately,” “about,” “substantially,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the invention as recited in the appended claims. 
     It should be noted that the term “exemplary” as used herein to describe various embodiments is intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such term is not intended to connote that such embodiments are necessarily extraordinary or superlative examples). 
     The terms “coupled,” “connected,” and the like as used herein mean the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members or the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional intermediate members being attached to one another. 
     The construction and arrangement of the systems and methods for providing the calibration fluid cartridge and in vitro medical diagnostic device as shown in the various exemplary embodiments is illustrative only. Although only a few embodiments of the present inventions have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter disclosed herein. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present invention as defined in the appended claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present inventions. 
     The diagnostic device is generally shown to include a processing circuit including memory. The processing circuit may include a processor implemented as a general purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable electronic processing components. Memory is one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage, etc.) for storing data and/or computer code for completing and/or facilitating the various processes described herein. Memory may be or include non-transient volatile memory or non-volatile memory. Memory may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described herein. Memory may be communicably connected to the processor and includes computer code modules for executing one or more processes described herein.