Blood sugar concentration calculation method and sensor

Abstract

A blood sugar concentration calculation method and a sensor. A first excitation signal and a second excitation signal are input for a first working electrode, when the first excitation signal for the first working electrode is completed, the first working electrode is in an open-circuit state, and then an excitation signal sequence is input for a second working electrode; when the excitation signal sequence for the second working electrode is completed, the second working electrode is in the open-circuit state, and then the second excitation signal for the first working electrode is enabled; the output current of current acquisition points of the first excitation signal, the second excitation signal and the excitation signal sequence is collected at regular intervals; and the blood sugar concentration is obtained by means of a calculation formula. The blood sugar concentration calculation method considers the mutual influence relationship between various interference factors related to the blood sugar concentration, and further improves the accuracy and accuracy of testing the blood sugar concentration in a biological sample.

Description

A blood glucose concentration calculation method and sensor

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 28, 2023, with application number "202311854788.8" and invention name "A blood glucose concentration calculation method and sensor", the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of blood glucose concentration detection, and in particular, to a method for calculating blood glucose concentration and a sensor for testing analytes in biological samples. Background Art

[0003] Traditional biosensors achieve test selectivity by catalyzing a single reaction with biomolecules, based on a two-step chain reaction. In the second reaction (the comb flow reaction), the reduced state of the mediator diffuses to the electrode and is then oxidized, generating a corresponding current signal. The catalytic process for the analyte can be described in three steps:

[0004] (1) Analyte + enzyme oxidation state = biochemical reaction product + enzyme reduction state

[0005] (2) Mediator oxidized state + enzyme reduced state = mediator reduced state + enzyme oxidized state

[0006] (3) Mediator reduced state (electrode) = mediator oxidized state + e-

[0007] The enzyme biomolecules in the glucose detection sensor system catalyze the oxidation of glucose molecules in the blood. The reaction between the added mediator and the enzyme converts the enzyme from the reduced state back to the oxidized state, thus playing a combing role. Glucose enzymes can be oxidases or dehydrogenases. Since oxidases are oxidized by the dissolved oxygen in the blood sample, while dehydrogenases are not, there is no "dissolved oxygen effect". Dehydrogenases have been the first choice of enzymes in biosensors for the past two decades. The catalytic enzymes of other analytes may be oxidases or dehydrogenases, and the biosensor principles are basically the same. However, during the test, although the enzyme-catalyzed reaction is basically single, there may be other interfering substances that can be oxidized in the blood sample. These interfering substances may undergo oxidation reactions, resulting in interference signals. Generally speaking, the higher the standard potential of the mediator of the combing reaction, such as ferric cyanide (Fe(CN)6 3- ), it is easier to generate interference signals, because higher electrode oxidation potential will oxidize more interference substances.

[0008] In addition to the chemical interferents mentioned above, glucose sensors also experience other test interferences. For example, the hematocrit percentage (%-HCT) is a significant interfering factor. This interference occurs when the medium, after the comb flow reaction, diffuses to the electrodes, hindered by blood cells, causing the diffusion coefficient to vary depending on the %-HCT. The current in the electrochemical reaction is affected by varying %-HCT. Therefore, factory batch calibration of sensor strips is typically centered around 42% HCT. If the user's %HCT is higher than 42%, the test will exhibit a negative bias. If the user's %HCT is lower than 42%, the test will exhibit a positive bias. Furthermore, the aging effects of the test strips during storage can interfere with blood glucose test results. Specifically, with extended storage, the sensor's sensitivity decreases, or more oxidizable substances are generated that contribute to the background signal. Another interfering factor is the test temperature.

[0009] Traditional blood glucose sensors generally apply voltage to electrodes in contact with the analyte sample, oxidizing the reduced mediator produced by the comb flow reaction, thereby generating a current signal responsive to the analyte. The current signal is then converted to the analyte concentration using a corresponding calculation method. Existing methods typically use different single parameters to eliminate or reduce interference compensation during the test, thereby improving test accuracy and precision. However, these single-parameter interference compensation methods often overlook the interplay between multiple interfering factors. For example, the interplay between temperature and HCT, the interplay between temperature and test strip aging, the interplay between HCT and test strip aging, and so on.

[0010] Therefore, in order to avoid the generation of interference signals, there is still much room for improvement in the method of testing blood glucose concentration in biological samples in terms of multi-pulse excitation and multi-parameter compensation, so as to further improve the accuracy and precision of testing blood glucose concentration in biological samples. Summary of the Invention

[0011] In order to solve the above problems, the present application discloses a method for calculating blood glucose concentration, the purpose of which is to solve the technical problem that the method of using a single parameter for interference compensation in the existing technology often ignores the mutual influence between multiple interference factors, resulting in low accuracy and precision of blood glucose concentration testing.

[0012] One aspect of the present application provides a method for calculating blood glucose concentration, which is applied to a biological sample analyte testing device, wherein the biological sample analyte testing device includes a first working electrode and a second working electrode, wherein the first working electrode is covered with a first chemical agent that can react with an analyte, and the second working electrode is a blank electrode, covered with an inert substance that does not chemically react with the analyte, or covered with a second chemical agent different from the first chemical agent, wherein a first excitation signal and a second excitation signal are input to the first working electrode, and after each excitation signal is completed, the first working electrode is in an open circuit state.

[0013] Between the first excitation signal and the second excitation signal, an excitation signal sequence is input to the second working electrode. After the excitation signal sequence is completed, the second working electrode is in an open circuit state; wherein the excitation signal sequence includes at least two continuous or discontinuous input signals, and each of the input signals is a constant value.

[0014] The output current of the first excitation signal, the second excitation signal, and the current collection point of the excitation signal sequence is collected at regular intervals to obtain an output current group, and the blood glucose concentration is obtained. The blood glucose concentration G is calculated as follows:

[0015] Among them, i 平均 is the average value of the output current of at least two current collection points in the second excitation signal, nA; S is i 平均 The slope of the linear equation with glucose concentration; i n and i j All are output currents in the output current group, nA; i 差 is the difference between the maximum output current of the excitation signal sequence and the output current of the last acquisition point, nA; the value range of N is 10~53; the value range of J is 10~53; X n The value range of X is -500 to 500; j The value range of is -15 to 15; the value range of K is -30 to 0.

[0016] This calculation method involves inputting a first excitation signal and a second excitation signal to a first working electrode. Between the first and second excitation signals, a sequence of excitation signals is input to the second working electrode. The input signals to the first and second working electrodes do not overlap in time. Specifically, after the excitation signal to the first working electrode is completed, the test device controls the first working electrode in an open-circuit state, and then initiates the excitation signal sequence to the second working electrode. After the excitation signal sequence to the second working electrode is completed, the test device controls the second working electrode in an open-circuit state, and then initiates the second excitation signal to the first working electrode. This pair of excitation signals input to the first and second working electrodes is defined as the "sandwich excitation method."

[0017] Furthermore, the method further includes applying an AC voltage to the second working electrode before inputting the first excitation signal to the working electrode to measure the impedance value of blood glucose, and obtaining the blood glucose concentration according to the output current group and the impedance value, wherein:

[0018] Where R is the impedance value, Ω; i m is the output current in the output current group, nA; M ranges from 10 to 53; X m The value range is -120 to 120.

[0019] Furthermore, the method further includes the step of obtaining the measured ambient temperature, and obtaining the blood glucose concentration according to the output current group, the impedance value and the temperature, wherein:

[0020] Where T is the ambient temperature, °C; i u is the output current in the output current group, nA; U ranges from 10 to 53; X u The value range is -7 to 3.

[0021] Optionally, the excitation time of the first excitation signal is 0.1-1s, and the excitation time of the second excitation signal is 0.1-2s.

[0022] Preferably, the excitation time of the first excitation signal is 0.5 s, and the excitation time of the second excitation signal is 1.25 s.

[0023] Optional, i 平均 is the average value of the output current of the last five current collection points in the second excitation signal.

[0024] Optionally, the voltage value of the first excitation signal is 0.2-0.4V, and the voltage value of the second excitation signal is 0.2-0.4V.

[0025] Preferably, the voltage values ​​of the first excitation signal and the second excitation signal are both 0.3V.

[0026] Optionally, the total application time of the excitation signal sequence is at least 1 s, and the application time of each input signal in the excitation signal sequence is 0.1-0.3 s.

[0027] Preferably, the application time of each input signal in the excitation signal sequence is equal, that is, 0.2 s.

[0028] Optionally, the voltage range of the excitation sequence is 0.1 to 3 V, and the excitation signal sequence includes 4 to 8 continuous input signals.

[0029] Preferably, the excitation signal sequence includes 5 consecutive input signals, and the voltage values ​​of the 5 consecutive input signals are 0.3V, 0.8V, 1.2V, 1.7V, and 2.2V respectively.

[0030] Optionally, the first excitation signal, the second excitation signal, and the output current of the current collection point of the excitation signal sequence are collected every 0.05 s.

[0031] Another aspect of the present application provides a sensor for testing an analyte in a biological sample, wherein the sensor is capable of executing the above-mentioned blood glucose concentration calculation method.

[0032] Compared with the prior art, the present invention achieves at least one of the following beneficial effects:

[0033] (1) The blood glucose concentration calculation method of the present application takes into account the mutual influence relationship between multiple interfering factors related to blood glucose concentration, further improving the accuracy and precision of the blood glucose concentration in the tested biological sample.

[0034] (2) The blood glucose concentration calculation method of the present application takes into account the mutual influence between various interference factors related to blood glucose concentration, making it possible to realize the barcode-free test strips leaving the factory. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0036] FIG1 shows an exemplary embodiment of a schematic diagram of the main excitation signals of the sandwich excitation method of the present application;

[0037] FIG2 shows the application i 平均 An exemplary embodiment of a linear relationship graph with glucose concentration;

[0038] FIG3 shows a comparison diagram of the deviations before and after calibration in Example 1;

[0039] FIG4 shows a comparison diagram of the deviations before and after calibration in Example 2;

[0040] FIG5 shows a comparison diagram of the deviations before and after calibration in Example 3;

[0041] FIG6 shows a comparison diagram of the deviations after calibration of Examples 1-3. DETAILED DESCRIPTION

[0042] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.

[0043] Many specific details are set forth in the following description to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0044] The excitation described in the disclosure of this application is intended to apply an input signal to an electrode in a biological testing device (e.g., a sensor), wherein the applied signal includes a positive or negative DC constant voltage or a positive or negative DC constant current source, etc., so as to cause a complete or partial oxidation or reduction reaction to occur on the electrode surface. The system processing center of the biological testing device applies the excitation input signal to the corresponding electrode through the connection port of the instrument and the test strip. When the predetermined excitation time ends, the system will no longer apply a signal to the electrode, and the electrode will be in an open circuit state. The open circuit state is not zero input. For example, inputting 0V (zero volts) to the electrode does not equal an open circuit. Zero voltage is also a type of input voltage. When the electrode is in the open circuit state, the oxidation-reduction state substances on the electrode surface and nearby will cause the residual signal to decay. This decay signal will provide a reflection of the state that the electrode has previously experienced, thereby recording other information related to the biological testing device and the analyte.

[0045] Example 1

[0046] The blood glucose concentration calculation method is applied to a biological sample analyte testing device, wherein the biological sample analyte testing device includes a first working electrode and a second working electrode, wherein the first working electrode is covered with a first chemical agent that can react with the analyte. Specifically, the first chemical agent includes a biological enzyme that can catalyze the analyte reaction, one or more mediators that can generate a combing effect between the enzyme reaction and the electrode reaction, and an inert substance that assists the chemical agent. The second working electrode is a blank electrode, covered with an inert substance that does not chemically react with the analyte, or covered with a second chemical agent different from the first chemical agent. A first excitation signal and a second excitation signal are input to the first working electrode, and after each excitation signal is completed, the first working electrode is in an open circuit state.

[0047] Between the first excitation signal and the second excitation signal, an excitation signal sequence is input to the second working electrode, and after the excitation signal sequence is completed, the second working electrode is in an open circuit state; wherein the excitation signal sequence includes at least two continuous or non-continuous input signals, and each of the input signals is a constant value;

[0048] At regular intervals, the first excitation signal, the second excitation signal, and the output current of the current collection point of the excitation signal sequence are collected to obtain an output current group, and the blood glucose concentration is obtained. The blood glucose concentration G is calculated using Formula 1.

[0049] Formula 1 is And G in formula 1 计算 It is obtained by formula 2, and f in formula 1 is obtained by formula 3, where f is the multi-parameter calibration factor.

[0050] Formula 2 is Among them, i 平均 is the average value of the output current of at least two current collection points in the second excitation signal, nA; S is i 平均 The slope of the linear equation with glucose concentration. For example, S is determined by the known history i 平均 And the historical glucose concentration is linearly fitted. Alternatively, the historical i 平均 After obtaining their linear relationship with historical glucose concentrations through statistical laws, they are directly tabulated and the slope S value is obtained by looking up the table.

[0051] Formula 3 is

[0052] Among them, i n and i j All are output currents in the output current group, nA; i 差 is the difference between the maximum output current of the excitation signal sequence and the output current of the last acquisition point, nA; the value range of N is 10~53; the value range of J is 10~53; X n The value range of X is -500 to 500; j The value range of is -15 to 15; the value range of K is -30 to 0.

[0053] Optional, i n and i j It can be the output current of the continuous sampling points in the output current group. For example, i n It can be i1, i2, i3, i4, i5, i6, i7, i8, i9, i 10 ;i j It can be i6, i7, i8, i9, i 10 、i 11 、i 12、i 13 、i 14 、i 15 Optional, i n and i j It can be the output current of non-continuous sampling points in the output current group. For example, i n It can be i3, i5, i 11 、i 13 、i 21 ;i j It can be i1, i2, i9, i 17 、i 20 、i 29 、i 30 However, the present application is not limited thereto, and those skilled in the art can select i according to the statistical significance test method. n and i j value.

[0054] Optionally, the excitation time of the first excitation signal is 0.1-1s, and the excitation time of the second excitation signal is 0.1-2s; preferably, the excitation time of the first excitation signal is 0.5s, and the excitation time of the second excitation signal is 1.25s.

[0055] Optional, i 平均 is the average value of the output current i of at least three current collection points in the second excitation signal. 平均 is the average value of the output current of the last five current collection points in the second excitation signal.

[0056] Optionally, the voltage value of the first excitation signal is 0.2-0.4V, and the voltage value of the second excitation signal is 0.2-0.4V; preferably, the voltage value of the first excitation signal and the second excitation signal are both 0.3V.

[0057] Optionally, the total application time of the excitation signal sequence is at least 1 s, and the application time of each input signal in the excitation signal sequence is 0.1-0.3 s; preferably, the application time of each input signal in the excitation signal sequence is equal, both being 0.2 s.

[0058] Optionally, the voltage range of the excitation sequence is 0.1~3V, and the excitation signal sequence includes 4-8 consecutive input signals; preferably, the excitation signal sequence includes 5 consecutive input signals, and the voltage values ​​of the 5 consecutive input signals are 0.3V, 0.8V, 1.2V, 1.7V, and 2.2V respectively.

[0059] Optionally, the first excitation signal, the second excitation signal, and the output current of the current collection point of the excitation signal sequence are collected every 0.05 s.

[0060] Example 2

[0061] Based on Example 1, the main difference is that it further includes a step of applying an AC voltage to the second working electrode before inputting the first excitation signal to the working electrode to measure the impedance value of blood glucose, and obtaining the blood glucose concentration based on the output current group and the impedance value, wherein,

[0062] Where R is the impedance value, Ω; i m is the output current in the output current group, nA; M ranges from 10 to 53; X m The value range is -120 to 120.

[0063] Compared with Example 1, Example 2 further considers the mutual influence between the impedance value and the output current.

[0064] Example 3

[0065] Based on Example 2, the method further includes the step of obtaining the measured ambient temperature, and obtaining the blood glucose concentration according to the output current group, the impedance value and the temperature, wherein:

[0066] Where T is the ambient temperature, °C; i u is the output current in the output current group, nA; U ranges from 10 to 53; X u The value range is -7 to 3.

[0067] Compared with Example 2, Example 3 further considers the mutual influence among the impedance value, ambient temperature and output current.

[0068] Experimental example

[0069] A sensor capable of executing the blood glucose concentration calculation method of the above-mentioned embodiments 1-3 is used to detect a blood sample to be tested. A calculation module is provided in the sensor, and the calculation module includes a calculation formula. The method and process of storing the calculation module are prior art and can be implemented by those skilled in the art, and will not be described in detail in this embodiment.

[0070] The test time and potential control in this test method are as follows: (1) a pre-test idle period of 1.25 seconds; during the test idle period, an AC voltage can be applied to the second working electrode to measure the impedance value of blood glucose; (2) a first excitation signal is applied to the first working electrode, a 0.3V potential difference is input to the first working electrode and the corresponding electrode for 0.5 seconds, and the output current is synchronously measured at intervals of 0.05 seconds; (3) after the first excitation signal ends, the first working electrode is set to an open circuit state, and the first potential decay signal of the first working electrode is measured at intervals of 0.005 seconds for 0.5 seconds; (4) while the first working electrode is in the open circuit state, an excitation signal is input to the second working electrode and the corresponding electrode. Signal sequence, the excitation signal sequence includes 5 excitations, the excitation voltage is 0.3V, 0.8V, 1.2V, 1.7V, 2.2V, each excitation lasts for 0.2 seconds, and the output current is measured synchronously at intervals of 0.05 seconds; (5) the second working electrode is set to an open circuit state; (6) after the first working electrode is open for 2.0 seconds, a second excitation signal is applied to the first working electrode with a voltage of 0.3V for 1.25 seconds, and the output current is measured synchronously at intervals of 0.05 seconds; (7) after the second excitation signal ends, the first working electrode is set to an open circuit state, and the potential decay signal of the corresponding electrode is measured at intervals of 0.005 seconds for 0.5 seconds. The total time of the above test steps is 1.25+0.5+2+1.25+0.5=5.5 seconds. Referring to Figure 1, Figure 1 shows a schematic diagram of the main excitation signals of the sandwich excitation method. In Figure 1, the horizontal axis represents the sensor test time, and the vertical axis represents the excitation signal intensity as the voltage applied to the electrode.

[0071] Referring to FIG2, FIG2 shows the history i 平均 The linear relationship between the graph and the historical glucose concentration is shown in Fig. 平均 is the average value of the output current of the last five current collection points in the second excitation signal.

[0072] In Example 1, f = -18.78 + 1.068i3 / i 平均 +3.46i5 / i 平均 -5.58i6 / i 平均 -5.14i9 / i 平均 +6.51i 10 / i 平均 -11.95i 12 / i 平均 -8.05i 18 / i 平均 +3.355i 21 / i 平均 +4.292i 23 / i 平均 -6.792i24 / i 平均 +0.991i 26 / i 平均 +0.3292i 30 / i 平均 +0.4228i 31 / i 平均 -2.718i 32 / i 平均 +1.779i 33 / i 平均 +0.790i 37 / i 平均 +18.22i 52 / i 平均 -0.1262i 差 i2 / i 平均 -0.2950i 差 i4 / i 平均 +2.740i 差 i8 / i 平均 -2.310i 差 i9 / i 平均 +1.201i 差 i 11 / i 平均 +1.653i 差 i 18 / i 平均 -0.909i 差 i 22 / i 平均 -1.059i 差 i 23 / i 平均 +1.466i 差 i 24 / i 平均 -0.01481i 差 i 27 / i 平均 -0.04952i 差 i 29 / i 平均 +0.3606i 差 i 32 / i 平均 -0.3276i 差 i 34 / i 平均 -0.298i 差 i 39 / i 平均 +0.228i 差 i 48 / i 平均 ;

[0073] In Example 2, f = -27.81 - 33.79i 12 / i 平均 +11.87i 19 / i 平均 +1.321i 23 / i 平均 -6.96i 26 / i 平均 -0.2726i 29 / i 平均 +0.1939i 31 / i 平均 +1.046i 33 / i 平均 +28.46i 52 / i 平均 -0.0742i 差 i2 / i 平均 +0.2468i 差 i8 / i 平均 +1.290i 差 i 11 / i 平均 -0.2111i 差 i 22 / i 平均 -0.3908i 差 i 23 / i 平均 +0.6853i 差 i 26 / i 平均 -0.02858i 差 i 30 / i 平均 +0.0447i 差 i 31 / i 平均 +0.3847i 差 i 33 / i 平均 -0.675i 差 i 34 / i 平均 +0.599i 差 i 37 / i 平均 -0.580i 差 i 39 / i 平均 +0.689Ri5 / i 平均 -0.839Ri6 / i 平均 +8.36Ri 13 / i 平均 -2.831Ri 19 / i 平均 +1.103Ri26 / i 平均 -0.02016Ri 27 / i 平均 +0.1339Ri 30 / i 平均 -0.3000Ri 32 / i 平均 ;

[0074] In Example 3, f = -18.27 - 51.0i 11 / i 平均 -3.232i 24 / i 平均 +4.20i 27 / i 平均 -4.77i 30 / i 平均 +12.12i 31 / i 平 均 -13.90i 32 / i 平均 -440i 51 / i 平均 +476i 52 / i 平均 +2.690i 差 i 12 / i 平均 +2.24i 差 i 14 / i 平均 -0.541i 差 i 23 / i 平均 +0.675i 差 i 24 / i 平均 +0.0220i 差 i 28 / i 平均 -0.1763i 差 i 29 / i 平均 +0.1496i 差 i 30 / i 平均 +0.0723i 差 i 31 / i 平均 -0.2146i 差 i 34 / i 平均 +0.890i 差 i 39 / i 平均 -0.908i 差 i 41 / i平均 +11.34Ri 11 / i 平均 +0.659Ri 23 / i 平均 -1.100Ri 27 / i 平均 +1.258Ri 30 / i 平均 -3.069Ri 31 / i 平均 +3.511Ri 32 / i 平均 +112.4Ri 51 / i 平均 -116.8Ri 52 / i 平均 -0.0202TG 计算 i 差 i2 / i 平均 +0.0574TG 计算 i 差 i3 / i 平均 -0.0318TG 计算 i 差 i4 / i 平均 +2.381TG 计算 i 差 i 11 / i 平均 -6.085TG 计算 i 差 i 12 / i 平均 +0.0665TG 计算 i 差 i 19 / i 平均 -0.1297TG 计算 i 差 i 22 / i 平均 -0.1133TG 计算 i 差 i 23 / i 平均 +0.1401TG 计算 i 差 i 26 / i 平均 +0.03416TG 计算 i 差 i 27 / i 平均 +0.1098TG 计算 i 差 i 29 / i 平均 -0.1481TG 计算 i差 i 30 / i 平均 -0.0645TG 计算 i 差 i 32 / i 平均 +0.0833TG 计算 i 差 i 33 / i 平均 -0.0434TG 计算 i 差 i 36 / i 平均 +0.02523TG 计算 i 差 i 53 / i 平均 ;

[0075] In order to verify the accuracy of the detection method of this embodiment, the following verification is performed:

[0076] 1. Determine the reference value of blood glucose concentration. Measure the reference value of blood glucose concentration using a YSI 2300 blood glucose analyzer.

[0077] 2. Calculate the deviation. The deviation is the absolute deviation, which is calculated as follows: Deviation = blood glucose concentration test value - blood glucose concentration reference value.

[0078] Referring to Table 1, Table 1 shows the percentage of deviations between Examples 1-3 and the blood glucose concentration reference value within each range.

[0079] Table 1

[0080] As shown in Table 1, it can be seen that the blood glucose concentration calculated by the present application is 66% within ±10%, 85% within ±15%, and 95% within ±20% compared with the reference value of blood glucose concentration measured by the YSI2300 blood glucose analyzer.

[0081] 3-5, which respectively show the deviation comparison diagrams before and after calibration of Examples 1-3, wherein the deviation before calibration is G 计算 A comparison chart of the deviations from the blood glucose concentration reference value shows the deviations from the blood glucose concentration detection value G of the present application after calibration. Figure 6 shows a comparison chart of the deviations from the blood glucose concentration reference value after calibration for Examples 1-3. It can be seen that the calibrated blood glucose concentration calculation method of the present application comprehensively considers the mutual influence between multiple interference factors related to blood glucose concentration, further improving the accuracy and precision of the blood glucose concentration in the biological sample tested.

[0082] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A method for calculating blood glucose concentration, wherein, The blood glucose concentration calculation method is applied to a biological sample analyte testing device, which includes a first working electrode and a second working electrode. The first working electrode is covered with a first chemical agent that can react with the analyte. The second working electrode is a blank electrode, covered with an inert substance that does not chemically react with the analyte, or covered with a second chemical agent different from the first chemical agent. A first excitation signal and a second excitation signal are input to the first working electrode, and after each excitation signal is completed, the first working electrode is in an open circuit state; After the excitation signal sequence is completed, the second working electrode is in an open circuit state; wherein, the excitation signal sequence includes at least two consecutive or non-consecutive input signals, and each input signal is a constant value; Collect the output currents at the current acquisition points of the first excitation signal, the second excitation signal, and the excitation signal sequence at regular intervals to obtain an output current group, and obtain the concentration of the blood glucose. The calculation method of the blood glucose concentration G is as follows: wherein, i 平均 is the average value of the output currents of at least two current acquisition points in the second excitation signal, in nA; S is the slope of the linear equation between i 平均 and the glucose concentration; i n and i j are both output currents in the output current group, in nA; i 差 is the difference between the maximum output current of the excitation signal sequence and the output current of the last acquisition point, in nA; the value range of N is 10 to 53; the value range of J is 10 to 53; X n has a value range of -500 to 500; X j has a value range of -15 to 15; the value range of K is -30 to 0.

2. The calculation method according to claim 1, wherein It further includes a step of applying an alternating voltage to a second working electrode before inputting a first excitation signal to the working electrode to measure the impedance value of blood glucose, and obtaining the concentration of the blood glucose according to the output current group and the impedance value. where R is the impedance value, in Ω; i m is the output current in the output current group, in nA; M ranges from 10 to 53; X m ranges from -120 to 120.

3. The calculation method according to claim 2, wherein, It further includes the step of obtaining the measured environmental temperature, and obtaining the concentration of the blood glucose according to the output current group, the impedance value and the temperature. Among them, T is the ambient temperature, °C; i u is the output current in the output current group, nA; the value range of U is 10 to 53; X u has a value range of -7 to 3.

4. The calculation method according to any one of claims 1 to 3, wherein, The excitation time of the first excitation signal is 0.1 - 1 s, and the excitation time of the second excitation signal is 0.1 - 2 s; Preferably, the excitation time of the first excitation signal is 0.5 s, and the excitation time of the second excitation signal is 1.25 s.

5. The calculation method according to claim 4, wherein, i 平均 It is the average value of the output currents at the last 5 current acquisition points in the second excitation signal.

6. The calculation method according to any one of claims 1 to 3, wherein, The voltage value of the first excitation signal is 0.2 - 0.4 V, and the voltage value of the second excitation signal is 0.2 - 0.4 V; Preferably, the voltage values of the first excitation signal and the second excitation signal are both 0.3 V.

7. The calculation method according to claim 6, wherein, The total application time of the excitation signal sequence is at least 1 s, and the application time of each input signal in the excitation signal sequence is 0.1 - 0.3 s; Preferably, the application time of each input signal in the excitation signal sequence is equal, both being 0.2 s.

8. The calculation method according to claim 6, wherein, The voltage range of the excitation sequence is 0.1 - 3 V, and the excitation signal sequence includes 4 - 8 consecutive input signals; Preferably, the excitation signal sequence includes 5 consecutive input signals, and the voltage values of the 5 consecutive input signals are 0.3 V, 0.8 V, 1.2 V, 1.7 V, and 2.2 V respectively.

9. The calculation method according to any one of claims 1-3, wherein, The output current of the current acquisition points of the first excitation signal, the second excitation signal, and the excitation signal sequence is acquired every 0.05 s.

10. A sensor for analyzing analytes in a biological sample, wherein, The sensor can execute the blood glucose concentration calculation method according to any one of claims 1 - 9.

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