Abstract:
A system of detecting a blood analyte includes a lateral flow test strip and a test strip holder, the lateral flow test strip located in the test strip holder. The system further includes a meter for receiving the test strip holder.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application No. 62/234,528 filed Sep. 29, 2015, and hereby incorporated by reference to the same extent as though fully disclosed herein. 
     
    
     BACKGROUND 
       [0002]    Various systems exist for point-of-care testing of blood analytes. Many systems for testing for blood analytes include a lateral flow test strip. Such lateral flow test strips typically require a cassette or other type of holder in order to support the test strip and allow for handling by the user without contamination. It is desirable to have a test strip holder that requires minimum material and can interface well with meters and other devices. 
       BRIEF SUMMARY 
       [0003]    In one embodiment, a system of detecting a blood analyte includes a lateral flow test strip and a test strip holder, the lateral flow test strip located in the test strip holder. The system further includes a meter for receiving the test strip holder. Optionally, the system further includes a wicking membrane located in the test strip holder. Alternatively, the test strip holder includes a lid and a base. In one alternative, the lid includes a dosing window, and the wicking membrane is located under the dosing window. In another alternative, the base includes a reading window. Optionally, the base includes a base cavity that receives the lateral flow test strip and the wicking membrane. Alternatively, the base cavity includes a ledge that causes a sample to flow toward the lateral flow test strip from the wicking membrane. In one configuration, the lid is flush with a top of the lateral flow test strip when the lid is engaged with the base, such that excess fluid may not flow on top of the lateral flow test strip. In another configuration, the lid interfaces with the base in a pressure fit arrangement. Optionally, the lid includes wings and snaps into the base. Alternatively, an underside of the lid includes ribs for holding the lateral flow test strip in place. In one alternative, the lid compresses the lateral flow test strip into the base. In another alternative, the meter includes a slot for receiving the lateral flow test strip and test strip holder combination, and the reading window aligns with a sensor of the meter. 
         [0004]    In one embodiment, a test strip assembly includes a lateral flow test strip and a test strip holder, the lateral flow test strip located in the test strip holder. Optionally, the system further includes a wicking membrane located in the test strip holder. Alternatively, the test strip holder includes a lid and a base. Optionally, the lid includes a dosing window, and the wicking membrane is located under the dosing window. In one configuration, the base includes a reading window. In another configuration, the base includes a base cavity that receives the lateral flow test strip and the wicking membrane. Optionally, the base cavity includes a ledge that causes a sample to flow toward the lateral flow test strip from the wicking membrane. Alternatively, the lid is flush with a top of the lateral flow test strip when the lid is engaged with the base, such that excess fluid may not flow on top of the lateral flow test strip. Optionally, the lid interfaces with the base in a pressure fit arrangement. In one alternative, the lid includes wings and snaps into the base. In another alternative, an underside of the lid includes ribs for holding the lateral flow test strip in place. Optionally, the lid compresses the lateral flow test strip into the base. 
         [0005]    In one embodiment, a method of testing for a blood analyte includes providing a test strip assembly, including a lateral flow test strip and a test strip holder, the lateral flow test strip located in the test strip holder. The method further includes introducing a sample to the lateral flow test strip. The method further includes flowing the sample along the lateral flow test strip, producing a colored response to the sample, and measuring the colored response with a meter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIGS. 1 and 2  show one embodiment of a test strip holder including a lateral flow test strip; 
           [0007]      FIG. 3  shows an exploded view of the test strip assembly of  FIG. 1 ; 
           [0008]      FIG. 4  shows a cut-away view of the test strip assembly of  FIG. 1 ; 
           [0009]      FIG. 5  shows one embodiment of the lid of the test strip assembly; 
           [0010]      FIGS. 6 and 7  show one embodiment of the base of the test strip assembly; 
           [0011]      FIG. 8  shows one embodiment of a strip dosed with 15 μL of whole blood; and 
           [0012]      FIG. 9  shows the back side of the strip of  FIG. 8  showing the position of the blue particles when dosed with whole blood. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Certain terminology is used herein for convenience only and is not to be taken as a limitation on the embodiments of the systems and methods for a lateral flow test strip holder. In the drawings, the same reference letters are employed for designating the same elements throughout the several figures. The system presented provides for a test strip holder that can fit with a meter instead of a cassette, which is typically more cost effective, since test strip holders may be smaller and use less material, therefore reducing the cost. 
         [0014]    Embodiments include a novel test strip design where a lateral flow membrane is accommodated. In some embodiments, the design is such that its footprint fits in the optical block of the CardioChek® Plus Analyzer. The strip uses the already existing features of the CardioChek® platform. 
         [0015]    Embodiments of the test strip holder design provide for the opportunity for lateral flow test strips to be used with meters that currently do not receive lateral flow test strips because they are designed to receive cassettes. Specifically, in relation to some embodiments, currently an HbAlc and cotinine assays are offered in a lateral flow format by Polymer Technology Systems, Inc. (PTS). The system includes a lateral flow test strip that is in a cassette. Instead, the lateral flow test strips may be migrated to a test strip which allows it to be received by meters typically designed for vertical flow test strips, such as the CardioChek® series of meters designed by Polymer Technology Systems, Inc. The CardioChek® Plus meter provides for many features that may be desirable to integrate into a meter, including wireless communication, Bluetooth communication, a printer, and access to Health Risk Assessment programs offered by Polymer Technology Systems, Inc. 
         [0016]    Additionally, embodiments of lateral flow test strips in test strip holders provide for reduced sample requirement; therefore, the buffer volume requirement in the sampler is reduced, resulting in additional cost savings. 
         [0017]      FIGS. 1 and 2  show one embodiment of a test strip holder including a lateral flow test strip. The lid and cavity of the test strip holder have been designed to accommodate the lateral flow test strip. The test strip holder and test strip include a dosing window, a wicking membrane, and a lateral flow membrane.  FIG. 1  shows one embodiment of a test strip assembly  100 . The test strip assembly  100  includes a base  110  and a lid  115 . Lid  115  includes a dosing window  120 . A logo section  125  also is included. Logo section  125  also is useful for holding test strip assembly  100 .  FIG. 2  shows a bottom side view of one embodiment of the base  110  of the holder. The base includes a read window  130  for reading a color change with a meter. 
         [0018]      FIG. 3  shows an exploded view of the test strip assembly  100 . The lid  115  and the base  110  are shown. Additionally, the lateral flow membrane  310  and wicking pad  320  are shown. The relation between the dosing window, wicking membrane, and the lateral flow membrane assembly is shown in a cross-sectional image (see  FIG. 3 ). 
         [0019]    As is visible in  FIG. 4 , the wicking pad  320  is aligned with the dosing window  120  of the lid  115 . Additionally, the vertical alignment of the wicking pad  320  and the lateral flow membrane  310  is shown. 
         [0020]      FIG. 5  shows one embodiment of the lid  115  of the test strip assembly  100 . The lid is designed to allow dosing at the distal end of the test strip. The lid snaps into the base  110  with beveled “wings”  510  for ease of manufacturability. The sample port opening, or dosing window  120 , is 0.125 in (3.175 mm) in diameter and with a depth of 0.071 in (1.8 mm) yielding total volume of (0.179 cu mm). The depth of the dosing window  120  can be altered to accommodate a larger volume of sample. The placement of the lid  115  on the test strip assembly  100  can be achieved through a simple pick and place automated mechanism. Another feature is that the bottom of the lid  115  (not shown) has four small ribs or ridges that allow for “holding down” the lateral flow membrane in place and does not allow it to “slip”. Importantly, the cap or lid  115  provides the correct compression to allow efficient wicking of the sample and attain a response in a reasonable amount of time. 
         [0021]      FIGS. 6 and 7  show one embodiment of base  110 . The base  110  length is 1.8 in (45.72) and width is 0.37 in (9.39 mm) which fits the optical block assembly in the current CardioChek® meters, although in alternative embodiments, any meter configuration can be used. The base cavity  610  in which the lateral flow test strip  310  and the wicking membrane  320  will reside is 0.961 inches (24.04 mm) in length and has a width of 0.185 in (4.7 mm). The base has a ledge  710  (see  FIG. 7 ) which allows the flow of fluid in only one direction, which is toward the lateral flow test strip assembly. 
         [0022]    A prototype test was performed with the above embodiment. Prototypes were created, and these prototypes showed that the lateral flow test strips from the PTS cotinine assay were capable of being imported and provide percent reflectance reading. The base was purposely made of transparent plastic to observe and determine the fluid movement in the strip.  FIG. 8  shows one embodiment of a strip dosed with 15 μL of whole blood (no dilution required).  FIG. 9  shows the back side of the strip showing the position of the blue particles when dosed with whole blood. 
         [0023]    While specific embodiments have been described in detail in the foregoing detailed description and illustrated in the accompanying drawings, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure and the broad inventive concepts thereof. It is understood, therefore, that the scope of this disclosure is not limited to the particular examples and implementations disclosed herein but is intended to cover modifications within the spirit and scope thereof as defined by the appended claims and any and all equivalents thereof. Note that, although particular embodiments are shown, features of each may be interchanged between embodiments.