Abstract:
This invention discloses a detachable test strip good for multiple tests on one strip to reduce the cost of test strip per test, and a test strip with more than two electrodes for the simultaneous measurement of more than one biological data with one drop of blood only.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     a) Field of the Invention  
         [0002]     The present invention generally relates to a new biosensor test strip and, more particularly, to the measurement of blood glucose, uric acid and cholesterol, etc., which will be cost and functional competitive against the current suppliers.  
         [0003]     b) Discussion of the Prior Art  
         [0004]     All the currently available biosensor test strips, whether they are for the measurement of blood glucose, uric acid, or cholesterol, use one strip to perform one test, which are often very expensive for the end users. There are a lot of patients, especially in the developing countries, who are too poor to pay for the DIY tests at home, are in urgent need for a cheaper test strip. Moreover, all current test strips can only give one test result from one test strip, to have different readings of, say, blood glucose, uric acid and cholesterol, requires several individual tests and several blood inoculation which are very painful for the patients. It is therefore the objective of the present invention to come up with a new design of test strip, which can perform more than one test results out of one test strip from one blood inoculation only. It is also another objective of the present invention to design a new test strip with much lower cost for the end users.  
       SUMMARY OF THE INVENTION  
       [0005]     In view of the need for a much cheaper test strip and the need for a test strip capable of performing more than one item of tests with one drop of blood, we therefore design a new detachable test strip, which has multiple test reagents embedded on a single strip. After a good test, the tested section of the strip can be broken off and the other fresh un-tested area with reagents can be kept for further re-use. We also re-design the layout of the conductive electrodes to allow more than one reagents to be embedded on the same designated spot of the test strip for the inoculated blood. Thus, with the application of one drop of blood, several test results can be measured from the data acquired from the specially designed layout of electrodes. 
     
    
     BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0006]     The disposable and detachable test strips of the present invention may be more readily understood by one skilled in the art with reference to the following detailed description taken in conjunction with the accompanying drawings wherein like elements are designated by identical reference numbers throughout the several views and in which:  
         [0007]      FIG. 1  is the schematic view of the detachable test strip with two conductive electrodes, good for three tests, but one reading per test only.  
         [0008]      FIG. 2  is the side view of the detachable test strip showing the composition of the conductive electrodes, which includes a layer of conductive silver and a layer of conductive carbon and on which lies an reagent.  
         [0009]      FIG. 3  illustrates the schematic view of the detachable test strip with three conductive electrodes, good for three tests, but two test readings per test.  
         [0010]      FIG. 4  illustrates the schematic view of the detachable test strips with four conductive electrodes, good for three tests per strip, but two different test readings per test.  
         [0011]      FIG. 5  gives the schematic view of the detachable test strips with four conductive electrodes, good for three tests per strip, but three different test readings per test.  
         [0012]      FIG. 6  gives the schematic view of the detachable test strips with six conductive electrodes, good for three tests per strip, but three different test readings per test.  
         [0013]      FIG. 7A &amp; 7B  indicates another type of detachable test strips for multiple tests, in addition to the detachable device of  FIG. 6 .  
         [0014]      FIGS. 8A, 8B  and  8 C further indicates another type of detachable test strips for multiple tests in addition to the devices of  FIG. 6  and  FIG. 7 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0015]     Referring to the drawing in detail,  FIG. 1  is a schematic view of the detachable test strips with two conductive electrodes, good for performing three tests, but there will be one reading per test only. As a drop of blood is added to the dashed circular area for reagents  36  of the strip  10 , the pre-embedded reagent  36  reacts electrochemically with the blood to produce an electric current, which will be measured through the conductive electrodes to determine the biological readings of interest in the blood. After a test is done with the test, the tested section can be easily broken off from the dashed line  11  which has a pre-cut across the width of the test strip  10  on the opposite side of the test strip  10 , as shown in  FIG. 2 .  FIG. 2  also shows the composition of the electrodes as one layer of conductive silver  21 , on top of which lies a layer of conductive carbon. Reagents  36  are placed on top of the carbon electrode.  FIG. 3  shows the schematic view of the drawings of the detachable test strips with three electrodes, good for performing three tests, but there will be two test readings per test. Reagent  361  is different from reagent  362  to produce two different biological test data with one drop of blood which could cover very well both regents  361  and  362 . The central electrode  201  serves as the ground reference electrode for the neighboring electrodes  202  and  203 .  FIG. 4  further discloses the schematic view of the detachable test with four electrodes, good for three tests per strip but two test reading per test. Electrodes  204  and  205  are used to measure one reaction, just like electrodes  206  and  207 . In order to perform three different measurement on one test piece, there are two different arrangement of electrodes, as shown in  FIG. 5  with four electrodes, and in  FIG. 6  with six electrodes.  FIG. 5  uses the electrode  208  as the ground reference electrodes for electrodes  209 ,  210  and  211 .  FIG. 6  illustrates the schematic view of the detachable test strip with six electrodes, wherein the clechodes  215  and  216  are used to measure the electrochemical reaction of the reagent  363 , while the electrodes  216  and  218  are used to measure the electrochemical reaction of the reagent  365 , and the electrodes  219  and  220  are used to measure the reagent  364 . In  FIG. 6 , although the branch electrode  231  of the electrode  215  crosses over the electrode  216 , it separates from the electrode  217  at the intersection with an electric insulation layer, so is the branch electrode  232  with the electrode  217  and so are the electrodes  231  and  232  with the electrodes  219  an  218  respectively. The area  30  is covered with and insulation material against contamination with foreign objects.  
         [0016]      FIGS. 7A &amp; 7B  further discloses another type of multiple detachable test strips. This is done by attaching a few thin films  50  and  51  of test strips on the base strip  10 . Both thin film of strips,  50  and  51 , and the strip  10  all have conductive electrodes and reagents  36 .  
         [0017]      FIGS. 8A, 8B  and  8 C further give the top, side and exploded views of another type of detachable test strips for multiple tests. Reagents  363 ,  364  and  365  are placed on the test strips  10 ,  61  and  63 , on top of which are coated with two conductive electrodes  240 ,  241  and  242 , respectively, to pick up the electric current from the electrochemical reaction of the reagents with the applying blood. The strips  64 ,  62  and  60  all have three horseshoe cuts  641 ,  621  and  601  to accommodate the reagents for electrochemical reaction, while the strips  61  and  63  serve as the insulation layer for the electrodes  240 ,  241  and  242 , and the strip  65  serves as the protective layer to accommodate the reagents  363 ,  364  and  365  within the horseshoe cuts  641 . The undercuts  101 ,  102  and  103  are the place to apply one blood drop from the side for reaction with three different reagents. The electrodes  240 ,  241  and  242  are insulated from each other by the strips  60 ,  61 ,  62 ,  63 ,  64  and  65 . This whole test strip  10  is designed to the fresh, non-reacted portion.