Test strip sample suction judgment method

Abstract

The invention relates to a test strip sample suction judgment method, a test strip comprises a first sample introduction channel, a second sample introduction channel, a first electrode and a second electrode, and after it is determined that a sample enters the first sample introduction channel and the second sample introduction channel, alternating voltage is continuously applied to the first electrode and the second electrode according to a preset frequency; and acquiring a first mutation electric signal between the first electrode and the second electrode and a second mutation electric signal between the first electrode and the second electrode, and judging whether the test strip is full of the to-be-detected sample or not according to the first mutation electric signal, the second mutation electric signal and a preset threshold value. Whether the test strip is full of the sample to be detected or not can be effectively judged, so that an electrode for judging whether the sample injection is sufficient or not does not need to be additionally arranged in the test strip of the multi-index electrochemical sensor, and the overhead of an electrode material and the utilization of a test strip space can be effectively saved; furthermore, the accuracy of the detected concentration of the specific component in the to-be-detected sample can be effectively improved.

Description

Technical Field

[0001] This application belongs to the technical field of electrochemical biosensing, and particularly relates to a method for judging sample aspiration of a test strip. Background Art

[0002] Electrochemical sensors have always been used to detect or measure the presence of a certain substance in a fluid sample. By using an electrochemical sensor to detect an analyte in a sample (such as blood or blood-derived products, tears, urine, saliva, or other liquids), the concentration of a specific component in the sample (such as uric acid concentration, creatinine concentration, and hematocrit, etc.) can be detected.

[0003] Currently, when the dose of the sample to be tested applied to the test strip of an electrochemical sensor is insufficient, that is, when the test strip is not fully filled with the sample to be tested, it will cause the concentration of the specific component of the sample to be tested detected by the electrochemical sensor to be inaccurate, or directly report an error and unable to obtain a test result. Therefore, an additional electrode for judging whether the sample injection is sufficient is added to many electrochemical sensors, and this electrode is generally located at the innermost end of the sample injection channel in the sensor.

[0004] With the development of market demand, multi-index electrochemical sensors have also emerged, which can detect two or more indexes simultaneously through one sensor. The test strip of this kind of sensor generally has multiple electrodes. Each detection index generally requires a corresponding working electrode, and at the same time, other multiple electrodes such as hematocrit (HCT) electrodes, reference electrodes, or background electrodes are also required to cooperate to achieve accurate detection purposes. In this way, multiple electrodes need to be arranged inside the already narrow test strip, making the sample injection channel space of the test strip very crowded and leaving no extra space to arrange an electrode for judging whether the sample injection is sufficient.

[0005] Therefore, there is still room for improvement for this kind of multi-index electrochemical sensor. Summary of the Invention

[0006] The purpose of this application is to provide a method for judging sample aspiration of a test strip. Through the sample aspiration judgment method, it can effectively judge whether the test strip is fully filled with the sample to be tested, so that there is no need to additionally add an electrode for judging whether the sample injection is sufficient inside the test strip of a multi-index electrochemical sensor, which can effectively save the cost of electrode materials and the utilization of test strip space, and further improve the accuracy of the concentration of the specific component in the sample to be tested detected.

[0007] The technical solution provided by this application is as follows: A method for judging sample absorption of a test strip. The test strip includes a first sample inlet channel, a second sample inlet channel, a first electrode, and a second electrode. The first ends of the first sample inlet channel and the second sample inlet channel are connected through a sample inlet, and the second ends of the first sample inlet channel and the second sample inlet channel are connected through a communication hole. The first electrode is located in the first sample inlet channel, and the second electrode is located in the second sample inlet channel. The method includes: After it is determined that a sample has entered the first sample inlet channel and the second sample inlet channel, an alternating voltage is continuously applied to the first electrode and the second electrode at a predetermined frequency, and a first mutant electrical signal between the first electrode and the second electrode, and a second mutant electrical signal between the first electrode and the second electrode are obtained; Based on the first mutant electrical signal, the second mutant electrical signal, and a preset threshold, it is judged whether the test strip has been filled with the sample to be tested.

[0008] Optionally, if the first electrode is close to the second end of the first sample inlet channel and the second electrode is close to the second end of the second sample inlet channel, the judging whether the test strip has been filled with the sample to be tested based on the first mutant electrical signal, the second mutant electrical signal, and the preset threshold includes: Judging whether the first mutant electrical signal is greater than the preset threshold and the second mutant electrical signal is less than the preset threshold. If so, it is determined that the test strip has been filled with the sample to be tested. If not, it is determined that the test strip has not been filled with the sample to be tested.

[0009] Optionally, if the first electrode is close to the first end of the first sample inlet channel and the second electrode is close to the first end of the second sample inlet channel, the judging whether the test strip has been filled with the sample to be tested based on the first mutant electrical signal, the second mutant electrical signal, and the preset threshold includes: Judging whether the first mutant electrical signal is less than the preset threshold and the second mutant electrical signal is greater than the preset threshold. If so, it is determined that the test strip has been filled with the sample to be tested. If not, it is determined that the test strip has not been filled with the sample to be tested.

[0010] Optionally, the preset threshold is determined by the following method: Under each test condition randomly selected from multiple different temperatures and multiple different hematocrits, an alternating voltage is applied to the first electrode and the second electrode of multiple first test strips in an unfilled state at a predetermined frequency, and a first mutant test electrical signal between the first electrode and the second electrode of the multiple first test strips is obtained; Under each of various test conditions formed by arbitrarily selecting one combination from multiple different temperatures and multiple different hematocrits, an alternating voltage is applied to the first electrode and the second electrode of multiple second test strips in a fully filled state at a predetermined frequency, and a second mutant test electrical signal between the first electrode and the second electrode of multiple said second test strips is obtained; Based on the multiple said first mutant test electrical signals corresponding to each test condition, a first test mean value corresponding to each test condition is obtained, and a first test mean value set is constructed; Based on the multiple said second mutant test electrical signals corresponding to each test condition, a second test mean value corresponding to each test condition is obtained, and a second test mean value set is constructed; Based on the first test mean value set and the second test mean value set, a preset threshold is determined.

[0011] Optionally, the determining the preset threshold based on the first test mean value set and the second test mean value set includes: Determining the preset threshold based on the minimum value in the first test mean value set and the maximum value in the second test mean value set.

[0012] Optionally, the determining the preset threshold based on the minimum value in the first test mean value set and the maximum value in the second test mean value set includes: Taking the average value of the minimum value in the first test mean value set and the maximum value in the second test mean value set as the preset threshold.

[0013] Optionally, the taking the average value of the minimum value in the first test mean value set and the maximum value in the second test mean value set as the preset threshold includes: Based on the minimum value in the first test mean value set and the maximum value in the second test mean value set, an average value is obtained, and the value obtained by truncating the average value to two decimal places is used as the preset threshold.

[0014] Optionally, the taking the average value of the minimum value in the first test mean value set and the maximum value in the second test mean value set as the preset threshold includes: Based on the minimum value in the first test mean value set and the maximum value in the second test mean value set, an average value is obtained, and the integer value of the average value is used as the preset threshold.

[0015] Optionally, the first sample injection channel is located on the front side of the test strip, the second sample injection channel is located on the back side of the test strip, and the communication hole is a through hole penetrating the substrate of the test strip.

[0016] Optionally, the first sample injection channel and the second sample injection channel are located on the same side of the test strip. A partition is provided between the second ends of the first sample injection channel and the second sample injection channel, and the communication hole is provided on the partition.

[0017] Compared with the prior art, a method for judging sample absorption of a test strip provided by the present application. The test strip includes a first sample injection channel, a second sample injection channel, a first electrode, and a second electrode. The first ends of the first sample injection channel and the second sample injection channel are connected through a sample injection port, and the second ends of the first sample injection channel and the second sample injection channel are connected through a communication hole. The first electrode is located in the first sample injection channel, and the second electrode is located in the second sample injection channel. After it is determined that a sample has entered the first sample injection channel and the second sample injection channel, an alternating voltage is continuously applied to the first electrode and the second electrode at a predetermined frequency, and a first mutant electrical signal between the first electrode and the second electrode, and a second mutant electrical signal between the first electrode and the second electrode are obtained. Then, according to the first mutant electrical signal, the second mutant electrical signal, and a preset threshold, it is judged whether the test strip has absorbed the sample to be detected. By the above method in the present application, it is possible to effectively judge whether the test strip has absorbed the sample to be detected, so that there is no need to additionally add an electrode for judging whether the sample injection is sufficient in the test strip of the multi-index electrochemical sensor, which can effectively save the cost of electrode materials and the utilization of the test strip space, and further effectively improve the accuracy of detecting the concentration of a specific component in the sample to be detected. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0019] Figure 1 It is a schematic flowchart of a method for judging sample absorption of a test strip disclosed in an embodiment of the present application; Figure 2 It is a schematic diagram of the first front structure of a test strip disclosed in an embodiment of the present application; Figure 3 It is a schematic diagram of the first back structure of a test strip disclosed in an embodiment of the present application; Figure 4 It is a schematic diagram of the second front structure of a test strip disclosed in an embodiment of the present application; Figure 5 It is a schematic diagram of the second back structure of a test strip disclosed in an embodiment of the present application; Figure 6 It is a schematic diagram of the third structure of a test strip disclosed in an embodiment of the present application; Figure 7 is Figure 6 the A-A sectional view of Figure 8 is Figure 7 the enlarged partial view of I in Figure 9 the structural schematic diagram of another test strip disclosed in the embodiment of the present application; Reference numerals: 11 - first sample injection channel; 12 - second sample injection channel; 13 - sample injection port; 14 - communication hole; 15 - substrate; 16 - partition member; 21 - first electrode; 22 - second electrode; 23 - third electrode; 24 - fourth electrode; 25 - fifth electrode; 26 - sixth electrode; 27 - seventh electrode. Detailed implementation manners

[0020] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present application.

[0021] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly disposed on the other element; when an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0022] It should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0023] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "a plurality of" and "several" is two or more, unless otherwise specifically defined.

[0024] It should be noted that the structures, proportions, sizes, etc. shown in the accompanying drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they do not have substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size, without affecting the efficacy that this application can produce and the purpose that can be achieved, should still fall within the scope covered by the technical content disclosed in this application.

[0025] As Figure 1 shown, this embodiment provides a method for judging sample aspiration of a test strip. As Figure 2 , Figure 3 , Figure 8 and Figure 9 shown, the test strip includes a first sample injection channel 11, a second sample injection channel 12, a first electrode 21, and a second electrode 22. The first end of the first sample injection channel 11 and the first end of the second sample injection channel 12 are connected through a sample injection port 13, and the second end of the first sample injection channel 11 and the second end of the second sample injection channel 12 are connected through a communication hole 14. The first electrode 21 is located in the first sample injection channel 11, and the second electrode 22 is located in the second sample injection channel 12. The method includes: S11. After it is determined that a sample has entered the first sample injection channel and the second sample injection channel, an alternating voltage is continuously applied to the first electrode and the second electrode at a predetermined frequency, and a first mutation electrical signal between the first electrode and the second electrode, and a second mutation electrical signal between the first electrode and the second electrode are acquired; In this embodiment, the diameter range of the communication hole can be 0.2 mm - 1.3 mm, preferably the diameter of the communication hole is 0.5 mm. The sample can be a blood sample, or other body fluid samples such as tear fluid, urine, and saliva, or a non-body fluid sample. Preferably, the sample is a blood sample. The predetermined frequency is a preset frequency. The first mutation electrical signal and the second mutation electrical signal can be impedance values or current values. Preferably, the first mutation electrical signal and the second mutation electrical signal are impedance values.

[0026] In this embodiment, according to the situation of the sample covering the electrode after the sample is applied from the sample injection port to the first sample injection channel and the second sample injection channel, it is divided into three stages, specifically as follows: The first stage: After entering the first sample injection channel and the second sample injection channel from the sample injection port, when the sample has not contacted the first electrode or the second electrode (at least one electrode has not contacted the sample), the first electrode and the second electrode are open-circuited, and the impedance between the first electrode and the second electrode is equivalent to infinity; The second stage: As the sample flows into the first injection channel and the second injection channel, the sample will cover the first electrode and the second electrode. When there is sample at the injection port, the first electrode and the second electrode are connected, and the impedance between the first electrode and the second electrode obtained changes suddenly from infinity to the first impedance Z1, that is, the first mutation electrical signal. Among them, the first impedance Z1 is proportional to the sum of the distance from the first electrode to the injection port and the distance from the injection port to the second electrode; The third stage: As the sample continues to flow into the first injection channel and the second injection channel, the injection port is disconnected from the sample, and when there is sample at the communication hole, the first electrode and the second electrode are connected. The impedance between the first electrode and the second electrode obtained changes suddenly from the first impedance Z1 to the second impedance Z2, that is, the second mutation electrical signal. Among them, the second impedance Z2 is proportional to the sum of the distance from the first electrode to the communication hole and the distance from the communication hole to the second electrode; Since the first impedance Z1 is proportional to the sum of the distance from the first electrode to the sampling port and the distance from the sampling port to the second electrode, and the second impedance Z2 is proportional to the sum of the distance from the first electrode to the communication hole and the distance from the communication hole to the second electrode, if the first electrode is close to the second end of the first sampling channel and the second electrode is close to the second end of the second sampling channel, that is, both the first electrode and the second electrode are close to the communication hole, then the second impedance Z2 will be much smaller than the first impedance Z1, that is, the second mutation signal will be much smaller than the first mutation signal. If the first electrode is close to the first end of the first sampling channel and the second electrode is close to the first end of the second sampling channel, that is, both the first electrode and the second electrode are close to the sampling port, then the second impedance Z2 will be much larger than the first impedance Z1, that is, the second mutation signal will be much larger than the first mutation signal. Substantially, according to the detection purpose of the test strip, multiple electrodes are designed in each sampling channel at different positions in the sampling channel, and each electrode can be selected as the first electrode and the second electrode for sampling judgment in this application. There can be various situations for the relative positions between the two selected electrodes; for example, the first electrode may be located at the first end, the second end, or a position between the two ends of the first sampling channel. Similarly, the second electrode may also be located at the first end, the second end, or a position between the two ends of the second sampling channel. In this way, when arbitrarily selecting two electrodes to form the first electrode and the second electrode, there will be many variation situations for the distances between the first electrode and the second electrode and the sampling port and the communication hole respectively, resulting in many variation situations for the magnitude relationship between the first impedance Z1 and the second impedance Z2. Regardless of which position of the electrodes is selected to form the first electrode and the second electrode, the influence of the different electrode positions on the first impedance Z1 and the second impedance Z2 and their magnitude relationship can be analyzed according to the three stages of the sample flowing in the sampling channel as described above. In this way, the corresponding preset threshold can also be determined according to the preset threshold determination method in this application to achieve the purpose of sampling judgment. Therefore, the specific positions of the first electrode and the second electrode in the first sampling channel and the second sampling channel in this application can be arbitrarily selected. Since there are many different positions of the electrodes in the sampling channel, and there are also many combinations of selecting one position of the electrodes from the two sampling channels to form the first electrode and the second electrode. To concisely describe the solution of this application, the judgment relationship between the two mutation signals and the preset threshold in the following step S12 and subsequent descriptions only represents the situation where the first electrode and the second electrode are synchronously located close to the same end of the sampling channel, rather than restricting that the first electrode and the second electrode can only be located at the same end position in the sampling channel. In other situations of various electrode positions, the sampling judgment principle and the preset threshold determination method are the same.

[0027] S12. Determine whether the test strip has been filled with the sample to be tested according to the first mutation signal, the second mutation signal, and the preset threshold.

[0028] In this embodiment, the preset threshold is a threshold set in advance. Since if the first electrode is close to the second end of the first sample injection channel and the second electrode is close to the second end of the second sample injection channel, the obtained second mutant electrical signal is much smaller than the first mutant electrical signal, and if the first electrode is close to the first end of the first sample injection channel and the second electrode is close to the first end of the second sample injection channel, the obtained second mutant electrical signal is much larger than the first mutant electrical signal. Therefore, the first mutant electrical signal and the second mutant electrical signal can be respectively compared with the preset threshold, and whether the test strip has been filled with the sample to be tested can be judged according to the comparison result.

[0029] Compared with the prior art, for a method for judging sample absorption of a test strip provided in this application, the test strip includes a first sample injection channel, a second sample injection channel, a first electrode and a second electrode. The first end of the first sample injection channel and the first end of the second sample injection channel are connected through a sample injection port. The second end of the first sample injection channel and the second end of the second sample injection channel are connected through a communication hole. The first electrode is located in the first sample injection channel, and the second electrode is located in the second sample injection channel. After it is determined that a sample has entered the first sample injection channel and the second sample injection channel, an alternating voltage is continuously applied to the first electrode and the second electrode at a predetermined frequency, and a first mutant electrical signal between the first electrode and the second electrode, and a second mutant electrical signal between the first electrode and the second electrode are obtained. Then, according to the first mutant electrical signal, the second mutant electrical signal and the preset threshold, it is judged whether the test strip has been filled with the sample to be tested. Through the above method in this application, it can be effectively judged whether the test strip has been filled with the sample to be tested, so that there is no need to additionally add an electrode for judging whether the sample injection is sufficient in the test strip of the multi-index electrochemical sensor, which can effectively save the cost of electrode materials and the utilization of the test strip space, and further can effectively improve the accuracy of the concentration of the specific component in the sample to be tested detected.

[0030] As an implementation manner, in the embodiment of this application, if the first electrode is close to the second end of the first sample injection channel and the second electrode is close to the second end of the second sample injection channel, judging whether the test strip has been filled with the sample to be tested according to the first mutant electrical signal, the second mutant electrical signal and the preset threshold includes: Judging whether the first mutant electrical signal is greater than the preset threshold and the second mutant electrical signal is less than the preset threshold. If so, it is determined that the test strip has been filled with the sample to be tested. If not, it is determined that the test strip has not been filled with the sample to be tested.

[0031] In this embodiment, if the first electrode is close to the second end of the first sampling channel and the second electrode is close to the second end of the second sampling channel, it is determined whether the first mutant electrical signal is greater than a preset threshold and the second mutant electrical signal is less than the preset threshold. If the first mutant electrical signal is greater than the preset threshold and the second mutant electrical signal is less than the preset threshold, it is determined that the test strip has been filled with the sample to be tested. If the first mutant electrical signal is less than or equal to the preset threshold and the second mutant electrical signal is greater than or equal to the preset threshold, it is determined that the test strip has not been filled with the sample to be tested.

[0032] As an implementation manner, in the embodiment of the present application, if the first electrode is close to the first end of the first sampling channel and the second electrode is close to the first end of the second sampling channel, it is determined whether the test strip has been filled with the sample to be tested according to the first mutant electrical signal, the second mutant electrical signal and the preset threshold, including: It is determined whether the first mutant electrical signal is less than the preset threshold and the second mutant electrical signal is greater than the preset threshold. If so, it is determined that the test strip has been filled with the sample to be tested. If not, it is determined that the test strip has not been filled with the sample to be tested.

[0033] In this embodiment, if the first electrode is close to the first end of the first sampling channel and the second electrode is close to the first end of the second sampling channel, it is determined whether the first mutant electrical signal is less than the preset threshold and the second mutant electrical signal is greater than the preset threshold. If the first mutant electrical signal is less than the preset threshold and the second mutant electrical signal is greater than the preset threshold, it is determined that the test strip has been filled with the sample to be tested. If the first mutant electrical signal is greater than or equal to the preset threshold and the second mutant electrical signal is less than or equal to the preset threshold, it is determined that the test strip has not been filled with the sample to be tested.

[0034] As an implementation manner, in the embodiment of the present application, the preset threshold is determined by the following method: S21. Under each of the test conditions formed by arbitrarily selecting one from multiple different temperatures and multiple different hematocrits, an alternating voltage is applied to the first electrode and the second electrode of a plurality of first test strips in an unfilled state at a predetermined frequency, and a first mutant test electrical signal between the first electrode and the second electrode of the plurality of first test strips is obtained; In this embodiment, the first test strip is a test strip for testing with the same Figure 2 strip structure as that in. The multiple different temperatures may include three values of 5 °C, 25 °C and 45 °C, and may also include other more temperature values. The multiple different hematocrits may include seven values of HCT10%, HCT20%, HCT30%, HCT40%, HCT50%, HCT60% and HCT70%, and may also include other more hematocrit values.

[0035] In this embodiment, a plurality of first test strips are prepared according to the number of test conditions and the number of tests for each test condition. A test condition formed by selecting one temperature from a plurality of different temperatures and one hematocrit from a plurality of different hematocrits is used as the current test condition. Under the current test condition, a first test strip is selected as the current test strip, and the first test strip is in an unfilled state. An alternating voltage is applied to the first electrode and the second electrode of the first test strip at a predetermined frequency, and a first mutant test electrical signal between the first electrode and the second electrode of the first test strip is obtained. In this way, multiple tests are performed to obtain the first mutant test electrical signals between the first electrode and the second electrode of a plurality of first test strips corresponding to the current test condition. In this way, until the first mutant test electrical signals between the first electrode and the second electrode of a plurality of first test strips in an unfilled state corresponding to each test condition are obtained.

[0036] Specifically, according to the temperatures of 5°C, 25°C, and 45°C, combined with the hematocrits of HCT 10%, HCT 20%, HCT 30%, HCT 40%, HCT 50%, HCT 60%, and HCT 70%, 21 test conditions are formed. Each test condition needs to be tested 10 times, and 210 first test strips can be prepared. The test condition formed by selecting the temperature of 5°C from the temperatures of 5°C, 25°C, and 45°C and the hematocrit of HCT 10% from the hematocrits of HCT 10%, HCT 20%, HCT 30%, HCT 40%, HCT 50%, HCT 60%, and HCT 70% is used as the current test condition. Under the test condition of a temperature of 5°C and a hematocrit of 10% HCT, a first test strip is selected as the current test strip, and the first test strip is in an unfilled state. An alternating voltage is applied to the first electrode and the second electrode of the first test strip at a predetermined frequency, and the first mutant test electrical signal between the first electrode and the second electrode of the first test strip in an unfilled sample injection state is obtained. Then, in this way, 10 tests are performed in total to obtain the first mutant test electrical signals between the first electrode and the second electrode of 10 first test strips corresponding to the test condition of a temperature of 5°C and a hematocrit of 10% HCT. In this way, until the first mutant test electrical signals between the first electrode and the second electrode of 10 first test strips corresponding to each hematocrit, i.e., HCT, and each temperature are obtained. The test results are shown in Tables 1 to 7 below: Table 1 10 first mutant test electrical signals corresponding to HCT 10% and each temperature

[0037] Table 2 10 first mutant test electrical signals corresponding to HCT 20% and each temperature

[0038] Table 3. 10 first mutation test electrical signals corresponding to HCT 30% and each temperature

[0039] Table 4. 10 first mutation test electrical signals corresponding to HCT 40% and each temperature

[0040] Table 5. 10 first mutation test electrical signals corresponding to HCT 50% and each temperature

[0041] Table 6. 10 first mutation test electrical signals corresponding to HCT 60% and each temperature

[0042] Table 7. 10 first mutation test electrical signals corresponding to HCT 70% and each temperature

[0043] Wherein, Z1 is the first mutation test electrical signal. Specifically, Z1 is the first test impedance value.

[0044] S22. Under each test condition formed by arbitrarily selecting one combination from multiple different temperatures and multiple different hematocrits, an alternating voltage is applied to the first electrode and the second electrode of multiple second test strips in a fully absorbed state at a predetermined frequency, and the second mutation test electrical signal between the first electrode and the second electrode of multiple second test strips is obtained; In this embodiment, the second test strip is a test strip for testing with the same Figure 2 test strip structure as that in. Multiple different temperatures may include three values of 5°C, 25°C, and 45°C, and may also include other more temperature values. Multiple different hematocrits may include seven values of HCT 10%, HCT 20%, HCT 30%, HCT 40%, HCT 50%, HCT 60%, and HCT 70%, and may also include other more hematocrit values.

[0045] In this embodiment, multiple second test strips are prepared according to the number of test conditions and the number of tests for each test condition. A test condition formed by selecting one temperature from multiple different temperatures and one hematocrit from multiple different hematocrits is used as the current test condition. Under the current test condition, one second test strip is selected as the current test strip, and the second test strip is made to be in a fully-absorbed state. An alternating voltage is applied to the first electrode and the second electrode of the second test strip at a predetermined frequency, and a second mutation test electrical signal between the first electrode and the second electrode of the second test strip is obtained. In this way, multiple tests are conducted to obtain the second mutation test electrical signals between the first electrode and the second electrode of multiple second test strips corresponding to the current test condition. In this way, until the second mutation test electrical signals between the first electrode and the second electrode of multiple second test strips in a fully-absorbed state corresponding to each test condition are obtained.

[0046] Specifically, according to the temperatures of 5°C, 25°C, and 45°C, combined with the hematocrits of HCT 10%, HCT 20%, HCT 30%, HCT 40%, HCT 50%, HCT 60%, and HCT 70%, 21 test conditions are formed. Each test condition needs to be tested 10 times, so 210 second test strips can be prepared. Select the temperature of 5°C from the temperatures of 5°C, 25°C, and 45°C, and select the hematocrit of HCT 10% from the hematocrits of HCT 10%, HCT 20%, HCT 30%, HCT 40%, HCT 50%, HCT 60%, and HCT 70% to form the test condition as the current test condition. Under the test condition of a temperature of 5°C and a hematocrit of 10% HCT, one second test strip is selected as the current test strip, and the second test strip is made to be in a fully-absorbed state. An alternating voltage is applied to the first electrode and the second electrode of the second test strip at a predetermined frequency, and the second mutation test electrical signal between the first electrode and the second electrode of the second test strip in a fully-absorbed sample-introducing state is obtained. Then, in this way, 10 tests are conducted in total to obtain the second mutation test electrical signals between the first electrode and the second electrode of 10 second test strips corresponding to the test condition of a temperature of 5°C and a hematocrit of 10% HCT. In this way, until the second mutation test electrical signals between the first electrode and the second electrode of 10 second test strips corresponding to each hematocrit, i.e., HCT, and each temperature are obtained. The test results are shown in Tables 8 to 14 below: Table 8: 10 second mutation test electrical signals corresponding to HCT 10% and each temperature

[0047] Table 9: 10 second mutation test electrical signals corresponding to HCT 20% and each temperature

[0048] Table 10: 10 second mutation test electrical signals corresponding to HCT 30% and each temperature

[0049] Table 11: 10 second mutation test electrical signals corresponding to HCT 40% and each temperature

[0050] Table 12: 10 second mutation test electrical signals corresponding to HCT 50% and each temperature

[0051] Table 13: 10 second mutation test electrical signals corresponding to HCT 60% and each temperature

[0052] Table 14: 10 second mutation test electrical signals corresponding to HCT 70% and each temperature

[0053] Among them, Z2 is the second mutation test electrical signal. Specifically, Z2 is the second test impedance value.

[0054] S23. Obtain the first test mean value corresponding to each test condition based on the multiple first mutation test electrical signals corresponding to each test condition, and construct a first test mean value set; In this embodiment, the multiple first mutation test electrical signals corresponding to each test condition can be accumulated and then divided by the number to obtain the first test mean value corresponding to each test condition, and a first test mean value set is constructed.

[0055] Specifically, according to the data in Tables 1 to 7, the 10 first test impedance values corresponding to the test condition of temperature 5°C and hematocrit 10% can be accumulated and then divided by the number 10 to obtain the first test mean value 17509.569 corresponding to the test condition of temperature 5°C and hematocrit 10%. In this way, the first test mean values corresponding to 21 test conditions are obtained, and a first test mean value set including 17509.569, 10609.569, 7609.569, 21741.782, 12391.782, 8741.782, 28116.639, 14116.639, 10116.639, 31612.604, 15802.604, 11372.604, 37631, 17631, 12831, 43571.957, 19871.957, 14871.957, 47728.659, 21128.659, 16128.659 is constructed.

[0056] S24. Obtain the second test mean values corresponding to each test condition based on the multiple second mutant test electrical signals corresponding to each test condition, and construct a second test mean value set; In this embodiment, the multiple second mutant test electrical signals corresponding to each test condition can be accumulated and then divided by the number to obtain the second test mean values corresponding to each test condition, and a second test mean value set is constructed.

[0057] Specifically, according to the data in Tables 8 to 14, the 10 second test impedance values corresponding to the test conditions of a temperature of 5°C and a hematocrit of 10% can be accumulated and then divided by the number 10 to obtain the second test mean value of 1236.415 corresponding to the test conditions of a temperature of 5°C and a hematocrit of 10%. In this way, the second test mean values corresponding to 21 test conditions are obtained, and a second test mean value set including 1236.415, 1036.415, 536.415, 1455.845, 1155.845, 655.845, 1890.947, 1390.947, 890.947, 2100.634, 1600.634, 1100.63, 2585.318, 1815.318, 1315.318, 3002.732, 2202.732, 1702.732, 3361.426, 2561.426, 2275.98 is constructed.

[0058] S25. Determine a preset threshold according to the first test mean value set and the second test mean value set.

[0059] In this embodiment, the preset threshold can be determined according to the minimum value in the first test mean value set and the maximum value in the second test mean value set, or the preset threshold can be determined according to the second smallest value in the first test mean value set and the maximum value in the second test mean value set.

[0060] As an implementation manner, in the embodiments of the present application, determining a preset threshold according to the first test mean value set and the second test mean value set includes: Determine a preset threshold according to the minimum value in the first test mean value set and the maximum value in the second test mean value set.

[0061] In this embodiment, the average value of the minimum value in the first test mean value set and the maximum value in the second test mean value set can be taken as the preset threshold; or the value obtained by truncating the average value of the minimum value in the first test mean value set and the maximum value in the second test mean value set to two decimal places can be taken as the preset threshold; or the integer value of the average value of the minimum value in the first test mean value set and the maximum value in the second test mean value set can be taken as the preset threshold.

[0062] As an implementation manner, in the embodiments of the present application, determining a preset threshold according to the minimum value in the first test mean set and the maximum value in the second test mean set includes: Taking the average value of the minimum value in the first test mean set and the maximum value in the second test mean set as the preset threshold.

[0063] In this embodiment, by taking the average value of the minimum value in the first test mean set corresponding to multiple test conditions and the maximum value in the second test mean set as the preset threshold, the accuracy of sampling judgment can be effectively guaranteed under various temperature and hematocrit conditions.

[0064] Specifically, the minimum value in the first test mean set is 7609.569, the maximum value in the second test mean set is 3361.426, and the average value of the minimum value 7609.569 in the first test mean set and the maximum value 3361.426 in the second test mean set is 5485.4975. 5485.4975 can be used as the preset threshold.

[0065] As an implementation manner, in the embodiments of the present application, taking the average value of the minimum value in the first test mean set and the maximum value in the second test mean set as the preset threshold includes: Obtaining an average value according to the minimum value in the first test mean set and the maximum value in the second test mean set, and taking the value obtained by truncating the average value to two decimal places as the preset threshold.

[0066] In this embodiment, in view of reducing the instrument cost, an average value of the minimum value in the first test mean set and the maximum value in the second test mean set can be obtained according to the minimum value in the first test mean set and the maximum value in the second test mean set, and the value obtained by truncating the average value to two decimal places is taken as the preset threshold.

[0067] Specifically, the average value 5485.4975 of the minimum value in the first test mean set and the maximum value in the second test mean set can be truncated to two decimal places to obtain the value 5485.49 after truncating to two decimal places, and the value 5485.49 after truncating to two decimal places is taken as the preset threshold.

[0068] As an implementation manner, in the embodiments of the present application, taking the average value of the minimum value in the first test mean set and the maximum value in the second test mean set as the preset threshold includes: Obtaining an average value according to the minimum value in the first test mean set and the maximum value in the second test mean set, and taking the value obtained by rounding the average value as the preset threshold.

[0069] In this embodiment, in view of further reducing the instrument cost, the average value of the minimum value in the first test mean set and the maximum value in the second test mean set can be obtained, and the rounded value of the average value is used as the preset threshold.

[0070] Specifically, the average value 5485.4975 of the minimum value in the first test mean set and the maximum value in the second test mean set can be rounded to obtain the rounded value 5485, and the rounded value 5485 is used as the preset threshold.

[0071] As Figures 6 to 8 shown, as an implementation manner, in the embodiment of the present application, the first sample injection channel 11 is located on the front side of the test strip, the second sample injection channel 12 is located on the back side of the test strip, and the communication hole 14 is a through hole penetrating the substrate 15 of the test strip.

[0072] In this embodiment, the first electrode 21 located in the first sample injection channel 11 is located on the front side of the test strip, and the second electrode 22 located in the second sample injection channel 12 is located on the back side of the test strip. By arranging the first electrode 21 and the second electrode 22 on the front and back sides of the test strip, the interference between the electrodes can be effectively reduced, and the stability of the detection signal can be effectively improved.

[0073] As Figure 9 shown, as an implementation manner, in the embodiment of the present application, the first sample injection channel 11 and the second sample injection channel 12 are located on the same side of the test strip, a partition member 16 is provided between the second ends of the first sample injection channel 11 and the second sample injection channel 12, and the communication hole 14 is provided on the partition member 16.

[0074] In this embodiment, the first electrode 21 located in the first sample injection channel 11 and the second electrode 22 located in the second sample injection channel 12 are located on the same side of the test strip. By arranging the first electrode 21, the first sample injection channel 11, the second electrode 22, and the second sample injection channel 12 on the same side of the test strip, it can be completed by a single printing, etching, or injection molding process, reducing the precision requirements for double-sided alignment, reducing the production complexity, and there is no need to process electrodes and channels on both sides of the test strip respectively, saving materials (such as conductive coatings, insulating layers, etc.).

[0075] As Figure 4 and Figure 5As shown in the figure, as an embodiment, in the embodiment of the present application, the test strip further includes a third electrode 23 and a fourth electrode 24 on the front side, and a fifth electrode 25, a sixth electrode 26 and a seventh electrode 27 on the back side. The third electrode 23 is close to the first end of the first sampling channel 11, the first electrode 21 is close to the second end of the first sampling channel 11, the fourth electrode 24 is located between the third electrode 23 and the first electrode 21, the fifth electrode 25 is close to the first end of the second sampling channel 12, the second electrode 22 is close to the second end of the first sampling channel 11, the sixth electrode 26 is located between the fifth electrode 25 and the seventh electrode 27, and the seventh electrode 27 is located between the sixth electrode 26 and the second electrode 22; the first electrode 21, the third electrode 23 and the fourth electrode 24 are respectively any one of the exclusive first detection index working electrode, the second detection index working electrode, and the first reference electrode; the second electrode 22, the fifth electrode 25 to the seventh electrode 27 are respectively any one of the exclusive first HCT electrode, the second HCT electrode, the background electrode, and the second reference electrode.

[0076] In this embodiment, the sample to be tested is a blood sample, and the detection index corresponding to each working electrode can be selected from the following indexes: common electrochemical detection indexes such as uric acid, creatinine, blood glucose, blood ketone, lactic acid, hemoglobin, glycated hemoglobin, cholesterol, lipoprotein, triglyceride, and so on.

[0077] Specifically, the first electrode 21 is a creatinine working electrode, the third electrode 23 is a uric acid working electrode, the fourth electrode 24 is a uric acid and creatinine reference electrode, the second electrode 22 is a creatinine background reference electrode, the fifth electrode 25 is a first HCT electrode, the sixth electrode 26 is a second HCT electrode, and the seventh electrode 27 is a creatinine background electrode.

[0078] The indicator detection process of the uric acid creatinine dual-index electrochemical test strip is briefly described. The uric acid working electrode is coated with uricase solution, the creatinine working electrode is coated with creatinine working enzyme solution, and the creatinine background electrode is coated with creatinine background enzyme solution. An AC excitation voltage of a preset frequency is applied between the first HCT electrode and the second HCT electrode to obtain an impedance signal of the blood sample between the first HCT electrode and the second HCT electrode. The impedance signal is substituted into a preset linear equation to obtain the hematocrit of the blood sample, i.e., HCT, wherein the preset frequency is a preset frequency, and the preset linear equation is an equation fitted according to the test results; a weak DC excitation voltage is applied between the creatinine background electrode and the creatinine background reference electrode, and a DC excitation voltage is applied between the creatinine background electrode and the creatinine background reference electrode. A creatinine background current signal can be measured, a weak DC excitation voltage is applied between the creatinine working electrode and the uric acid and creatinine reference electrode, and a creatinine working current signal can be detected on the creatinine working electrode. This current signal is proportional to the creatinine concentration in the blood. The creatinine working current signal can be subjected to data compensation and correction processing according to the creatinine background current signal to obtain a corrected current signal representing the creatinine concentration of the blood to be tested. For example, the creatinine working current signal is subtracted from the creatinine background current signal to obtain a subtracted current signal representing the creatinine concentration of the blood to be tested; a weak DC excitation voltage is applied between the uric acid working electrode and the uric acid and creatinine reference electrode, and a current signal representing the uric acid concentration of the blood to be tested can be detected on the uric acid working electrode.

[0079] In this embodiment, by arranging the creatinine working electrode and the creatinine background electrode on the front and back sides of the test strip, the mutual contamination between the creatinine working enzyme solution and the creatinine background enzyme solution can be effectively avoided, and the detection accuracy of the creatinine concentration can be effectively improved.

[0080] In this embodiment, since the uricase solution does not contain an electron mediator, the uric acid working electrode is arranged at the first end close to the first injection channel 11, that is, close to the injection port 13, so that the sample first flows through the uric acid working electrode and then flows through the creatinine working electrode, so that the uricase solution will not affect the detection of the creatinine working current signal.

[0081] The embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referenced to each other.

[0082] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for judging sample absorption of a test strip, characterized in that The test strip includes a first sample injection channel, a second sample injection channel, a first electrode, and a second electrode. The first ends of the first sample injection channel and the second sample injection channel are connected through a sample injection port. The second ends of the first sample injection channel and the second sample injection channel are connected through a communication hole. The first electrode is located in the first sample injection channel, and the second electrode is located in the second sample injection channel. The method includes: After determining that a sample has entered the first sample injection channel and the second sample injection channel, an alternating voltage is continuously applied to the first electrode and the second electrode at a predetermined frequency, and a first mutation electrical signal between the first electrode and the second electrode, and a second mutation electrical signal between the first electrode and the second electrode are acquired; Based on the first mutation electrical signal, the second mutation electrical signal, and a preset threshold, it is determined whether the test strip has been filled with the sample to be tested.

2. The method according to claim 1, wherein If the first electrode is close to the second end of the first sample injection channel and the second electrode is close to the second end of the second sample injection channel, then based on the first mutation electrical signal, the second mutation electrical signal, and the preset threshold, determining whether the test strip has been filled with the sample to be tested includes: Determining whether the first mutation electrical signal is greater than the preset threshold and the second mutation electrical signal is less than the preset threshold. If so, it is determined that the test strip has been filled with the sample to be tested. If not, it is determined that the test strip has not been filled with the sample to be tested.

3. The method according to claim 1, wherein If the first electrode is close to the first end of the first sample injection channel and the second electrode is close to the first end of the second sample injection channel, then based on the first mutation electrical signal, the second mutation electrical signal, and the preset threshold, determining whether the test strip has been filled with the sample to be tested includes: Determining whether the first mutation electrical signal is less than the preset threshold and the second mutation electrical signal is greater than the preset threshold. If so, it is determined that the test strip has been filled with the sample to be tested. If not, it is determined that the test strip has not been filled with the sample to be tested.

4. The method according to claim 2, wherein The preset threshold is determined by the following method: Under each of various test conditions formed by arbitrarily selecting one from multiple different temperatures and multiple different hematocrits, an alternating voltage is applied to the first electrode and the second electrode of multiple first test strips in an unfilled state at a predetermined frequency, and a first mutation test electrical signal between the first electrode and the second electrode of the multiple first test strips is acquired; Under each of various test conditions formed by arbitrarily selecting one from multiple different temperatures and multiple different hematocrits, an alternating voltage is applied to the first electrode and the second electrode of multiple second test strips in a filled state at a predetermined frequency, and a second mutation test electrical signal between the first electrode and the second electrode of the multiple second test strips is acquired; Based on the multiple first mutation test electrical signals corresponding to each test condition, a first test mean corresponding to each test condition is obtained, and a first test mean set is constructed; Based on the multiple second mutation test electrical signals corresponding to each test condition, a second test mean corresponding to each test condition is obtained, and a second test mean set is constructed; Based on the first test mean set and the second test mean set, the preset threshold is determined.

5. The method according to claim 4, wherein Determining a preset threshold according to the first test mean set and the second test mean set includes: Determining a preset threshold according to the minimum value in the first test mean set and the maximum value in the second test mean set.

6. The method according to claim 5, wherein The determining a preset threshold according to the minimum value in the first test mean set and the maximum value in the second test mean set includes: Taking the average of the minimum value in the first test mean set and the maximum value in the second test mean set as the preset threshold.

7. The method according to claim 6, characterized in that, The taking the average of the minimum value in the first test mean set and the maximum value in the second test mean set as the preset threshold includes: Obtaining an average value according to the minimum value in the first test mean set and the maximum value in the second test mean set, and taking the value obtained by truncating the average value to two decimal places as the preset threshold.

8. The method according to claim 6, wherein The taking the average of the minimum value in the first test mean set and the maximum value in the second test mean set as the preset threshold includes: Obtaining an average value according to the minimum value in the first test mean set and the maximum value in the second test mean set, and taking the integer value of the average value as the preset threshold.

9. The method according to any one of claims 1 to 8, characterized in that, The first sample injection channel is located on the front side of the test strip, the second sample injection channel is located on the back side of the test strip, and the communication hole is a through hole penetrating the substrate of the test strip.

10. The method according to any one of claims 1 to 8, characterized in that, The first sample injection channel and the second sample injection channel are located on the same side of the test strip. A partition is provided between the second ends of the first sample injection channel and the second sample injection channel, and the communication hole is provided on the partition.

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