MXPA06008331A - Systems and methods for blood glucose sensing - Google Patents

Abstract

A system for measuring a glucose level in a blood sample includes a test strip and a meter. The test trip includes a sample chamber or other testing zone, a working electrode, a counter electrode, fill-detect electrodes, and an auto-on conductor. A reagent layer is disposed in the testing zone. The auto-on conductor causes the meter to wake up and perform a test strip sequence when the test strip is inserted in the meter. The meter uses the working and counter electrodes to initially detect the blood sample in the sample chamber and uses the fill-detect electrodes to check that the blood sample has mixed with the reagent layer. The meter applies an assay voltage between the working and counter electrodes and measures the resulting current. The meter calculates the glucose level based on the measured current and calibration data saved in memory from a removable data storage device associated with the test strip.

Description

GM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM, - before the expiration of the time limit for amending the ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), claims and to be republished in the event of receipt of European (AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, Fl, amendments FR, GB, GR , HU, IE, IS, IT, LT, LU, MC, NL, PL, PT, RO, SE, SI, SK, TR), OAPI (BF, BJ, CF, CG, Cl, CM, GA, GN, GQ, GW, ML, MR, NE, SN, TD, TG). For two-letter codes and other abbreviations, refer to the "Guid¬ Published: ance Notes on Codes and Abbreviations "appearing at the begin- with intemational search report no ofeach regular issue of the PCT Gazette.

SYSTEMS AND METHODS FOR GLUCOSE MEASUREMENT IN THE BLOOD Field of the Invention The present invention relates to electrochemical sensors and, more particularly, to systems and methods for measuring blood glucose levels electrochemically.

BACKGROUND OF THE INVENTION Many people, such as diabetics, have a need to monitor their blood glucose levels on a daily basis. A variety of systems that allow people to conveniently monitor their blood glucose levels are available. Such systems typically include a test strip to determine the level of glucose in the blood sample. Among the various technologies available to measure blood glucose levels, electrochemical technologies are particularly desirable because only a very small sample of blood may be needed to perform the measurement. In systems based on electrochemistry, the test strip typically includes a sample chamber containing reagents, such as glucose oxidases and a mediator and electrodes. When the user applies a blood sample to the sample chamber, the reagents Ref: 174565 react with glucose, and the meter applies a voltage to the electrodes to cause a reduction oxide reaction. The meter measures the resulting current and calculates the glucose level based on the current. It should be emphasized that accurate measurements of blood glucose levels can be critical to the long-term health of many users. As a result, there is a need for a high level of reliability in the meters and test strips used to measure blood glucose levels. However, as the sample sizes become smaller, the dimensions of the sample chamber and electrodes on the test strip also become smaller. This, again, can cause the test strips to become more sensitive to smaller manufacturing defects and subsequent handling damage. AND? Consequently, there is a need to provide blood glucose measurement systems and methods with characteristics to measure blood glucose levels conveniently and reliably.

Brief Description of the Invention In one main aspect, the present invention provides a test strip for testing a blood sample. The test strip comprises a first substrate, a second substrate defining a test zone, at least four electrodes for measuring at least one electrical characteristic of the blood sample in the test zone, a plurality of electrical contacts electrically connected to the four electrodes, and at least one electrically isolated self-igniting electrical contact of at least four electrodes. The four electrodes include a working electrode, a counter electrode, a detection anode, a filling anode, and a filling detection cathode. In a second main aspect, the present invention provides a method for making a plurality of test strips. According to the method, a plurality of test strip structures are formed into a sheet, and the test strip structures are separated into test strips. Each of the test strip structures includes a spacer that includes a test zone, a plurality of electrodes (including a working electrode, a counter electrode, a fill detection anode, and a fill detection cathode) , a plurality of electrical contacts electrically connected to the electrodes, and at least one self-igniting electrical contact electrically insulated from the plurality of electrodes.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a planar top view of a test strip, in accordance with a first exemplary embodiment of the invention. Figure 2 is a planar top view of the test strip of Figure 1, with a cover, adhesive layer, and reagent layer in section, in accordance with a first exemplary embodiment of the present invention. Figure 3 is a cross-sectional view of a test strip of Figure 1, taken along line 3-3, in accordance with the first exemplary embodiment of the present invention. Figure 4 is a planar top view of the test strip, in accordance with a second exemplary embodiment of the present invention. Figure 5 is a planar top view of the test strip, in accordance with a third exemplary embodiment of the present invention. Figure 6 is a cross-sectional schematic view of the test strip, in accordance with a first alternative embodiment of the present invention. Figure 7 is a cross-sectional schematic view of the test strip, in accordance with a second alternative embodiment of the present invention. Figure 8 is a top schematic view of a configuration of test strip structures, which can be separated into a plurality of test strip of the type shown in Figures 1-3, in accordance with an exemplary embodiment of the present invention. Figure 9 is a planar top view of an intermediate step in the formation of one of the test strip structures of Figure 8, in accordance with an exemplary embodiment of the present invention. Figure 10 is a planar top view of an intermediate step in the formation of one of the test strip structures of Figure 8, in accordance with an exemplary embodiment of the present invention. Figure 11 is a planar top view of an intermediate step in the formation of one of the test strip structures of Figure 8, in accordance with an exemplary embodiment of the present invention. Figure 12 is a planar top view of an intermediate step in the formation of one of the test strip structures of Figure 8, in accordance with an exemplary embodiment of the present invention. Figure 13 is a planar top view of one of the test strip structures of Figure 8, in accordance with an exemplary embodiment of the present invention. Figure 14 is a perspective view of a meter, in accordance with an exemplary embodiment of the present invention. Figure 15 is a perspective view of the meter of Figure 14, with a removable data storage device inserted therein, in accordance with an exemplary embodiment of the present invention. Figure 16 is a perspective view of a strip connector in the meter of Figure 14, in accordance with an exemplary embodiment of the present invention. Figure 17 is a schematic perspective view of the removable data storage device of Figure 15, in accordance with an exemplary embodiment of the present invention. Figure 18 is a flow diagram illustrating the method for using a test strip or revision strip, in accordance with an exemplary embodiment of the present invention. Fig. 19 is a flow chart illustrating a method for using the revision strip, in accordance with an exemplary embodiment of the present invention. Fig. 20 is a flow diagram illustrating a method for using the test strip, in accordance with an exemplary embodiment of the present invention. Figure 21 is a flow chart illustrating a method for using the test strip, in accordance with an exemplary embodiment of the present invention. Figure 22 is a simplified schematic diagram of the electronics of the meter of Figure 14, in accordance with an exemplary embodiment of the present invention.

Fig. 23 is an exemplified schematic diagram of the electrical connections between the meter of Fig. 14 and the electrodes of the test strip of Fig. 1, in accordance with an exemplary embodiment of the present invention. Figure 24 is a simplified schematic diagram of the electrical connections between the meter of Figure 14 and the self-ignition conductor of the test strip of the figure, in accordance with an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In accordance with a preferred embodiment, the system for measuring the glucose level in a blood sample includes a test strip and a meter. The system may also include a removable data storage device associated with a batch of test strip. The removable data storage device stores data for use by the meter, such as calibration coefficients for the test strips of such a lot. The system may also include a review strip that the user can insert into the meter to check that the meter functions properly. The test strip includes a sample chamber or other test area where the blood sample is tested. The blood sample can reach the test zone through an opening at the proximal end of the test strip. The test area can be ventilated through a porous cover or other ventilation structure. The test strip may include a flared section that is narrower at the proximal end, in order to make it easier for the user to locate the opening and apply the blood sample. A working electrode, a counter electrode, a fill detection electrode, and a fill detection anode are positioned so that they are capable of measuring at least one electrical characteristic of the blood sample in the test zone. The reagent layer is placed in the test zone and preferably covers at least the working electrode. The reagent layer may include an enzyme, such as glucose oxidase, and a mediator, such as potassium ferricyanide. The test strip has, near its distal end, a plurality of electrical contacts that are electrically connected to the electrodes by means of conductive lines. The test strip also has a self-igniting lead close to its distal end that can be electrically isolated from the electrodes. The meter can be turned on with batteries and can remain in a low-energy sleep mode when not used in order to save energy. When the test strip is inserted into the meter, the electrical contacts on the test strip come into contact with the corresponding electrical contacts on the meter. In addition, the self-ignition driver links a pair of electrical contacts in the meter, which causes a current to flow through the self-ignition conductor. The current flow through the auto-start wire causes the meter to turn on and enter an active mode. The meter also measures the voltage drop across the self-ignition conductor and identifies the inserted strip as either a test strip or a revision strip based on the voltage drop. If the meter detects a revision strip, it performs a revision strip sequence. If the meter detects a test strip, it detects a test strip sequence. In the test strip sequence, the meter validates the working electrode, counter electrode, and fill detection electrodes when confirming that there is no low impedance path between any of these electrodes. If the electrodes are valid, the meter tells the user that the sample can be applied to the test strip. The meter then applies a drop detection voltage between the working electrodes and counters and detects the blood sample by detecting the current flow between the working and counter electrodes (i.e., a current of flow through the blood sample as it is bridged at the working and counter electrodes). To detect that the proper sample is present in the test zone and that the blood sample has the reagent layer traversed and mixed with the chemical constituents in the reagent layer, the meter applies a fill detection voltage between the detection electrodes of filling and measure any resulting current flow between the filling detection electrodes. If this resulting current reaches a sufficient level within a predetermined period of time, the meter indicates to the user that the proper sample is present and has a mixture with the reagent layer. The meter waits for a period of incubation time after the blood sample is initially detected, to allow the blood sample to react with the reagent layer. Then, during the measurement period, the meter applies a test voltage between the working and counter electrodes and takes one or more measurements of the resulting current flowing between the working and counter electrodes. The test voltage is almost the oxide reduction potential of the chemical in the reactive layer, and the resulting current is related to the level of glucose in the blood sample. The meter calculates the glucose level based on the measurement current and the calibration data that the meter previously discharges from the removable data storage device associated with the test strip and stored in the meter strip. The meter then displays the calculated glucose level to the user. 1. Configuration of the test strip. With reference to Figures 1, 2 and 3 show the test strip 10 in accordance with an exemplary embodiment of the present invention. The test strip 10, preferably takes the form of a generally flat strip extending from the proximal end 12 to the distal end 14. Preferably, the test strip 10 is made of a size for easy handling. For example, the test strip 10 may be about 1 3/8 inches (3.49 cm) long in length (ie, from the proximal end 12 to the distal end 14) and about 5/16 inch ( 0.79 cm) wide. However, the proximal end 12 may be narrower than the distal end 14. In this manner, the test strip 10 may include a flared section 16, in which the full width of the test strip 10 is flared to the extreme next 12, which causes the proximal end 12 to be narrower than the distal end 14. As described in more detail below, the user applies the blood sample to an opening at the proximal end 12 of the test strip 10. Thus, a flared section 16 is provided in the test strip 10, and causes the proximal end 12 to be narrower than the distal end 14, which may assist the user in locating the opening where the blood sample will be applied. and can make it easier for the user to successfully apply the blood sample to the test strip 10. As best shown in Figure 3, the test strip 10 can have a generally layered construction. Working up from the lower layer, the test strip 10 can include a base layer 18 extended along the entire length of the test strip 10. The base layer 18 is preferably composed of an electrically insulated material and has a thickness Sufficient to provide structural support to the test strip 10. For example, the base layer 18 can be polyester which is about 0.014 inches (0.0356 cm) thick. Arranged in the base layer 18 is a conductive pattern 20, The conductive pattern 20 includes a plurality of electrodes disposed in the base layer 18 near the proximal end 12, a plurality of electrical contacts disposed in the base layer 18 near the distal end 14, and a plurality of conductive lines electrically connecting the electrodes to the electrical contacts. In a preferred embodiment, the plurality of electrodes includes a working electrode 22, a counter electrode 24, which may include a first section 25 and a second section 26, a fill detection anode 28, and a fill detection cathode 30. Correspondingly, the electrical contacts may include a working electrode contact 32, a counter electrode contact 34, a fill detection anode contact 36, and a fill detection cathode contact 38. The conductive lines may include a working electrode line 40, which electrically connects the working electrode 22 to the working electrode contact 32, a counter electrode line 42, which electrically connects the counter electrode 24 to the counter electrode contact 34, a detection anode line filling 44 which electrically connects the filling detection anode 28 to the filling detection contact 36, and a cathode line of fillction 46 which electrically connects the fill detection cathode 30 to the fill detection cathode contact 38. In a preferred embodiment, the conductive pattern 20 also includes a self-ignition conductor 48 disposed in the base layer 18 near the distal end 14. A dielectric layer 50 may also be disposed in the base layer 18, so as to cover portions of the conductive pattern 20. Preferably, the dielectric layer 50 is a thin layer (e.g., about 0.0005 inches (0.0127 mm) thick). and is composed of an electrically insulated material such as silicones, acrylics, or mixtures thereof. Preferably, the dielectric layer 50 is also hydrophilic. The dielectric layer 50 can cover portions of the working electrode 22, counter electrode 24, fill detection anode 28, fill detection cathode 30, and conductive lines 40-46, but preferably does not cover the electrical contacts 32-38 or the self-ignition driver 48. For example ,. the dielectric layer 50 can cover substantially all of the base layer 18, and the portions of the conductor pattern 20 therein, from a line just in the vicinity of the contacts 32 and 34 the entire path to the proximal end 12, except for a groove 52 extending from the proximal end 12. In this manner, the slot 52 can define an exposed portion 54 of the working electrode 22, exposed portions 56 and 58 of the sections 25 and 26 of the counter electrode 24, an exposed portion 60 of the anode filling detector 28, and an exposed portion 62 of the filling detection cathode 30. As shown in Figure 2, the slot 52 may have different widths in different sections, which can make exposed portions 60 and 62 of the detection electrodes of filling 28 and 30 wider than the exposed portions 54, 56 and 58 of the working electrode 22 and the counter electrode sections 25 and 26. The next layer on the test strip 10 can be a dielectric spacer layer 64 disposed in the dielectric layer 50. The dielectric spacer layer 64 is composed of an electrically insulated material, such as polyester. The dielectric spacer layer 64 may have a length and width similar to that of the dielectric layer 50, but may be substantially thicker, for example about 0.005 inches (0.127 mm) thick. In addition, the spacer 64 may include a slot 66 that is substantially aligned with the slot 52. In this manner, the slot 66 may extend from the proximal end 68, aligned with the proximal end 12, behind the distal end 70, such that the exposed portions 54-62 of the working electrode 22, counter electrode 24, fill detection anode 28, and fill sensing cathode 30 are located in the groove 66. A cover 72, having a proximal end 74 and an end distal 76 may be attached to the dielectric spacing layer 64 by means of an adhesive layer 78. The cover 72 is composed of an electrically insulated material, such as polyester, and may have a thickness of about 0.004 inches (0.102 mm). Preferably, the cover 72 is transparent. Adhesive layer 78 may include a polyacrylic or other adhesive and have a thickness of about 0.0005 inches (0.0127 mm). The adhesive layer 78 may consist of a first section 80 and a second section 82 disposed in the spacer 64 on opposite sides of the slot 66. A partition 84 in the adhesive layer 78 between the sections 80 and 82 extends from the distal end 70. from the slot 66 to an opening 86. The cover 72 can be arranged in the adhesive layer 78 in such a way that its proximal end 74 is aligned with the proximal end 12 and its distal end 76 is aligned with the opening 86. In this way, the cover 72 covers the slot 66 and the partition 84. The slot 66, together with the base layer 18 the cover 72, defends a sample chamber 88 on the test strip 10 to receive a blood sample for measurement. The proximal end 68 of the slot 66 defines a first opening in the sample chamber 88, through which blood sample is introduced into sample chamber 88. At the distal end 70 of the slot 66, the division 84 defines a second opening than in the sample chamber 88, to ventilate the sample chamber 88 as the sample entering the sample chamber 88. The slot 66 is made in a dimension such that the blood sample applied to this proximal end 68 is configured in and held in sample chamber 88 by capillary action, with division 84 venting sample chamber 88 through opening 86, as the blood sample enters. However, the slot 66 is made in a dimension such that the blood sample entering the sample chamber 88 by capillary action is about 1 microliter or less. For example, the slot 66 may have a length (i.e., from the proximal end 68 to the distal end 70) of about .140 inches (3.56 mm), a width of about .060 inches (1.52 mm), and a height (which can be defined substantially by the thickness of the spacer and electrical layer 64) of about .005 inches (0.127 mm). However, other dimensions may be used. • A reagent layer 90 is disposed in the sample chamber 88. Preferably, the reagent layer 90 covers at least the exposed portion 54 of the working electrode 22. More preferably, the reagent layer 90 also at least touches the exposed portions 56 and 58 of the counter electrode 24. The reagent layer 90 includes chemical constituents to allow the glucose level in the blood sample to be determined electrochemically. In this manner, the reagent layer 90 can include a specific enzyme for glucose, such as glucose oxidase, and a mediator, such as potassium ferricyanide. Reagent layer 90 may also include other components, such as buffer materials (e.g., potassium phosphate), polymeric binders (e.g., hydropropyl methylcellulose, sodium alginate, microcrystalline cellulose, polyethylene oxide, hydroxyethylcellulose, and / or polyvinyl alcohol), and surfactants (for example, Triton X-100 or Surfynol 485). With these chemical constituents, the reagent layer 90 reacts with glucose in the blood sample in the following manner. Glucose oxidase initiates a reaction that oxidizes glucose to gluconic acid and reduces ferricinanide to ferrocyanide. When an appropriate voltage is applied to the working electrode 22, in relation to the counter electrode 24, the ferrocyanide is oxidized to ferricyanide, thereby generating a current that is related to the concentration of glucose in the blood sample. As best shown in Figure 3, the multi-layered configuration in the test strip 10 may result in the test strip 10 having different thicknesses in different sections. In particular, between the layers above the base layer 18, the majority of the thickness of the test strip 10 can be from the thickness of the spacer 64. In this manner, the end of the spacer 64 that is closest to the distal end 14 can defining a projection 92 on the test strip 10. The projection 92 can define a thin section 94 of the test strip 10, extended between the projection 92 and the distal end 14, and a thick section 96, which extends between the projection 92 and the proximal end 12. The elements of the test strip 10 used to electrically connect to the meter, especially, the electrical contacts 32-38 and self-igniting conductor 48, all can be located in the thin section 94. Accordingly, the connector in the meter can be made of a size such that it is capable of receiving the thin section 94 but not the thick section 96, as described in more detail below. This can beneficially target the user to insert the correct end, that is, the distal end 14 into the thin section 94, and can prevent the user from inserting the wrong end, that is, the proximal end 12 into the thick section 96, in the meter Although Figures 1-3 illustrate a preferred configuration of the test strip 10, other configurations may be used. For example, in the configuration shown in Figures 1-3, the counter electrode 24 is made of two sections, a first section 25 which is at the proximal end of the working electrode 22 and a second section 26 which is on the distal side of the working electrode 22. On the other hand, the combined area of the exposed portions 56 and 58 of the counter electrode 24 is preferably larger than the area of the exposed portion 54 of the working electrode 22. In this configuration, the counter electrode 24 surrounds effectively the working electrode 22, which beneficially protects the working electrode 22 electrically. In other configurations, however, the counter electrode 24 may have only one section, such as the first section 25. They may also be used in different configurations of the fill detection electrodes 28 and 30. In the configuration shown in FIGS. 3, the filling detection electrodes 28 and 30 are in a side-by-side configuration. Alternatively, the fill sensing electrodes 28 and 30 may be in a sequential configuration, therefore, as the sample flows through the sample chamber 88 toward the distal end 70, the sample contacts one of the first. Filling detection electrodes (either at anode or cathode) and then puts in contact the other filling detection electrode. In addition, through the exposed portions 60 and 62 of the filling detection electrodes 28 and 30 are wider than the exposed portions 54, 56 and 58 of the working electrode 22 and the counter electrode sections 25 and 26 in the embodiment shown in figure 2, it can have the same width or a narrower one in other modalities. Although they are configurations that are related to one another, it is preferable for the filling detection electrodes 28 and 30 to be located on the distal side of the reagent layer 90. In this way, as the sample flows through the sample chamber 88 towards the distal end 70, the sample will pass through the reagent layer 90 at the time of reaching the filling detection electrodes 28 and 30. This configuration beneficially allows the filling stop electrodes 28 and 30 to detect not only the sufficient blood sample. which is presented in the sample chamber 88, but also detects the blood sample which is sufficiently mixed with the chemical constituents of the reagent layer 90. In this way, if the reagent layer 90 covers the working electrode 22, as it is preferred, then it is preferable to locate the filling detection electrodes 28 and 30 on the distal side of the working electrode 22, as in the configuration sample in the Figure 1-3. However, other configurations may be used. Different configurations of the sample chamber in the test strip are also possible. For example, the figure 4, shows an alternative modality, test strip 100, in which the sample chamber is ventilated without the use of a partition in an adhesive layer. In the test strip 100, the spacer 64 includes a ventilation slot 102 that defines the sample chamber. The slot 102 includes a wide section 104, which may have a relatively uniform width, a flared section 106, which may have a rounded shape, and a narrow section 108, which may also have a rounded shape. The exposed portions of the working and counter electrodes may be located in the wide section 104 and the proximal end of the flared section 106, and the exposed portions of the filling detection electrodes may be located at the distal end of the flared section 106. The cover 72 is attached to the spacer 64 (eg, using an adhesive) so as to cover the groove 102 except for the distal end of the narrow section 108. In this manner, the narrow section 108 can vent the sample chamber defined by the slot 102. In addition, the rounded shape of the flared section 106 may allow the sample to flow through the sample chamber more smoothly and uniformly. A ventilated slot does not need to have a rounded shape, however. For example, Figure 5 shows another alternative embodiment, test strip 110, in which the sample chamber is also ventilated without the use of a split in an adhesive layer. In the test strip 110, the spacer 64 includes a vented groove 102 defining the sample chamber. The slot 102 includes a wide section 114, which may have a relatively uniform width, and a narrow section 116, which may also have a relatively uniform width. The exposed portions of the working, counter, and fill detection electrodes can all be located in the wide section 114, with the exposed portions of the fill detection electrodes located at the distal end of the wide section 114. The cover 72 is attached to the spacer 64 (eg, using an adhesive) so as to cover the slot 112, except for the distal end of the narrow section 116. In this way, the narrow section 116 can vent the sample chamber defined by the slot 112.

In the above approaches, to ventilate the sample chamber or test zone, that is, use a partition in an adhesive layer or leave a portion of the slot in the spacer uncovered, the cover 72 may be provided as a sheet of material substantially non-porous For example, the 9971 hydrophilic polyester film 3M ™, a polyester film with a hydrophilic cover on the side that is in contact with the blood sample, may be used as the cover 72. However, in an alternative method, a porous cover it can be arranged over the test area. In this alternative method, the test zone can be ventilated through the porous cover, so that no other structure for ventilating the test zone may be needed.

The porous cover can be provided as a mesh. For example, Figure 6 shows a cross-sectional schematic view of a test strip with a mesh 118 placed over the test zone 119 which is defined by a slot in the spacer 64. The slot in the spacer 64 also defines an opening in the proximal end of the test strip, through which the blood sample can be traced on. test zone 119 by capillary action. The mesh 118 may be attached to the spacer 64, for example, by an adhesive. In exemplary embodiments, the mesh 118 has pore sizes in the range of 18 to 105 microns and has a thickness in the range of 60 to 90 microns.

Preferably, the mesh 118 is hydrophilic. For example, the mesh 118 may be made of polyester, polyamide, or polypropylene in such a manner that it is immersed in a detergent solution, such as dioctyl sulfosuccinate. The use of the 118 mesh can simplify certain aspects of the manufacture of the test strips by eliminating any need for other ventilation structures. In particular, as the blood sample enters the test zone 119, the test zone 119 can be ventilated through the 118 mesh. However, in some cases, the 118 mesh may allow the blood sample, as well as the air, to flow through this. In this way, the user may be able to apply the blood sample through the mesh 118 instead of through the opening at the proximal end of the test strip as intended. Applying the blood sample in this way could result in an incorrect glucose reading. In addition, the mesh 118 may not necessarily seal the sides of the test zone 119, as shown in Figure 6, thereby allowing blood to move through the 118 mesh. In another approach, a perforated sheet may be used. like the porous cover. For example, Figure 7 shows a cross-sectional view of a test strip with a perforated sheet 120 placed over the test area 121 which is defined by a slot in the spacer 64. The groove in the spacer 64 also defines an opening in the proximal end of the test strip, through which the blood sample can be traced in the test zone 121 by capillary action. The perforated sheet 120 includes a plurality of holes 122 formed therethrough, for example, in a regular configuration. In an exemplary embodiment, holes 122 are each about 0.005 inches (0.127 mm) in diameter and spaced about 0.020 inches (0.508 mm) from the center-center. The perforated sheet 120 can be formed by starting with a non-perforated sheet of material, such as hydrophilic polyester film 9971 from 3M ™, and then forming the holes 122 therein, for example, by laser drilling or mechanical puncture. Preferably, the perforated sheet 120 is hydrophilic on the side that is in contact with the blood sample. • When the blood sample enters the test zone 121, the test zone 121 can be ventilated through the holes 122 in the perforated sheet 120. In this way, using the perforated sheet 120 can, just as using the 118 mesh, eliminate the need for other ventilation structures. However, the perforated sheet 120 may provide certain advantages over the mesh 118. For example, the perforated sheet 120 may seal the sides of the test zone 121, thereby reducing the possibility of the blood sample leaking. Further, by using the perforated sheet 120 instead of the mesh 118, it can be made more difficult to apply the blood sample in the wrong way, that is, through the porous cover instead of the opening at the proximal end of the test strip. Other configurations of the test strip, for example, with other electrode configurations and / or test zone, may also be used. 2. Method for manufacturing test strips Figures 8 through 13 illustrate an exemplary method for manufacturing test strips. Although these figures show the steps for manufacturing the test strip 10, as shown in Figures 1-3, it will be understood that similar steps can be used to manufacture the test strips having other configurations, such as the test strips shown in any of Figures 4 to 7. With reference to Figure 8, a plurality of the test strips 10 can be produced in mass by forming an integrated structure 124 that includes a plurality of test strip structures 126 all in one sheet. The test strip structures 126 may be configured in a configuration that includes a plurality of rows 128 (e.g., six rows), with each row 128 including a plurality of test strip structures 126 (e.g., fifty strip structures). test in each row). The plurality of test strip 10 can then be formed by separating the test strip structures 126 from one another. In a preferred separation process, each row 128 of the test strip structures 126 is first removed from the integrated structure 124. This removal process can provide some of the outer shape of the test strip 10. For example, the shape Flared section of the flared sections 16 of the test strips 10 can be formed in this removal process. Next, a cutting process can be used to separate the test strip structures 126 in each row 128 into individual test strips 10. Figures 9 through 13 show only a test strip structure (either partially or completely fabricated) in order to illustrate several steps in a preferred method for forming the test strip structures 126. In this preferred method, the test strip structures 126 in an integrated structure 120 are all formed into a sheet of material that serves as the base layer 18 in the finished test strips 10. The other components in the finished test strips 10 are then built on layer by layer in the upper part of the base layer 18 to form the test strip structures 126. In each of the Figures 9 through 13, the outer shape of the test strip 10 that is formed in the general manufacturing process is shown as the dotted line. As shown in Figure 9, the manufacturing process can be started by forming, for each test strip structure, a first conductive pattern 130 in the base layer 18. The first conductive pattern 130 can include electrical contacts 32-38, - conductive lines 40-42, and a self-igniting conductor 48. The first conductive pattern 130 can be formed by an on-screen printing of a first conductive ink in a base layer 18. The first conductive ink can be provided as a viscous liquid that includes particles of a conductive material, such as metallic silver. For example, a first preferred conductive ink has a composition of about 30-60% by weight of metallic silver, about 5-10% by weight of dark oil, about 30-60% by weight of dipropylene glycol monomethyl ether, and other components, and it's available from EI DuPont de Nemours & Co. , Wilmington, DeJLaware, as "Membrane Switch Composition 5524". As shown in Figure 10, a second conductive pattern 132 can then be formed in the base layer 18. The second conductive pattern 132 can include the working electrode 22, the first section 25 and the second section 26 of the counter electrode 24, the filling detection anode 28, and filling detection cathode 30. The second conductive pattern 132 can be formed by printing a second conductive ink on the screen on the base layer 18. The second conductive ink can be provided as a viscous liquid including particles of a conductive material, such as graphite. The second conductive ink may have a composition different from that of the first conductive ink. In particular, the second conductive ink is preferable substantially free of materials such as. silver, which may interfere with the chemistry of the 90 reagent layer. second preferred conductive ink has a composition of about 10-20% by weight of graphite, about 5-10% by weight of dark oil, more than 60% by weight of ethylene glycol diacetate, and about 5-10% by weight of polymer, and is available from EI DuPónt de Nemours &; Co., Wilmington, Delaware, as ?? 100735-III. "As shown in Figure 11, the dielectric layer 50 can then be formed in a base layer 18 so as to cover the portions of the first conductor pattern 130 and the second conductor pattern 132. As shown in Figure 11, the dielectric layer 50 may extend beyond the outer line of the finished test strip 10 so as to cover the multiple test strip structures that are formed in the base layer 18. Also as shown in Figure 11, the dielectric layer 50 may include a slot 134 defining the exposed portions 54, 56, 58, 60, and 62 of the working electrode 22, first electrode section counter 25, second electrode section counter 26, portion of the fill detector anode 28, and portion of the cathode of filling detection 30. The slot 52 in the test strip 10 corresponds to the part of the slot 134 that is held in the test strip 10 after the test strip structures are separated into strips of p In this regard, the slot 134 may include a wide section 135 which allows the portions of the filling detection electrodes 28 and 30 to be exposed by the layer 50 to be wider than the portions of the working electrode 22 and the counter electrode 24 is left exposed by layer 50. In a preferred method, dielectric layer 50 is hydrophilic and is applied by screen printing a dielectric material. The preferred dielectric material comprises a mixture of silicon and acrylic compounds, such as the "Membrane Switch Composition 5018" available from E.I. DuPont de Nemours & Co. , Wilmington, Delaware. Other materials may be used, however. In the next step, the dielectric spacing layer 64 can be applied to the dielectric layer 50, as illustrated in Figure 12. The spacer 64 can be applied to the dielectric layer 50 in a variety of different ways. In an exemplary method, the spacer 64 is provided as a sheet large enough and appropriately to cover multiple test strip structures. In this approach, the underside of the spacer 64 can be covered with an adhesive to facilitate bonding to the dielectric layer 50 and the base layer 18. The portions of the upper surface of the spacer 64 can also be covered with an adhesive in order to provide a adhesive layer 78 on each of the test strips 10. Several slots may be covered in or removed from the spacer 64 to form it before the spacer layer 64 is applied to the dielectric layer 50. For example, as shown in Figure 12 , the spacer 64 may have a slot 136 for each test structure and a slot 138 that extends over the multiple test strip structures. In addition, the spacer 64 may include adhesive sections 140 and 142, with a partition 84 therebetween, for each test strip structure formed. The spacer 64 is then placed on the base layer 18 as shown in Figure 12, and processed in foil for the base layer 18 in the dielectric layer 50. When the spacer 64 is properly placed in the base layer 18, the portions of exposed electrode 54-62 are accessible through the slot 136. In this manner, the slot 66 in the test strip 10 corresponds to that which is part of the slot 136 which is held in the test slot 10 after which The test strip structures are separated into test strips. Similarly, slot 138 in spacer 64 leads contacts 32-38 and self-igniting conductor 48 to be exposed after lamination. Alternatively, the spacer 64 may be applied in other ways. For example, the spacer 64 can be injection molded into the base layer 18 and dielectric 50. The spacer 64 can also be constructed in the dielectric layer 50 by successive layers of screen printing of a dielectric material at an appropriate thickness, for example, around of 0.005 inches (0.127 mm). A preferred dielectric material comprises a mixture of silicon and acrylic compounds, such as the "Membrane Switch Composition 5018" available from E.I. DuPont de Nemours &; Co., Wilmington, Delaware. Other materials may be used, however. The reagent layer 90 can then be applied to each test strip structure. In a preferred method, the reagent layer 90 is applied by micropipetting an aqueous composition to an exposed portion 54 of the working electrode 22 and allowed to dry to form the reagent layer 90. A preferred aqueous composition has a pH of about 6 and contains 2% by weight of polyvinyl alcohol, 0.1 M potassium phosphate, 0.05% by weight of Triton X-100, 0.15 M potassium ferricyanide, 0.7% hydroxyethylcellulose (such as NATROSOL®), and about 2500 glucose units oxidase per mL. Alternatively, other methods, such as screen printing, can be used to apply the composition used to form the reagent layer 90.

A transparent cover 72 can then be attached to the adhesive layer 78. As shown in Figure 13, the cover 72 (shown as transparent) can be large enough to cover the multiple test strip structures 122. The bonded cover 72 can complete the formation of the plurality of test strip structures 122. The plurality of strip structures of Test 122 can then be separated from one another to form plurality of test strips 10, as described above. 3. The meter and the removable data storage device To measure the level of glucose in a blood sample, a test strip (e.g., test strip 10, test strip 100, or test strip 110) is preferably used with the meter 200, as shown in Figures 14 and 15.

Preferably, the meter 200 has a size and shape that allows it to be conveniently held in the user's hand while the user is measuring glucose. The meter 200 may include a front side 202, a front side 204, a left side 206, a right side 208, an upper side 210, and a bottom side 212. The front side 202 may include a screen 214, such as a liquid crystal display (LCD). The bottom side 212 may include a strip connector 216 in which the test strip is inserted to conduct a measurement. The left side 206 of the meter 200 may include a data connector 218 in which the removable data storage device 220 may be inserted, as described in more detail below. The upper side 210 may include one or more user controls 222, such as buttons, with which the user can control the meter 200. The right side 208 may include a serial connector (not shown). Figure 16 shows a preferred embodiment of the strip connector 216 in more detail. The strip connector 216 includes a channel 230 with a flared opening 231 for receiving the test strip. The tabs 232 and 234 hang on the right and left sides, respectively, of the channel 230 at a predetermined height. This predetermined height 232 and 234 is set to allow the distal end 14 (in section 94), but not the proximal end 12 (in the thick section 96), to be inserted into the strip connector 216. In this way, the user can avoid improperly inserting the test strip into the strip connector 216. The electrical contacts 236 and 238 are arranged in the channel 230 behind, the tabs 232 and 234, and the electrical contacts 240-246 are arranged in the channel 230 behind the electrical contacts 236 and 238. When the distal end 14 of the test strip is properly inserted into the strip connector 216, the electrical contacts 236-246 contact the electrical contacts 32-38 and the auto-start conductor 48. by electrically contacting the test strip to the meter 200. In particular, the electrical contacts 236 and 238 contact the electrical contacts 32 and 34, respectively, for electrical contacting. e the working electrode 22 and the counter electrode 24 to the meter 200. The electrical contacts 240 and 242 contact the electrical contacts 36 and 38, respectively, to detect the electrically filling of the electrodes 28 and 30 to the meter 200. Finally , electrical contacts 244 and 246 electrically connect the self-igniting lead 48 to the meter 200. The meter 200 can use the data from the removable data storage device 220 to calculate the glucose levels in the blood samples measured by the meter 200. Specifically , the data storage device 220 may be associated with a batch of test strips and may store one or more parameters that the meter 200 may use for such a batch. For example, the data storage device 220 may store one or more calibration parameters that the meter 200 can use to calculate the glucose level of a current measurement averaged. The calibration parameters may include temperature corrections. The data storage device 220 may also store other information - related to batch of the test strips and the meter, such as a code that identifies the mark of the test strips, a code that identifies the model of the meter to be used, and an expiration date for the batch of the test strips. The data storage device 220 may also store other information used by the meter 200, such as the duration of the fill counter and the incubation counter, the voltages to be used for the drop level voltage at 1, fill, and level Test excitation 2, one or more parameters related to the number of current measurements to be made, and one or more parameters that specify how the meter should average current measurements, as described in more detail below. The data storage device 220 may also store one or more checksums of the stored data or portions of the stored data. In a preferred method, before a given batch of test strips is used with the meter 200, the removable data storage device 220 associated with the given batch is first inserted into the data connector 218. The meter 200 can then loading the relevant data from the data storage device 220 into an internal memory when the test strip is inserted into the strip connector 216. With the relevant data stored in its internal memory, the meter 200 does not need the storage device of the user. 220 data to measure glucose levels using the test strips in a given batch. In this way, the removable data storage device 220 can be removed from the meter 200 and can be used to encode the meters. If the data storage device 220 is kept in the meter 200, the meter 200 may no longer access but instead use the data stored in its internal memory. With reference to Figure 17, the removable data storage device 220 may include a memory chip 250 mounted on a circuit board 252, which, again, is mounted to the carrier 254. The memory chip 250 stores the data in a predetermined format Preferably, the memory chip 250 includes a non-volatile memory, so that it retains the stored data when it is turned off. For example, the memory chip 250 can be a programmable, memory-only, erasable, electronic memory chip (EEPROM). Such EEPROM chips can typically be written many times (for example, one million writing cycles, or more) so that they are not spent during the life cycle of use.

The memory chip 250 can be electrically connected to a plurality of electrical contacts in a circuit board 252. These electrical contacts can include a voltage supply contact 256, a ground contact 258, a data input / output contact 260, and a clock contact 262. In this way, when the appropriate voltage is applied to the voltage supply 256, relative to the ground contact 258, the data can be read synchronously from or written to the memory chip 250 using the input contact. / data output 260 and clock contact 262. As described in more detail below, the ground contact may be as long as the other electrical contacts 256, 260 and 262, for greater reliability. The carrier 254 may be made of a material such as plastic and may include a distal end 264 and a proximal end 266. The distal end 264 is intended to be inserted into the data connector 218. The proximal end 266 may include a flange 268 for allowing the fingers of the user to squeeze the removable data storage device 220 either to insert or remove from the data connector 218. The carrier 254 may include an opening 270 through which the electrical contacts 256-262 are accessible. In this way, when the data storage device 220 is properly inserted into the data connector 218, the electrical contacts 256-262 on the circuit board 252 contact the corresponding electrical contacts 272-278 (shown in Figure 14). ), respectively, in the data connector 218. In this way, the meter 200 can become electrical connected to the memory chip 250 to read the data stored therein. The carrier 254 and the data connector 218 can "provided with keys" so that the removable data storage device 220 can be inserted into the connector 218 only in one orientation. For example, him < carrier 254 may include a wedge-shaped corner 282 and connector 218 may include a wedge-shaped opening 284 to receive the wedge-shaped corner 282. As a result, the data storage device 220 can be placed in the data connector 218 only when it is oriented so that the wedge-shaped corner 282 is received in the shape opening. wedge 284. For the sake of benefit, this lase placement may indicate to the user the proper insertion orientation and may prevent damage that could be caused by improper insertion. Another feature of the removable data storage device 220 that can increase its reliability is the longer length of the ground contact 258. Specifically, the circuit board 252 is mounted to the carrier 254 so that the ground contact 258- extends closer of the distal end 264 (this is the end inserted into the data connector 218) than the other contacts 256, 260, and 262. As a result, the ground contact 258 is the first electrical contact in the circuit board 252 that makes contact electrical with the meter 200 when the data storage device 220 is inserted into the data connector 218 and the last electrical contact in breaking the electrical contact with the meter 200 when the data storage device 220 is removed. This prevents the memory chip 250 from being turned on in an unintended operation mode that may not be reliable, for example, the voltage supply of the meter 200 is applied to the memory chip 250 through the voltage supply contact 256 without the memory chip 250 is also connected to the earth through the ground contact 258. 4. The use of the test strip with the meter In order to save energy, the meter 200 preferably is in a low-energy "sleep" mode most of the time. However, the meter 200 can be "activated" and enter an active mode when certain situations arise. For example, by actuating one or more of the user's controls 222 may cause the meter 200 to be activated, as may be attempted to use the serial port 416 for the data transfer. Preferably, inserting either a test strip (e.g., test strip 10, test strip 100, or test strip 110) or a review strip on the meter 200 also wakes up. The meter 200 can then determine whether the inserted strip is a test strip or a revision strip. The flow chart in Figure 18 illustrates this process. First, the meter 200 is in a low energy sleep mode, as indicated by step 300. Then, either a test strip or review strip is inserted into the meter 200, as indicated by step 302. The insertion causes the self-ignition conductor of the strip (e.g., self-ignition conductor 48 on test strip 10) to strike self-ignition contacts 244 and 246 on meter 200. As a result, a self-start current begins to flow through the self-ignition contacts 244 and 246 and through the self-ignition driver. This self-ignition current causes the meter 200 to wake up and enter in an active mode, as indicated by the step 304. In this active mode, the meter 200 measures the voltage drop across the self-ignition conductor, as indicated by step 306. In a preferred method, the resistance of the self-ignition leads in the test strips is significantly different than in the revision strips. In this way, the meter 200 can determine whether the strip inserted in this is a test strip or a revision strip based on the voltage drop of the auto-ignition. For example, the self-ignition leads on the test strips may have a substantially lower resistance than on the revision strips. Accordingly, the meter 200 can compare the high-voltage voltage drop to a predetermined threshold value, as indicated by step 308. If the self-start voltage drop is less than the predetermined threshold value, then the meter 200 identifies the strip as the test strip and performs a test strip sequence, as indicated by step 310. On the other hand, if the self-ignition voltage drop is greater than the predetermined threshold value, then the meter 200 identifies the strip as a revision strip and perform a revision strip sequence, as indicated by step 312. The flow chart of figure 19 illustrates the preferred test strip sequence. The test strip may have electrical contacts near its distal end (in addition to the self-ignition conductor) which are similar to the electrical contacts 32-38 on the test strip, except that the electrical contacts on the inspection strip can contact resistors, with predetermined resistance, instead of the current electrodes . In this way, when a revision strip is inserted into the meter 200, the electrical contacts 236 and 238 may have the contacts of "working electrode" and "counter electrode" in the review strip which are currently connected by means of contact. of the first resistor in the revision strip. Similarly, electrical contacts 240 and 242 can contact the "fill detection" contacts on the revision strip are currently connected by means of a second resistor on the revision strip. As summarized in Figure 19, the meter 200 can perform the revision strip sequence by measuring the currents through the first and second resistors in the revision strip to determine if the measured values fall within the accepted ranges. If the measured current values do not fall within the accepted ranges, then there may be a. problem with the meter 200. In this way, the meter 200 can first measure the current 'through the work electrode contacts and counter 236 and 238 to obtain a current value measured through the first resistor, as indicated by step 314. The meter 200 then determines if this measured current value is within the acceptable range, as indicated by step 316. If the measured current value is not within the acceptable range, then the meter 200 indicates a state of fails, as indicated by step 318.

To indicate the failure status, meter 200 may display a message or icon on screen 214 and / or provide some other indication of failure discernable by the user. If the current measured through the first resistor is within the acceptable range, then the meter 200 can also measure the current through the fill detection electrode contacts 240 and 242 to obtain a measurable current value through the second resistor. , as indicated by step 320. Then, the meter 200 determines whether this measured current value is within an acceptable range, as indicated by step 322. If the current value due is not within the acceptable range, then the meter 200 indicates a fault state, as indicated by step 324. If the average current value is within the acceptable range, the meter 200 may indicate an operational state. For example, the meter 200 may display an "OK" icon on the display 214. As noted above, if the meter 200 detects a test strip, then the meter 200 performs a test strip sequence. As a first phase of the test strip sequence, the meter 200 can validate the working electrodes, counter, and fill detector by determining if the impedances therebetween are sufficiently high. This process is illustrated in the flow chart of Figure 20. As indicated by step 328, the meter 200 can apply a first predetermined validation voltage, for example, the "Drop Level 1" voltage between the electrodes of work and counter 22 and 24 and measure any resulting current flow through the working electrode 22 .. The first validation voltage should result in little or no current, because it should not have a low impedance path between the electrode work 22 and the counter electrode 24. In this way, the meter 200 can check if the resulting current is below the maximum allowable value, as indicated, by step 330. If the resulting current is above the maximum value, then the meter may indicate a fault status, as indicated by step 332. Otherwise, meter 200 may proceed with the test strip sequence and apply a second predetermined validation voltage adored, for example, the "fill" voltage, through the filling detection electrodes 28 and 30 and measuring any resulting current flow through the fill detection anode 28, as indicated by step 334. The meter 200 can store this current measurement so that it can be used in later measurements, as described in more detail below. This second validation voltage should result in little or no current, because it should not have any low impedance path between any electrodes. However, electronic components, such as amplifiers, in the meter 200 can produce small equivalent currents that are measured in step 334. The meter 200 can be checked that the current measurements of step 334 are below the maximum allowable value, as indicated by step 336. If the current measurement is above the maximum value, then the meter 200 may indicate a fault status, as indicated by step 338. Otherwise, the meter 200 may indicate that the sample Blood can be applied on the test strip. For example, the meter 200 may display a message or icon on the screen 214 and / or provide some other indication discernible by the user. The meter 200 can perform the measurement of step 334 while performing the measurement of step 328. In this way, meter 200 can apply the "Drop Level 1" voltage between the work electrodes and counter 22 and 24, measuring any resulting current through work electrode 22, while at the same time applying the "Fill" voltage between the fill detection electrodes 28 and 30 and measuring any resulting current through the fill detection anode 28 If the electrodes are validated, the meter 200 can then proceed with the mixed process in the flow chart of Figure 21. To detect when the user applies the blood sample, the meter 200 applies the voltage "Drop Level 1" to through the work electrode 22 and the counter electrode 24 and measure any resultant current flow between those electrodes, as indicated by step 342. Preferably, the voltage of "Drop Level 1" is less than the oxide reduction potential of the chemical used in the reagent layer 90. In step 344, the user applies the blood sample to the test strip. More particularly, the user can apply the blood samples to the opening of the sample chamber 88 at the proximal end 12, as shown in Figure 3. As noted above, the sample chamber 88 is sized to trace the blood sample. in this by capillary action. As the blood sample moves in the sample chamber 88, it will eventually join the working electrode 22 and the counter electrode 24, thereby providing an electrically conductive path between them. In this way, the meter 200 determines that the blood sample is present in the sample chamber 88 when the resulting current reaches a predetermined threshold value or series of threshold values with a change in the overall positive magnitude, as indicated by the step 346. When the meter 200 detects the blood sample in this manner, the meter 200 disconnects the work electrodes and counter 22 and 24, placing them in a state of high impedance relative to the filling detection electrodes 28 and 30 and the meter 200 initiates a fill counter and an incubation counter, as indicated by step 348. Before the meter 200 places the work electrodes counter 22 and 24 in the high impedance state, the meter 200 can first place them to discharge the stored charges. The filling counter sets a time limit for the blood sample to pass through the reagent layer 90 and reach the filling detection electrodes 28 and 30. The incubation counter sets a delayed period to allow the blood sample to reach the blood layer. reagent 90. Once the meter 200 starts the fill counter run, the meter 200 applies a voltage, the "filling" voltage, between the filling detection electrodes 28 and 30 and measures the. resulting current flowing between these electrodes, as indicated by step 350. The meter 200 can subtract from this measured current the current measurement of step 334 to obtain a set current. As indicated by step 352, the meter 200 - checks if the. current (or adjusted current) reaches a predetermined threshold value or a series of thresholds with a change in the positive quantity generated before the fill counter elapses. Prably, the current thresholds are set so that the meter 200 can determine whether the sample has reached the filling detection electrodes 28 and 30 and if the sample has been mixed with the chemical constituents in the reagent layer 90. If the current (or adjusted current) does not reach the required value, then there may be some problem with the test strip. For example, it may be blocked in the sample chamber 88. There may be an inadequate number of samples. There may be no reagent layer, or the chemical constituents of the reagent layer may have failed to mix with the blood sample. Any of these problems can make the glucose measurement unreliable. Accordingly, if the filling counter passes without a sufficient current (or current, adjusted) through the filling detection electrodes 28 and 30, the meter 200 may indicate a fault state, as indicated by step 354. The meter 200 can indicate this failure status by requiring an error message or icon on the screen 214 and / or by providing some other indication that can be determined by the user. The duration of the filling counter can, for example, be in the range of 2 to 6 seconds. If, however, the meter 200 detects a sufficient current (q adjusted current) through the filling detection electrodes 28 and 30 before the fill counter elapses, then the meter 200 can proceed with the measurement process of glucose. As indicated by step 356, the meter 200 can provide an indication to the user that the 200 meter has detected the proper sample mixed with the chemical constituents of the reagent layer 5. For example, the meter 200 can emit a sound , displaying a message or icon on the screen 214, or providing some other indication discernible by the user. Prably, the meter 200 also disconnects the filling detection electrodes 28 and 30, attaching them 1. 0 to a state of high impedance relative to the working electrode 22 and the counter electrode 24. The meter 200 can seat the filling detection electrodes 28 and 30 before placing them in the high impedance state in order to discharge the stored charges . The meter 200 is Then wait for the incubation counter to pass, as indicated by step 358, in order to allow sufficient time for the blood sample to react with the reagent layer 90. The incubation counter can, for example, take around from 2 seconds 0 to around 10 seconds to elapse, depending on the implementation. In a preferred embodiment, the incubation counter lasts about 5 seconds. When the incubation counter passes, the meter 200 applies the voltage of "Test Excitation Level 2" to the working electrode 22 and the counter electrode 24 and inhibits the resulting current flow between these electrodes, as indicated by the step 360. Preferably, the meter 200 measures the resulting current at a fixed sampling rate through a measurement period, to obtain a plurality of current measurements. The measurement period can last from around 5 seconds around 15 seconds, depending on the implementation. In a preferred embodiment, the measurement period lasts at least about 5 seconds. The meter 200 then determines the glucose level in the blood sample of the current measurements, as indicated by step 362. In a preferred method, the meter 200 can average the current measurements to obtain a. average current value at a predetermined point of time during the measurement period. The meter 200 can then use the calibration data obtained from the removable data storage device 220 and store it in its internal memory to calculate the glucose level of the average current value. The meter 200 can also take a temperature reading and use the temperature reading to correct the glucose level measured by temperature dependence. In addition, the meter 200 can check the validity of current measurements by checking that the measured current reduces over time, as expected.

For example, in a preferred embodiment, the meter 200 can take a predetermined number of current measurements (m? ...?) In a time interval of 0.1 seconds. The predetermined number, M, can, for example, be in the range from 50 to 150, and can be a specified parameter - in the removable data storage device 220. The meter can then average each current measurement n to provide a plurality of data points (d! ... dN). In this way, if n equals 3, the meter can calculate dx by averaging mi, m2, and m3 and calculate d2 by averaging m2, m3, and m. The averaged parameter, n can be a parameter specified in the removable data storage device 220. Once the data points can be selected as the central point for another average level, in which the meter averages the data points together It goes around and includes the center point to provide a meter reading, X. In this way, if d2 is selected as the center point, then the meter can average dx, d2 and d3 together to calculate the meter reading X. The removable data storage device 220 can store a parameter that specifies which of the data points is used as the central point for calculating the meter reading X. The meter 200 then calculates the glucose level Y, of the meter reader X, and one or more calibration parameters, which can be specified in the removable data storage device '220. For example, in an exemplary embodiment, the meter 200 may use three calibration parameters a, b, and c, to calculate Y, using the expression a + bX + cX2. Alternatively, different expressions, which may include different terms and / or different numbers of. Calibration parameters can be used to calculate Y. For example, in another exemplary embodiment, Y can be calculated using the expression a + bX + cX2 + dlX. In some cases, the data storage device 220 may specify that the expression to be used to calculate "Y", in addition to which calibration parameters are used. The glucose level, Y, calculated in this way may not be the correct temperature, however. To correct the temperature, the 200 meter can apply one or more temperature correction parameters, which can be specified in the removable data storage device 220. For example, in a preferred embodiment, the corrected glucose level of temperature can be calculated of the expression A + BT + CRT + DY, where A, B, C and D are the temperature correction parameters and T is a measured temperature. The calibration parameters A, B, C, and D can be specified in the removable data storage device 220. In other embodiments, the temperature correction can use only a single parameter, S, which can be specified in the storage device. removable data 220. For example, the correct temperature glucose level can be calculated from the expression Y / [(1 + S (T-21)] If the current measurements appear valid, then the meter 200 displays the level of glucose, typically as a number, on screen 214, as indicated by step 364. Meter 200 may also store the measured glucose level, with a timestamp, in its internal memory.

. Measurement Electronics Figure 22 shows, in simplified form, the electronic components of the meter 200, in accordance with a preferred embodiment. The meter 200 can - include a microcontroller 400 that controls the operation of the meter 200 in accordance with the schedule, which can be provided as software and / or firmware (microprograms). The microcontroller 400 may include a processor 402, a memory 404, which may include a read-only memory (ROM) and / or a random access memory (RAM), a screen driver 406 and one or more input / output ports (1/0) output 408. The memory 404 may be stored a plurality of language instructions. machines comprising the programming to control the operation of the meter 200. The memory 404 can also store data. The processor 402 executes the language instructions of the machine, which can be stored in the memory 404 or other 5. components, to control the microcontroller 400 and, thus, the meter 200. In particular, the processor 402 can execute the language instructions of the stored machine so that the meter 200 performs the functions summarized in the flow diagrams of Figures 18-21 as 0 is described above. The microcontroller 400 'may also include other components under the control of the processor 402. For example, the microcontroller 400 may include a display driver 406 to assist the processor 402 in controlling the display 214. In a preferred embodiment, the display 214 is a LCD and the 406 screen driver is an LCD driver / controller. The microcontroller may also include ports 1/0 408, which allow the processor 402 to communicate with the external components to the microcontroller 400. The microcontroller 400 may also include one or more counters 410. The processor 402 may use the counters 410 to measure the filling time period, incubation time period, and other periods of time described above. The microcontroller 400 can be provided as an integrated circuit, such as the HD64F3802H, available from Hitachi. The microcontroller 400 is preferably connected to the components that provide a user interface. The components that make the user interface of the meter 200 include the display 214 a sound signal 412 and user controls 222. The microcontroller 400 can be displayed and / or graphics on the display 214. The microcontroller can cause the sound signal 412 sound, such as to indicate that the suitable sample (mixed with the chemical of the reagent layer 90) has reached the filling detection electrodes 18 and 30, as described above. The microcontroller 400 may also be connected to other components, such as one or more light-emitting diodes (LEDs), to provide indications discernible by the user, which may be visible, audible, or touchable. The microcontroller 400 can receive user input from the user controls 222. In a preferred embodiment, the user controls 222 consist of a plurality of discrete switches. However, user controls 222 can also include a touch screen or other components in which a user can provide an input to the meter 200. The microcontroller 400 can access one or more memories external to it, such as. EEPROM 414. In a preferred embodiment, the microcontroller 400 stores the measured glucose levels, and the times and data in which the glucose measurements are presented, in EEPROM 414. By using the user controls 222, the user may also be able cause the microcontroller 400 to display one or more of the glucose measurements stored in EEPROM 414 on the display 214. The microcontroller 400 may also be connected to a serial port 416, through which the user can access the glucose measurements stored in EEPROM 414. The microcontroller 400 can use a transmission line, "TX", to transmit signals to serial port 416 and can use a receiver line, "RX", to receive signals from serial port 416. EEPROM 414 can also store data from removable data storage devices 220. In this aspect, Figure 22 shows how the electrical contacts 272-278 of the data connector 216 are connected inside the meter 200. The contact 272 is connected to a power source, which can be through the microcontroller 400. In this way, the microcontroller 400 can "control the power", the removable data storage device with power 220, through the contact 272, only when necessary, for example, when downloading data from the removable data storage device 220. The contact 274 gets in touch with the earth. The contacts 276 and 278 are connected to the data input / output and the clock output, respectively, of the microcontroller 400. In this way, the microcontroller 400 can download the data from the data storage device 220, when connected to the connector data 216, and store the data in EEPROM 414. In a preferred embodiment, the meter 200 also includes a data acquisition system (DAS) 420 which is digitally interfaced with the microcontroller 400. The DAS 420 can be provided as a circuit integrated, such as the MAX1414, available from Maxim Integrated Products, Sunnyvale, California. The DAS 420 includes one or more analog digital converters (DAC) that generate analog voltages in response to the digital data of the microcontroller 400. In particular, DAS 420 includes the terminals "Voutl" and "FBI", which DAS 420 uses to apply voltages analogs generated by the first DAC to the working electrode 22, when the test strip is inserted into the strip connector 216. Similarly, DAS 420 includes the terminals "Vout2" and "FB2", which DAS 420 uses to apply analogous voltages generated for a second DAC to the fill detection anode 28, when the test strip is inserted into the strip connector 216. The one or more DACs in DAS 420 generate analog voltages based on the digital signals provided by the microcontroller 400. this way, the voltages generated by one or more DACs can be selected by the processor 402. The DAS 420 also includes one or more analog-to-digital converters (ADC) with which DAS 420 is capable of measuring signals an Alogas. As described in more detail below, DAS 420 can use one or more ADCs connected to the terminals "Voutl" and "Vout2" to measure currents of the working electrode 22 and the counter electrode 24, respectively, when the test strip is insert into strip connector 216. DAS 420 may also include one or more terminals through which ADCs can measure analog signals, such as the "Analog Inl" and "Analog In2" terminals shown in Figure 22. DAS 420 You can use the "Analog Inl" terminal to measure the voltage across the auto-start wire on the test strip or the test strip that connects to the strip connector 216. The "Analog In2" terminal can be connected to the thermal resistance, RT1, to allow DAS 420 to measure the temperature. In particular, DAS 420 can supply a reference voltage Vref, through a voltage divider that includes the thermal resistance RT1, and another resistance Rd. DAS 420 can use the "Analog In2" terminal to measure the voltage across the thermal resistance RT1. DAS 420 transfers the digital values obtained from one or more ADCs to the microcontroller 400, by means of the digital interface between these components.

Preferably, DAS 420 has at least two modes of operation, a "sleep" or low energy mode and an "active" or run mode. In active mode, 'DAS 420 has full functionality. In sleep mode, DAS 420 has reduced functionality but consumes much less current. For example, although DAS 420 can consume 1 mA or more in active mode, DAS 420 can consume only microamps in sleep mode. As shown in Figure 22, DAS 420 can include the "Activate", "Activate2", and "Activate3" entries. When the appropriate signals are asserted at any of these "Activate" terminals, DAS 420 can activate from sleep mode, enter active mode, and activate at the remainder of meter 200, as described in more detail below. In a preferred embodiment, the "Activate" inputs are low activity inputs that are placed internally to the supply voltage, Vcc. As described in more detail below, inserting the self-ignition lead in either the test strip or the revision strip in the strip connector 216 causes the "Activate" input to go down and, therefore, cause DAS 420 enters the active mode. In addition, the "Activate2" input can be connected to one or more of the user controls 222. In this way, user activation of at least some of the user controls 222 causes DAS 420 to enter the active mode. Finally, the "Activate3" input can be connected to the serial port 416, for example, by means of the received line, "RX". In this way, it is attempted to use the serial port 416 for the data transfer can activate DAS 420 and therefore the meter 200. As shown in Figure 22, DAS 420 includes several terminals that are connected to the microcontroller 400. DAS 420 includes one or more "I / O Data" terminals, through which the microcontroller 400 can write digital data to and read digital data from the DAS 420. DAS 420 also includes a "Clock terminal" that receives a signal clock of the microcontroller 400 to coordinate the transfer of data to and from the terminals "I / O data". DAS 420 also includes a "Clock Out" terminal through which DAS 420 can supply a clock signal 'which directs the microcontroller 400. DAS 420 can generate this clock signal when using a 422 crystal. DAS 420 can also generate a real-time clock (RTC) using the crystal 422. DAS 420 may also include other terminals through which DAS 420 can enter other types of digital signals to the microcontroller 400. For example, DAS 420 may include a "Restart" terminal to through which DAS 420 can output the signal to reset the 400 microcontroller. DAS 420 can also include one or more "Out" switches, which DAS 420 can use to provide interrupted signals to the microcontroller 400. DAS 420 can also include one or more "Data Reading" entries that DAS 420 can use for the signal microcontroller 400 that DAS 420 has acquired data, such as from an analog to digital conversion, which e is easy to transfer to the microcontroller 400. As shown in FIG. 22, the meter 200 may include a power source, such as one or more batteries 424. The voltage regulator 426 may provide a regulated supply voltage VCc from the voltage supply by the batteries 424. The supplied voltage VCc, can then turn on the other components of the meter 200. In a preferred embodiment, the voltage regulator 426 is a step-by-step CD-to-CD voltage converter. The voltage regulator 426 may be provided as an integrated circuit and other components, such as an inductor, capacitors and resistors. The integrated circuit may, for example, be a MAX1724 available from Maxim Integrated Products, Sunnyvale, California. Preferably, the voltage regulator 426 has a stop mode, in which it only provides an unregulated output voltage. DAS 420 may include a "stop" terminal through which DAS 420 can control the voltage regulator 426. In particular, when DAS 420 enters sleep mode DAS 420 can impose a low level signal on its "stop" terminal which causes the voltage regulator 426 to enter the stop mode. When DAS 420 enters the active mode, a high level signal is imposed on its "stop" terminal, which allows the voltage regulator 426 to operate normally. Figure 22 also shows how the electrical contacts 236-246 of the strip connector 216 are connected to the meter 200. The contacts 236 and 238 which are electrically connected to the working electrode 22 and the working electrode 24, respectively, when the strip Test is inserted into the strip connector 216, connected as follows. The contact 236, for the working electrode 22, is connected to the "FBI" terminal of DAS 420 and is connected by means of the resistor RFI to the "Voutl" terminal of DAS 420. The contact 238, for the counter electrode 24, it is connected to the switch 428. The switch 428 allows the contact 238 (and, therefore, the counter electrode 24) to be connected to the ground or left in a high impedance state. The switch 428 can be controlled digitally by the microcontroller 400, as shown in Figure 22. When the counter electrode 24 is connected to the ground, DAS 420 can use the terminals "Voutl" and "FBI" to apply voltages to the working electrode. 22 (in relation to the counter electrode 24) and measure the current through the working electrode 22. The contacts 240 and 242, which are electrically connected to the filling detection anode 28 and the filling detection cathode 30, respectively, when The test strip is inserted into the strip connector 216, connected as follows. The contact 240, for the filling detection anode 28, is connected to the terminal "FB2" of DAS 420 and is connected by means of the resistor, RF2, to the terminal "Vout2" of DAS 420. The contact 242, for the filling detection cathode 30, is connected to the switch 430. The switch 430 allows the contact 242 (and, therefore, the filling detection cathode 30) to be connected to the ground or left in a high state impedance. The switch 430 can be controlled digitally by the microcontroller 400, as shown in Fig. 2. With the fill detection cathode 30 connected to the ground, DAS 420 can use the terminals "Vout2" and "FBI" to apply voltages to the anode fill detection 28 (relative to the fill detection cathode 30) and to measure the current through the fill detection anode 28. The switches 428 and 430 can be single throw / single pole (SPST) switches, and they can be provided as an integrated circuit, such as the MAX4641, available from Maxim Integrated Products, Sunnyvale, California. However, other configurations for switches 428 and 430 may be used. The contacts 244 and 246 which are electrically connected to the self-ignition conductor when the test strip or revision strip is inserted into the strip connector 216, are connected as follows. Contact 246 contacts the ground or other reference potential. The contact 244 is connected to the terminals "Analog Inl" and "Activate" of DAS 420 and to the microcontroller 400. As described in more detail • below, the presence of the drivers of the self-ignition driver drives the "Activate" terminal downwards , therefore activating DAS 420 and causing it to enter an active mode. DAS 420 uses the "analog Inl" terminal to measure the voltage through the self-ignition conductor. By virtue of this connection to the contact 244, the microcontroller 400 is able to determine whether the self-ignition conductor is present, and in this way, whether either a test strip or revision strip is connected to the strip connector 216. The figure 23 shows in more detail the functional aspects of the connections between the meter 200 and the electrodes 22, 24, 28 and 30, when the test strip is inserted into the strip connector 216. As shown in Figure 23, DAS 420 functionally includes an amplifier 440 for the working electrode 22 and an amplifier 442 for the filling detection anode 28. More particularly, the output of the amplifier 440 is connected to the working electrode 22, by means of the "Voutl" terminal. "and the resistor, RF1, and the inverted input of the amplifier 440 is connected to the working electrode 22, by means of the" FBI "terminal.

Similarly, the output of the amplifier 442 is connected to the fill detection anode 28, by means of the "Vout2" terminal and the resistor RF2, and the inverted input of the amplifier 442 is connected to the filling detection anode 28 by means of the terminal "FB2". To generate selected analog voltages to apply the work electrode 22 and the fill detection electrode 28, DAS 420 includes a first DAC 444 and a second DAC 446, respectively. DAC 444 is connected to the non-inverted input of amplifier 440, and DAC 446 is connected to the non-inverted input of amplifier 442. In this way, amplifier 440 applies a voltage of the "Voutl" terminal, such that the voltage at the working electrode 22, as sensitized at the inverted input of the amplifier 440, is essentially equal to the voltage generated by DAC 444. Similarly, the amplifier 442 applies the voltage to the "Vout2" terminal, such that the electrode Fill detection 28, as sensitized at the inverted input of amplifier 442, is essentially equal to the voltage generated by DAC 446. To measure the currents through the working electrode 22 and the fill detection anode 28, DAS 420 includes a ADC 448 and multiplexers (MUXes) 450 and 452. The MUXex 450 and 452 are able to select the ADC 448 inputs from between the terminals "Voutl", "FBI", "Vout2" and "FB2". DAS 420 may also include one or more dampers and / or amplifiers (not shown) between ADC 448 and MUXes 450-. and 452. To measure the current through the working electrode 22, MUXes 450 and 452 connect DC448 to the terminals "Voutl" and "FBI" to measure the voltage across the resistor RF1, which is proportional to the current through of the working electrode 22. To measure the current through the filling detection electrode 28, MUXes 450 and 452 connect ADC 448 to the "Vout2" _ and "FB2" terminals to measure the voltage across the resistor RF2, which is proportional to the current through the fill detection anode 28. As noted above, the meter 200 preferably includes switches 428 and 430 which can be used to carry the counter electrode 24 and the fill detection cathode 30, respectively, to a high impedance state. It is also preferable for the meter 200 to be able to bring the working electrode 22 and the fill detection anode 28 to a state of high impedance. In a preferred embodiment, this can be achieved by DAS 420 which is capable of carrying the terminals "Voutl", "FBI", "Vout2" and "FB2" in high impedance states. Accordingly, DAS 420 can effectively include switches 454, 456, 458 and 460 as shown in Figure 23. However, switches 428, 430 and 454-460 can be SPST switches, as shown in Figure 23, others types of switches, such as single-pole double-throw (SPDT) switches can be used, and switches can be configured in other ways, in order to provide the meter 200 with the ability to select a pair of electrodes (either the pair working and counter or electrode detection torque filling) and bring the other pair of electrodes in a state of high impedance. For example, the pair of SPDT switches can be used, with selected SPDT switch so that the working electrode 22 and fill detection 28 are connected to DAS 420 and the other SPDT switch selected so that the counter electrode 24 and the Cathode sensing filling are connected to the ground. In other chaos, the meter 200 may not be configured to carry all the electrodes in a high impedance state. For example, in some embodiments, the meter 200 may not include the switch 428, which results in the counter electrode 24 always being connected to the ground when the test strip is inserted into the strip connector 216. Figure 24 shows in FIG. Further detail the functional aspects of the connections between the meter 200 and the self-ignition conductor when either a test strip or review strip is inserted into the strip connector 216. As shown in Figure 24, the self-ignition conductor provides an effective resistance, Rauo / between the contacts 244 and 246 of the strip connector 216. Inside the meter 200, the contact 244 contacts the voltage source, VCC through an effective resistance, Rs. For example, the "Activate" terminal of DAS 420, to which the contact 244 is connected, can be removed internally for Vcc / through an effective resistance Rs. Accordingly, when either a test strip or revision strip is inserted into the strip connector 216, in such a way that the self-ignition conductor contacts the contacts 244 and 246, a current flows through the self-ignition resistor and a voltage drop that develops between contacts 244 and 246. The magnitude of this self-ignition voltage drop depends on the magnitudes of R to and Rs. Preferably, Rauto is chosen sufficiently low for the test strips and strips of revision, relative to Rs, such that the self-start voltage is less than the logical low voltage (which may be around 0.8 volts) used in the meter 200. It is also preferable for Rauto to be substantially different in the strips of test and review strips, so that the meter 200 can determine the type of strip of the self-ignition voltage drop. For example, if Rs is around 500kO, then Rauto can be less than about 20 O in the test strip and can be about 20 kO in the review strip. In this way, the microcontroller 400 can determine whether either a test strip or a revision strip is inserted into the 216% strip connector by sensing a low logic voltage at contact 244. The DAS 420 also senses the voltage drop. of self-ignition and use it to activate the meter 200 and to determine the type of strip, that is, if the test strip or review strip has been inserted in the strip connector 216. In the case of the test strip, DAS 420 can also confirm that the test strip has been properly inserted in the strip connector 216. The DAS 420 can include the ignition logic 462, which senses the voltage in the "Activate" terminal, by means of a buffer and / or one or more buffers and / or amplifiers, such as buffer 464. DAS 420 also includes ADC 448, which can measure the voltage in the "Analog Inl" terminal, by means of one or more buffers and / or amplifiers, such as memory intermediate 466. Although not shown in Figure 24, MUX 450 and 452 can be connected between buffer 466 and ADC 448. When no strip is present at strip connector 216, contact 244 (and thus, the terminal "Activarl") is at a high voltage, or near VCc- However, when either a test strip or review strip is inserted into the strip connector 216, the self-ignition conductor conducts the voltage at the terminal "Activate" goes down, as described above. The ignition logic 462 perceives the voltage in the "Activate" terminal down and, in response, initiates the activation sequence to bring DAS 420 into an active mode. As part of this activated sequence, the logic of. Ignition 462 can cause DAS 420 to impose a signal on its shutdown terminal on the voltage regulator 426. The ignition logic 462 can also cause DAS 420 to generate signals to activate the microcontroller 400. For example, the activation logic 462 can cause DAS 420 to impose a clock signal through its clock terminal, a stop signal through its stop terminal and an interrupt signal through its interrupt terminal to activate the microcontroller 400. Although not shown in Figure 24, the activation logic 462 can also perceive the voltages at the activated 1 and activated 2 terminals and, in response to a voltage at one of these terminals lowering it, can initiate an activation sequence similar to that which is describes above. When DAS 420 enters the active mode, also determines the type of strip inserted in the strip connector 216. In particular, ADC 448 measures the voltage in the analog terminal Inl. DAS 420 then reports the measured voltage for the microcontroller 400. Based on this information, the microcontroller 400 then initiates either a test strip sequence or a revision strip sequence, as described above. Through any sequence, the microcontroller 400 may periodically check the voltage at the contact 244 to ensure that the strip is still inserted into the strip connector 216. Alternatively, an interruption may notify the microcontroller 400 of an increase in the voltage in the the contact 244 caused by the removal of the strip. In this way, the self-ignition voltage drop developed through the self-ignition driver performs several functions in the meter 200. First, the self-start voltage causes the meter 200 to wake from a sleep mode to an active mode. Second, the meter 200 determines the type of strip of the magnitude of the auto-ignition voltage. Third, the self-ignition voltage leads the meter 200 to know which strip is still inserted in the strip connector 216, as the meter 200 proceeds with either the test strip sequence or the revision strip. 6. Conclusion Preferred embodiments of the present invention have been described above. Those skilled in the art will understand, however, that changes and modifications can be made to these embodiments without departing from the actual scope and spirit of the invention, which is defined by the claims. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (33)

1. Claims Having described the invention as above, the content of the following claims is claimed as property. 1. A test strip for measuring glucose in a blood sample, the test strip characterized in that it comprises: a base layer, the base layer sheet having a proximal end and a distal end, the proximal end is narrower than the distal end; at least four electrodes arranged in the base layer, the at least four electrodes including a working electrode, a counter electrode, a fill detection anode, and a fill detection cathode; a plurality of electrical contacts arranged in the base layer, the plurality of electrical contacts includes a working electrode contact, a counter electrode contact, a fill detection anode contact, and a fill detection cathode contact; a plurality of conductive lines disposed in the base layer, the plurality of electrically connected conductive lines from the working electrode to the contact of the working electrode, the counter electrode to the counter electrode contact, the anode detecting filling to the anode detection contact filling, cathode filling detection to cathode contact filling detection; a self-ignition conductor arranged in the base layer; a first dielectric layer disposed in the base layer, the first dielectric layer converts portions of the working electrode and counter electrode, to define an exposed working electrode portion and an exposed counter electrode portion; a second dielectric layer disposed in the base layer, the second dielectric layer having a groove, the working electrode, the counter electrode, the filling detection anode, and the filling detection cathode is disposed in the groove, the slot having a proximal end and a distal end, the proximal end of the slot is aligned with the proximal end of the base layer; 'a reagent layer disposed in the groove, the reagent layer includes glucose oxidase and a mediator; and a porous cover disposed in the second dielectric layer, wherein the groove defines a test area for testing the blood sample, the groove is dimensioned to draw the blood sample in through the proximal end of the groove by the action capillary.
2. 2. The test strip according to claim 1, characterized in that the porous cover comprises a mesh.
3. 3. The test strip according to claim 1, characterized in that the porous cover comprises a perforated sheet.
4. 4. The test strip according to claim 1, characterized in that the counter electrode 'includes a first section and a second section, the working electrode is arranged in the base layer between the first section and the second section.
5. 5. The test strip according to claim 1, characterized in that the at least four electrodes are formed by a first conductive ink printed on the base layer.
6. 6. The test strip according to claim 5, characterized in that the first conductive ink contains graphite.
7. 7. The test strip according to claim 6, characterized in that the electrical contacts, the conductive lines, and the self-ignition conductor are formed by a second conductive ink printed on the base layer.
8. 8. The test strip according to claim 7, characterized in that the second conductive ink contains silver.
9. 9. The test strip according to claim 1, characterized in that the test strip has a thick section and a thin section, the thick section includes the proximal end, the thin section includes the distal end, the electrical contacts and the self-ignition conductor they are located in the thin section.
10. 10. The test strip according to claim 1, characterized in that the reagent layer covers the portion of the exposed working electrode.
11. 11. A test strip for testing a blood sample, the test strip characterized in that it comprises: a first substrate; a second substrate, the second substrate defines a test zone for testing the blood sample; . at least four electrodes, arranged on the first substrate, for measuring at least one electrical characteristic of the blood sample in the test zone, the at least four electrodes include a working electrode, a counter electrode, a filling detection anode , and a filtering detection cathode; a plurality of electrical contacts arranged on the first substrate and electrically connected to at least four electrodes; and at least one self-ignition electrical contact disposed on the first substrate and electrically isolated from at least four electrodes.
12. 12. The test strip according to claim 11, further characterized in that it comprises: a reactive layer disposed in the test zone.
13. 13. The test strip according to claim 11, further characterized in that it comprises: a cover arranged on the test area.
14. 14. The test strip according to claim 13, characterized in that the cover is a porous cover.
15. 15. The test strip according to claim 14, characterized in that the porous cover comprises a mesh.
16. 16. The test strip according to claim 14, characterized in that the porous cover comprises a perforated sheet.
17. 17. The test strip according to claim 11, characterized in that the test strip has a proximal end and a distal end, wherein the second substrate defines an opening at the proximal end for receiving the blood sample.
18. 18. The test strip according to claim 17, characterized in that the proximal end is narrower than the distal end.
19. 19. The test strip according to claim 17, characterized in that the test strip has a thick section and a thin section / the thick section includes the proximal end, the thin section includes the distal end.
20. 20. The test strip according to claim 19, characterized in that the plurality of electrical contacts and at least one self-ignition electrical contact are located in the thin section.
21. 21. A method for making a plurality of test strips, the method characterized in that it comprises: forming a plurality of test strip structures in an insulating sheet, wherein each test strip structure is formed by: (a) forming a first conductive pattern in the insulating sheet, the first conductive pattern includes at least four electrodes, the at least four electrodes include a working electrode, a counter electrode, a fill detection anode, and a fill detection cathode; (b) formation of a second conductive pattern in the insulating sheet, the second conductive pattern includes a plurality of electrode contacts for the at least four electrodes, a plurality of electrically conductive lines connected to the at least four electrodes to the plurality of contacts of electrode, and a self-ignition driver; (c) application of a first dielectric layer on portions of the working electrode and counter electrode, to define an exposed working electrode portion and an exposed counter electrode portion; (d) application of a second dielectric layer to the first dielectric layer, the second dielectric layer defines a groove, the working electrode, the counter electrode, the filling detection anode, and the filling detection cathode is disposed in the groove; (e) formation of a reagent layer in the groove, the reagent layer includes glucose oxidase and a mediator; and (f) linking a porous cover to the second dielectric layer; and separating the plurality of test strip structures into the plurality of test strips, each of the test strips having a proximal end and a distal end, with the slot * extended to the proximal end, the proximal end being narrower than the distal end.
22. 22. The method according to claim 21, characterized in that the porous cover comprises a mesh.
23. 23. The method according to claim 21, characterized in that the porous cover comprises a perforated sheet.
24. 24. The method according to claim 21, characterized in that the formation of a first conductive pattern in the insulating sheet comprises: printing a first conductive ink on the insulating sheet, the first conductive ink contains graphite.
25. 25. The method according to claim 24, characterized in that the formation of a second conductive pattern in the insulating sheet comprises: printing a second conductive ink on the insulating sheet, the second conductive ink contains silver.
26. 26. A method for making a plurality of test strips, the method characterized in that it comprises: forming a plurality of test strip structures in a sheet, each test strip structure includes: (a) a spacer defining a test zone; (b) a plurality of electrodes formed in the sheet, including a working electrode, a counter electrode, a fill detection anode, and a fill detection cathode; - (c) a plurality of electrical contacts, formed in the sheet and electrically connected to the plurality of electrodes; and (d) at least one self-ignition electrical contact, formed in the sheet and electrically isolated from the plurality of electrodes; and separating the test strip structures in the plurality of test strips.
27. 27. The method according to claim 26, characterized in that each of the structures of the test strip further comprises: a cover arranged on the test area.
28. 28. The method according to claim 26, characterized in that the cover is a porous cover.
29. 29. The method according to claim 28, characterized in that the porous cover comprises a mesh.
30. 30. The method according to claim 28, characterized in that the porous cover comprises a perforated sheet.
31. 31. The method according to claim 26, characterized in that each of the structures of the test strip includes a reagent layer disposed in the test zone.
32. 32. The method according to claim 26, characterized in that the separation of the test strip structures in the plurality of test strips comprises: perforating the plurality of test strip structures to form a plurality of test strip structures in the form conical, each of the conical test strip structures has a conical section.
33. 33. The method according to claim 30, characterized in that the separation of the structures of the test strip in the plurality of test strips further comprises: -_: grooving the plurality of test strip structures in a conical shape in the plurality of test strips.