Array-type multi-channel sensing electrode and electrochemical detection method

Abstract

An array-type multi-channel sensing electrode and an electrochemical detection method. The array-type multi-channel sensing electrode comprises N columns of detection electrode groups and N / 2 or (N+1) / 2 reference electrodes, wherein each detection electrode group outputs a detection signal by means of a separate detection channel, each detection electrode group includes M detection electrodes, and one reference electrode is arranged between every two columns of detection electrode groups; and each detection electrode comprises one counter electrode and one working electrode, and the counter electrode is arranged around the working electrode. On the basis of different detection principles, different detection channels and different detection modes can be set to perform simultaneous detection on different substances to be subjected to detection, such that simultaneous and accurate detection can be realized even when there is a large variety of substances to be subjected to detection.

Description

Array multi-channel sensing electrode and electrochemical detection method Technical Field

[0001] The present application relates to the field of electrochemical detection technology, and in particular to an array-type multi-channel sensing electrode and an electrochemical detection method. Background Art

[0002] Commonly used material analysis technologies and detection methods include mass spectrometry, infrared spectroscopy, atomic fluorescence spectroscopy, etc. These technologies have high detection accuracy, but rely on large instruments and have the disadvantages of expensive equipment, cumbersome sample pretreatment steps, complex operations, and high costs.

[0003] Electrochemical analysis is low-cost, simple to operate, and easily integrated with back-end circuitry to create sensor systems. It has been widely used in the detection of various substances. However, when simultaneously detecting multiple substances, signal interference between the substances can cause the output signal to fail to accurately reflect the type and content of each substance when using a single method on a single electrode.

[0004] Summary of the Invention

[0005] The purpose of the present application is to provide an array-type multi-channel sensing electrode and an electrochemical detection method, which are used to solve the technical problem in the prior art of inaccurate electrochemical detection of the types and contents of multiple substances at the same time.

[0006] In a first aspect, embodiments of the present application provide an array-type multi-channel sensing electrode, the array-type multi-channel sensing electrode including N columns of detection electrode groups and N / 2 or (N+1) / 2 reference electrodes, each of the detection electrode groups outputting a detection signal through a separate detection channel, each of the detection electrode groups including M detection electrodes, where N is greater than or equal to 2, M is greater than or equal to 2, and N / 2 or (N+1) / 2 is an integer;

[0007] A reference electrode is provided between every two rows of detection electrode groups;

[0008] Each of the detection electrodes includes a counter electrode and a working electrode, and the counter electrode is arranged around the working electrode.

[0009] Optionally, the detection electrodes in each column of the detection electrode group are prepared using the same material or modified using the same sensitive material.

[0010] Optionally, the sensitive material modified on the electrode surface includes one or more of aptamers, antibodies, molecularly imprinted polymers, metal nanoparticles, metal oxides, MXene two-dimensional materials and their composites, metal organic frameworks and their composites, MoS2 and their composites, graphene and its composites, carbon nanotubes, other porous materials, etc.

[0011] Optionally, the detection electrode is made of any one of metal materials, conductive carbon paste, graphite, two-dimensional conductive materials, conductive polymers, and the like.

[0012] Optionally, the counter electrode is an unclosed circular ring; the working electrode is circular and is arranged in the circular ring.

[0013] Optionally, when each detection electrode group includes multiple detection electrodes, the multiple detection electrodes are connected in parallel or in series to the detection channel corresponding to the current detection electrode group.

[0014] In a second aspect, an embodiment of the present application further provides an electrochemical detection method, wherein the electrochemical detection method is performed using an array of multi-channel sensing electrodes, wherein the array of multi-channel sensing electrodes includes N columns of detection electrode groups, each detection electrode group outputting through a separate detection channel, and each detection electrode group including a reference electrode and M detection electrodes, wherein N is greater than or equal to 1, and M is greater than or equal to 2;

[0015] The method comprises:

[0016] Obtain the type of substance to be tested;

[0017] Matching a corresponding detection method and a corresponding number of detection electrode groups according to the type of the substance to be detected;

[0018] Acquiring a detection signal through the detection electrode group;

[0019] For each of the detection signals, a corresponding data analysis scheme is determined according to the detection method corresponding to the detection signal, and data analysis is performed on the detection signal according to the data analysis scheme to obtain a corresponding detection result.

[0020] Optionally, the detection method includes an electrochemical scanning method, a detection principle, and an electrode preparation and modification method.

[0021] Optionally, the step of matching a corresponding detection method and a corresponding number of detection electrode groups according to the type of the substance to be detected includes:

[0022] When there is more than one type of the substance to be detected, confirm whether there is a correlation between the types of each of the substances to be detected;

[0023] If there is no correlation between the substances to be detected, the detection electrode group and the detection method are set one-to-one for each substance to be detected.

[0024] Optionally, when there is more than one type of the substance to be detected, after the step of confirming whether there is a correlation between the types of the substances to be detected, the method further includes:

[0025] If any two or more of the substances to be detected are correlated, a detection electrode set and a detection method are matched according to the substances in the correlation to confirm the comprehensive concentration of the substances to be detected that are correlated;

[0026] The detection electrode group and the detection method are matched according to the substances to be detected with the correlation to confirm the individual concentration of each substance to be detected with the correlation, and the concentration of the remaining difficult-to-detect substances to be detected is confirmed based on the comprehensive concentration of the substances to be detected and the individual concentration.

[0027] Optionally, after the step of matching the detection electrode group and the detection method according to the substances to be detected with the correlation to confirm the individual concentration of each of the substances to be detected with the correlation, and confirming the concentration of the remaining difficult-to-detect substances to be detected based on the comprehensive concentration of the substances to be detected and the individual concentrations, the step further includes:

[0028] For the remaining irrelevant substances to be detected, the detection electrode group and the detection method are set one by one for each substance to be detected.

[0029] Optionally, if any two or more substances to be detected are correlated, the step of matching the detection electrode set and the detection method according to the substances in the correlation to confirm the comprehensive concentrations of the substances to be detected that are correlated includes:

[0030] Confirm the type of the substance to be detected that has the relevant relationship;

[0031] Determining the corresponding detection principle according to the type of the substance to be detected;

[0032] Determine the number of the corresponding detection electrode groups and the electrode preparation and modification method according to the detection principle;

[0033] The electrochemical scanning mode is determined according to the detection principle.

[0034] This solution proposes an array-type multi-channel sensing electrode, which includes N columns of detection electrode groups and N / 2 or (N+1) / 2 reference electrodes. Each detection electrode group outputs a detection signal through a separate detection channel. Each detection electrode group contains M detection electrodes. When using the array-type multi-channel sensing electrode to detect the concentration of a chemical substance, a user can match the corresponding detection method and the corresponding number of detection electrode groups according to the type of substance to be detected. Moreover, since each detection electrode group is in a different detection channel, the detection method of each detection electrode group can be set separately. Finally, the detection signal of each detection electrode group can be analyzed separately or comprehensively according to a data analysis scheme, thereby achieving simultaneous detection of different substances to be detected. Since whether the types of substances to be detected will affect each other is analyzed when matching the detection method, the appropriate detection method and data analysis scheme can be selected to ensure the accuracy of the final detection results for the type and content of each substance to be detected. Therefore, even when there are many types of substances to be detected, simultaneous and accurate detection can be achieved, thereby solving the technical problem of inaccurate electrochemical detection of multiple substances in the existing technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0036] FIG1 shows a schematic structural diagram of a four-channel parallel array electrode n=3 in an electrochemical detection method provided by the present invention;

[0037] FIG2 is a schematic diagram showing simulation results of cyclic voltammetric characteristics of electrodes with the number n of subunit arrays being 1, 2, and 3, respectively, in the electrochemical detection method provided by the present invention;

[0038] FIG3 shows a schematic structural diagram of various embodiments of array-type multi-channel sensing electrodes in the electrochemical detection method provided by the present invention;

[0039] FIG3-(A) shows a schematic structural diagram of a detection electrode group (i.e., an electrode assembly) in an array-type multi-channel sensing electrode having one channel, one detection electrode, and one reference electrode in the electrochemical detection method provided by the present invention;

[0040] FIG3-(B) shows a schematic diagram of the structure of an array-type multi-channel sensing electrode in an electrochemical detection method provided by the present invention, in which the number of channels is 2, the reference electrode is 1, the counter electrode is connected in parallel, and the number of detection electrodes is 1-n;

[0041] FIG3-(C) shows a schematic diagram of the structure of an array-type multi-channel sensing electrode in an electrochemical detection method provided by the present invention, in which there are 2 channels, 1 reference electrode, a counter electrode connected in series, and the number of detection electrodes is 1-n;

[0042] FIG4 shows a schematic structural diagram of an electrode obtained after modification with a sensitive material in the electrochemical detection method provided by the present invention;

[0043] FIG5 is a schematic diagram showing a flow chart of a first embodiment of an electrochemical detection method provided by the present invention;

[0044] FIG6 shows a schematic flow chart of a second embodiment of the electrochemical detection method provided by the present invention;

[0045] FIG7 is a schematic diagram showing the detection results of channel A in one embodiment of the electrochemical detection method provided by the present invention;

[0046] FIG8 is a schematic diagram showing the detection results of channel B in one embodiment of the electrochemical detection method provided by the present invention;

[0047] FIG9 is a schematic diagram showing the detection results of channel C in one embodiment of the electrochemical detection method provided by the present invention;

[0048] FIG10 is a schematic diagram showing the detection results of channel D in one embodiment of the electrochemical detection method provided by the present invention. DETAILED DESCRIPTION

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0050] The present application provides an array-type multi-channel sensing electrode. By setting up a multi-channel detection electrode group and matching the corresponding detection method and the corresponding number of detection electrode groups according to the type of substance to be detected, simultaneous and accurate detection can be achieved even when there are many types of substances to be detected, thereby solving the technical problem of inaccurate electrochemical detection of the types and contents of multiple substances in the existing technology.

[0051] The following is an analysis of the electrochemical detection solutions in the prior art in combination with relevant technologies.

[0052] In the prior art, when detecting substances, a single sensing electrode is generally used to detect the substance. This method can result in different detection results each time, and there is a problem of difficulty in ensuring consistency. When multiple substances are detected simultaneously through a single electrode, the output signal of the single electrode cannot accurately reflect the type and content of each substance. In particular, for substances with similar electrochemical properties, overlapping signal peak positions, or no signal peaks within the electrode potential window, the use of a single electrode for detection has many difficulties and limitations.

[0053] In one embodiment, referring to Figures 1 and 3, the present invention further provides an electrochemical detection device, wherein the array-type multi-channel sensing electrode includes N columns of detection electrode groups and N / 2 or (N+1) / 2 reference electrodes, each of the detection electrode groups outputs a detection signal through a separate detection channel, and each of the detection electrode groups includes M detection electrodes, wherein N is greater than or equal to 2, M is greater than or equal to 2, and N / 2 or (N+1) / 2 is an integer; a reference electrode is arranged between every two columns of the detection electrode groups; each of the detection electrodes includes 1 counter electrode and 1 working electrode, and the counter electrode is arranged around the working electrode.

[0054] At this time, when using the above-mentioned array multi-channel sensing electrode to detect the concentration of chemical substances, the corresponding detection method and the corresponding number of detection electrode groups can be matched according to the type of substance to be detected, and since each detection electrode group is in a different detection channel, the detection method of each detection electrode group can be set separately. Finally, the detection signal of each detection electrode group can be analyzed separately or comprehensively according to the data analysis plan, so as to realize the simultaneous detection of different substances to be detected. Since whether the types of substances to be detected will affect each other will be analyzed when matching the detection method, the appropriate detection method and data analysis plan can be selected to ensure the accuracy of the final detection results of the type and content of each substance to be detected, so that when there are many types of substances to be detected, simultaneous and accurate detection can be achieved, thereby solving the technical problem of inaccurate electrochemical detection of the types and contents of multiple substances in the existing technology.

[0055] Based on the above scheme, the electrochemical module of Comsol simulation software was used to simulate the cyclic voltammetric characteristics of sensing electrodes with array numbers n of 1, 2, and 3, respectively. The results are shown in Figure 2. The electrolytic cell simulated the environment with a 5mM potassium ferrocyanide solution, and the working electrode peak currents were 7.27μA, 14.82μA, and 22.32μA, respectively. The above experiments show that there is a geometric relationship between the array number and the working electrode peak current. Each electrode can determine the detection value based on the average value. Therefore, increasing the array number can lead to more stable and accurate detection results.

[0056] In an optional manner, the detection electrodes in each column of the detection electrode group are prepared using the same material or modified using the same sensitive material.

[0057] In this case, using different surface-modified sensitive materials is intended to achieve specific recognition, thereby accurately detecting the concentration and type of substance. Using the same material or modifying the same sensitive material within a column allows for weighted averaging, resulting in more stable and accurate detection results. This avoids detection errors caused by uneven modification of individual electrodes.

[0058] In an optional manner, the sensitive material for modifying the electrode surface includes one or more of aptamers, antibodies, molecularly imprinted polymers, metal nanoparticles, metal oxides, MXene two-dimensional materials and their composites, metal organic frameworks and their composites, MoS2 and their composites, graphene and its composites, carbon nanotubes, other porous materials, etc.

[0059] In an optional manner, the detection electrode is prepared from any one of metal materials, conductive carbon paste, graphite, two-dimensional conductive materials, conductive polymers, and the like.

[0060] Among them, the metal material can be gold, platinum, titanium, etc.

[0061] In an optional manner, the substrate material of the detection electrode may be any one or more combinations of: silicon wafer, glass sheet, circuit board, paper base, and plastic.

[0062] In an optional manner, when each detection electrode group includes a plurality of detection electrodes, the pairs of electrodes in the plurality of detection electrodes are connected in parallel or in series.

[0063] During actual detection, the detection signal output by each channel can be calculated according to the principle of parallel or series electrical signals to obtain the detection signal on each detection electrode. Since the final data obtained in parallel or series is an average value, it can avoid inaccurate detection caused by an error in a certain detection electrode, and can also average the detection error, making the final detection result more accurate.

[0064] In an optional manner, the counter electrode is an unclosed circular ring; the working electrode is circular and is arranged in the circular ring.

[0065] The working electrode may also be circular, rectangular, triangular, polygonal, etc.

[0066] In an optional manner, the counter electrode is an unclosed circular ring with a radius of 2 mm; the working electrode is circular and arranged in the circular ring with a radius of 1 mm; the reference electrode has a radius of 1.5 mm.

[0067] Through the above arrangement, it can be ensured that each electrode can achieve good detection and be isolated from each other. The small size arrangement can more conveniently increase the number of working electrodes and reference electrodes when needed.

[0068] According to another aspect of the embodiments of the present invention, the present application also proposes an electrochemical detection method. FIG5 shows a flow chart of a first embodiment of the electrochemical detection method of the present invention. The electrochemical detection method performs detection through an array multi-channel sensing electrode. As shown in FIG3 , the array multi-channel sensing electrode includes N columns of detection electrode groups, each detection electrode group outputs through a separate detection channel, and each detection electrode group includes a reference electrode and M detection electrodes, where N is greater than or equal to 1 and M is greater than or equal to 2. As shown in FIG5 , the method includes the following steps:

[0069] The method comprises:

[0070] Step S1, obtaining the type of substance to be detected;

[0071] The types of substances to be detected may be various substances that can be detected by electrochemical detection methods.

[0072] Step S2, matching a corresponding detection method and a corresponding number of detection electrode groups according to the type of the substance to be detected;

[0073] In an optional manner, the detection method includes an electrochemical scanning method, a detection principle, and an electrode preparation and modification method.

[0074] Among them, electrode preparation and modification methods include the following categories:

[0075] Changes in sensor electrode preparation methods: screen printing, micro-nano processing, inkjet printing, etc.

[0076] Changes in electrode material composition: metal materials (gold, platinum, titanium, etc.), conductive carbon paste, graphite, etc.;

[0077] Changes in electrode substrate materials: silicon wafers, glass wafers, circuit boards, paper substrates, plastics, etc.;

[0078] Changes in electrode structure: circular, rectangular, triangular, polygonal, etc.;

[0079] Changes in electrode dimensions: the area of ​​the working electrode, counter electrode, and reference electrode, the spacing between array electrodes, the number and distance of channels, etc. The above can be selected by the user according to actual needs, and the detailed scheme will not be described here.

[0080] At this time, the number of detection methods also matches the number of types of substances to be detected. The specific process is as follows:

[0081] In an optional manner, as shown in FIG6 , the step of matching a corresponding detection method and a corresponding number of detection electrode groups according to the type of the substance to be detected includes:

[0082] Step S21: when there is more than one type of the substance to be detected, confirm whether there is a correlation between the types of the substances to be detected;

[0083] Among them, when the substances to be detected are two or more different substances, the two substances to be detected may have similar detection principles, that is, the common content of the two or more substances to be detected can be detected by one detection method, then it is determined that there is a correlation between these substances.

[0084] Step S22: If there is no correlation between the substances to be detected, the detection electrode group and the detection method are set one-to-one for each substance to be detected.

[0085] In the above steps, it is only necessary to match the corresponding number of detection electrode groups and the corresponding detection method according to the known types of substances to be detected. For possible substances to be detected, the number of detection electrode groups required for each substance to be detected and the corresponding detection method are pre-set. For example, when the substance to be detected is methamphetamine, the preset corresponding detection principle can be oxidation peak detection and specific detection, the electrochemical scanning method is differential pulse voltammetry, and the electrode preparation modification method includes the number of detection electrode groups being 1 and the electrode pre-treatment scheme. The detection method of other types of substances to be detected is pre-set with reference to the above settings and the specific scheme is improved.

[0086] Optionally, when there is more than one type of the substance to be detected, after the step of confirming whether there is a correlation between the types of the substances to be detected, the method further includes:

[0087] Step S23: If any two or more of the substances to be detected are correlated, matching the detection electrode set and the detection method according to the substances in the correlation to determine the comprehensive concentrations of the substances to be detected that are correlated;

[0088] When the number of substances to be detected that are correlated is L, the common content of the L substances to be detected needs to be detected using the same detection principle.

[0089] Step S24, matching the detection electrode group and the detection method according to the substances to be detected with the correlation to confirm the individual concentration of each substance to be detected with the correlation, and confirming the concentration of the remaining difficult-to-detect substances to be detected based on the comprehensive concentration of the substances to be detected and the individual concentrations.

[0090] In the above embodiment, the combined content of L related test substances is first detected using one detection principle. The test substances are then individually detected using L-1 other detection principles to determine the content of the L-1 test substances, thereby determining the content of the remaining test substance. This approach can be used when the test substances are related and it is difficult to detect a single substance individually, thereby allowing for more accurate determination of the content of each test substance. L is greater than or equal to 2.

[0091] Optionally, after the step of matching the detection electrode group and the detection method according to the substances to be detected with the correlation to confirm the individual concentration of each of the substances to be detected with the correlation, and confirming the concentration of the remaining difficult-to-detect substances to be detected based on the comprehensive concentration of the substances to be detected and the individual concentrations, the step further includes:

[0092] Step S25 , setting the detection electrode group and the detection method for each of the remaining irrelevant substances to be detected one by one.

[0093] The detection mode setting at this time refers to the setting mode in step S22.

[0094] In the present application, the above-mentioned scheme can be used to detect substances with related relationships, avoiding the situation where there are too many detection methods for the substances to be detected and they cannot be effectively matched. It can also solve the situation where the substances to be detected are relatively similar and the only available detection method overlaps with the detection methods of other substances to be detected, thereby achieving accurate detection.

[0095] Step S3, obtaining a detection signal through the detection electrode group;

[0096] The detection signal is expressed in the form of an electrical signal, and each detection electrode group can be individually detected to obtain the electrical signal.

[0097] Step S4: for each of the detection signals, determine a corresponding data analysis scheme according to the detection method corresponding to the detection signal, and perform data analysis on the detection signal according to the data analysis scheme to obtain a corresponding detection result.

[0098] Among them, the corresponding detection method and the corresponding number of detection electrode groups are matched according to the type of the substance to be detected. Each detection electrode group is in a different detection channel, so that the detection method of each detection electrode group can be set separately. Finally, the detection signal of each detection electrode group can be analyzed separately or comprehensively according to the data analysis plan, so as to realize the simultaneous detection of different substances to be detected. Since whether the types of substances to be detected will affect each other will be analyzed when matching the detection method, the appropriate detection method and data analysis plan can be selected to ensure the accuracy of the final detection results of the type and content of each substance to be detected, so that when there are many types of substances to be detected, simultaneous and accurate detection can be achieved, thereby solving the technical problem of inaccurate electrochemical detection of the types and contents of multiple substances in the existing technology.

[0099] It should be noted that, since the electrochemical detection method of the present application can implement all embodiments of the array multi-channel sensing electrode, the electrochemical detection method of the present application has all the beneficial effects of the array multi-channel sensing electrode, which will not be described in detail here.

[0100] In an optional manner, when there are multiple detection electrodes in each group, the multiple detection electrodes are connected in parallel or in series to the detection channel corresponding to the current detection electrode group.

[0101] At this time, obtaining the detection results by parallel or series connection can avoid the error of a single detection electrode. By weighting and averaging the detection signals output by the channels in parallel or series connection, the accuracy of the detection results can be improved, and the repeatability and consistency of the sensor can be improved.

[0102] Refer to Figure 3, wherein Figure 3 shows a schematic structural diagram of various embodiments of the array-type multi-channel sensing electrode in the electrochemical detection method provided by the present invention; Figure 3-(A) shows a schematic structural diagram of a detection electrode group (i.e., an electrode assembly) in which the array-type multi-channel sensing electrode in the electrochemical detection method provided by the present invention has 1 channel, 1 detection electrode, and 1 reference electrode; Figure 3-(B) shows a schematic structural diagram of a detection electrode group (i.e., an electrode assembly) in which the array-type multi-channel sensing electrode in the electrochemical detection method provided by the present invention has 2 channels, 1 reference electrode, 1 counter electrode connected in parallel, and 1 detection electrode. A schematic structural diagram of a pole number of 1-n, that is, a dual-channel parallel array electrode, wherein 3-(B)-(a) to 3-(B)-(d) are structural diagrams of a number of series electrodes of 1-n; Figure 3-(C) shows a structural schematic diagram of an array-type multi-channel sensing electrode in an electrochemical detection method provided by the present invention, in which the channel is 2, the reference electrode is 1, the counter electrode is connected in series, and the number of detection electrodes is 1-n, that is, a dual-channel series array electrode, wherein 3-(C)-(a) to 3-(C)-(d) are structural diagrams of a number of series electrodes of 1-n.

[0103] In the above embodiment, the array design of the array multi-channel sensing electrode utilizes the superposition of multiple sensor signals and improves the accuracy of the detection results and the repeatability and consistency of the sensor by weighting and averaging the response values. As shown in Figure 2B-d, taking a dual-channel parallel array electrode comprising n groups of sub-unit arrays as an example, the total output current value Io of each sensing channel is the superposition of the current response values ​​of each working electrode, that is, I o =I1+I2+I3+…+I n

[0104] The average effective current value Ieff of each working electrode is:

[0105] The use of arrayed multi-channel sensing electrodes and electrochemical analysis methods can achieve simultaneous detection of multiple substances.

[0106] In an optional manner, if any two or more of the substances to be detected are correlated, the step of matching the detection electrode set and the detection method according to the substances in the correlation to confirm the comprehensive concentration of the substances to be detected that have the correlation includes:

[0107] Confirm the type of the substance to be detected that has the relevant relationship;

[0108] Correlation means that if the common content of two or more substances to be detected can be detected by the detection principle of one detection method, it is determined that there is a correlation between these substances.

[0109] Determining the corresponding detection principle according to the type of the substance to be detected;

[0110] When there are L types of substances to be detected that are correlated, it is necessary to detect the common content of the L substances to be detected through one detection principle, and then detect the individual content of L-1 substances to be detected separately through other detection principles, so as to determine the content of the remaining substance to be detected. This method can be used to detect situations where the substances to be detected are related and it is difficult to detect a certain substance alone, so that the content of each substance to be detected can be detected more clearly. L is greater than or equal to 2. It should be noted that at this time, it is necessary to ensure that the L-1 other substances to be detected include at least two detection principles.

[0111] In order to fully guarantee the smooth implementation of this scheme, it is necessary to ensure that, in addition to the same detection principle, the L-1 other substances to be detected also need to include a detection principle that is different from the detection principle of the other substances to be detected.

[0112] Determine the number of the corresponding detection electrode groups and the electrode preparation and modification method according to the detection principle;

[0113] The electrochemical scanning mode is determined according to the detection principle.

[0114] Through the above scheme, the actual content of the substances to be detected with correlation can be detected, ensuring that the actual content of each substance to be detected can be clearly detected under the same detection principle.

[0115] The following is an example of a process for detecting the content of morphine, heroin, tetrahydrocannabinol, ketamine, methamphetamine, cocaine, and amphetamine in a solution:

[0116] By identifying the substances, it was determined that there was no correlation between morphine, heroin, tetrahydrocannabinol, and ketamine. Therefore, they could be detected separately based on the different positions of their oxidation peaks. However, to determine if there was a correlation between methamphetamine, cocaine, and amphetamine, it was necessary to detect each substance individually to determine their levels. Therefore, a three-array, four-channel electrode was selected for detection. Channel A utilizes the redox principle to detect morphine, heroin, tetrahydrocannabinol, and ketamine. Channels B, C, and D, each modified with a different sensitive material, were used to detect methamphetamine, cocaine, and amphetamine, respectively. A corresponding scanning method, such as differential pulse voltammetry, was then selected to obtain the detection signal. The possible detection results are shown in Figures 7-10. Figure 7 shows the output of Channel A: simultaneous detection of morphine, heroin, tetrahydrocannabinol, and ketamine. When the target substances are present in the solution, oxidation peaks corresponding to each substance appear when scanning using differential pulse voltammetry. Figure 8 shows the output of Channel B: detection of methamphetamine. When methamphetamine is present, the background current value of the marker in the solution decreases. Figure 9 shows the output of Channel C: detection of cocaine. When cocaine is present, the background current value of the marker in the solution decreases. Figure 10 shows the output of Channel D: detection of amphetamine. When amphetamine is present, the background current value of the marker in the solution decreases.

[0117] In an optional manner, when there are two types of substances to be detected, and the two substances to be detected are methamphetamine and amphetamine, respectively, the step of determining the corresponding detection principle according to the type of the substances to be detected further includes:

[0118] The detection principle matched with the methamphetamine and the amphetamine is an oxidation peak detection principle and a specific aptamer recognition principle.

[0119] The oxidation peak detection principle is a method for identifying oxidation peaks, and the specific aptamer recognition principle is a method for identifying and capturing methamphetamine and amphetamine.

[0120] Specifically, with reference to shown in Figure 4, the reason being applied in above-mentioned detection is: methamphetamine (methamphetamine, METH) and amphetamine (amphetamine, AMP) belong to amphetamine substances together, have similar structure and property.METH and AMP can be identified and captured by same specific aptamer, but they are different from the binding ability of aptamer. Taking a kind of aptamer (aptamer, APT) commonly used as example, its base sequence is 5 '-(HS)-(CH2)6-ACGGTTGCAAGTGGGACTCTGGTAGGCTGGGTTAATTTGG-3 ', the current response change caused by this aptamer after in conjunction with methamphetamine is greater than the response change caused in conjunction with amphetamine.Amphetamine does not have redox characteristic in the potential window of electrode, and methamphetamine is electroactive substance, and it has oxidation peak near 1V.

[0121] In an optional manner, the step of determining the number of the corresponding detection electrode groups and the electrode preparation and modification method according to the detection principle further includes:

[0122] Based on the oxidation peak detection principle and the specific aptamer recognition principle for detecting the concentration of the methamphetamine and the amphetamine, the number of the detection electrode groups is 2, including a first detection electrode group (channel A) and a second detection electrode group (channel B), the second detection electrode (channel B) group is used for detecting by the specific aptamer recognition principle, and the first detection electrode group (channel A) is used for detecting by the oxidation peak detection principle;

[0123] For the second detection electrode group (channel B), a new methylene blue suspension of a first concentration is drop-coated on the surface of each electrode of the second detection electrode group, and then dried at room temperature for a first preset time to obtain a second detection electrode group modified with a first sensitive material;

[0124] The first concentration can be set to 1 mg / mL. At this time, the amount of drop coating is 20 μL of New Methylene Blue (NMB) suspension. The first preset time is 12 h, and the obtained modified electrode is NMB MCAE.

[0125] Preparing a nano-gold deposition solution of a second concentration, and depositing the nano-gold on the surface of each electrode of the second detection electrode group for a second preset time period by chronoamperometry to obtain a second detection electrode group modified with a second sensitive material;

[0126] Among them, the second concentration can be set to 6mmol / L, which can be obtained by diluting a 1% chloroauric acid (HAuCl4) solution with 0.5mol / L dilute sulfuric acid. The second preset time can be set to 120s, and the second specific aptamer is AuNPs / NMB MCAE. That is, the chronoamperometry method is used to electro-deposit gold nanoparticles on the NMB MCAE surface of channel B, with a deposition potential of -0.2V and a deposition time of 120s to obtain AuNPs / NMB MCAE.

[0127] A specific recognition aptamer (APT) was added to the surface of each electrode of the second detection electrode group (channel B), and the excess active sites on the surface of each electrode were blocked with mercaptohexanol. The electrodes were dried at 4°C for 24 h to obtain sensing electrodes modified with APT / AuNPs / NMB MCAE.

[0128] By using the above electrode preparation and modification method, a detection electrode group that can be used for detection is prepared.

[0129] In an optional manner, the step of determining the electrochemical scanning mode according to the detection principle includes:

[0130] When the detection method is the oxidation peak detection principle and the specific aptamer recognition principle, the detection is performed by electrochemical scanning;

[0131] The electrochemical scanning method confirmed is differential pulse voltammetry;

[0132] Obtaining oxidation peak detection results through the first detection electrode group (channel A);

[0133] The concentration of the oxidation peak detection result obtained at this time is the concentration of methamphetamine.

[0134] The mixed concentration of amphetamine substances recognized by the specific aptamer is detected by the second detection electrode group.

[0135] In an optional manner, for each of the detection signals, determining a corresponding data analysis scheme according to the detection method corresponding to the detection signal, and performing data analysis on the detection signal according to the data analysis scheme to obtain a corresponding detection result includes:

[0136] When the detection method is the oxidation peak detection principle and the specific aptamer recognition principle, data analysis is performed using the first concentration analysis scheme;

[0137] If the oxidation peak detection result of the first detection electrode group determines that there is no oxidation peak, then the solution to be detected does not contain methamphetamine and may contain amphetamine;

[0138] If the oxidation peak detection result of the first detection electrode group determines that an oxidation peak exists, determining the concentration of the methamphetamine according to the oxidation peak detection result;

[0139] The concentration of the amphetamine is determined according to the mixed concentration of the amphetamine-like substances and the concentration of the methamphetamine.

[0140] In the above embodiment, assuming that the concentration of methamphetamine in the solution is c1 and the concentration of amphetamine is c2, and the concentration of amphetamine-like substances measured by the second detection electrode group (channel B) is defined as call, the following relationship exists: C all =f(c1,c2)

[0141] Ideally, there is C all =αc1+βc2

[0142] When determining the calibration curve in the standard sample, the values ​​of the functional relationship f or α and β can be determined based on the known c1 and c2 values ​​and the measured call; during actual detection, the methamphetamine concentration c1 can be calculated based on the results of the first detection electrode group (channel A), and the amphetamine-like substance concentration call can be calculated based on the second detection electrode group (channel B), and the amphetamine concentration c2 can be inferred using the standard curve.

[0143] The algorithms or displays provided herein are not inherently related to any particular computer, virtual system or other device. In addition, the embodiments of the present invention are not directed to any particular programming language.

[0144] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the present invention may be practiced without these specific details. Similarly, in order to streamline the present invention and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of embodiments of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. The claims that follow the detailed description are hereby expressly incorporated into that detailed description, with each claim itself serving as a separate embodiment of the present invention.

[0145] Those skilled in the art will appreciate that the modules in the devices of the embodiments can be adaptively changed and installed in one or more devices different from the embodiments. The modules, units, or components in the embodiments can be combined into one module, unit, or component, and furthermore, they can be divided into multiple submodules, subunits, or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive.

[0146] It should be noted that the above embodiments illustrate rather than limit the invention, and that alternative embodiments may be devised by a person skilled in the art without departing from the scope of the appended claims. In the claims, any reference signs placed between brackets should not be construed as limiting the claims. The word "" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising several different elements and by means of appropriately programmed computers. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third etc. does not indicate any order. These words may be interpreted as names. The steps in the above embodiments should not be understood as limiting the order of execution unless otherwise specified.

Claims

1. An array-type multi-channel sensing electrode, characterized in that, The array multi-channel sensing electrode includes N columns of detection electrode groups and N / 2 or (N + 1) / 2 reference electrodes. Each detection electrode group outputs a detection signal through a separate detection channel, and each detection electrode group contains M detection electrodes, where N is greater than or equal to 2, M is greater than or equal to 2, and N / 2 or (N + 1) / 2 is an integer; One reference electrode is arranged between every two columns of the detection electrode groups; Each detection electrode includes 1 counter electrode and 1 working electrode, and the counter electrode is arranged around the working electrode.

2. The array-type multi-channel sensing electrode according to claim 1, characterized in that, The detection electrodes in each column of the detection electrode groups are prepared using the same material or modified using the same sensitive material.

3. The array-type multi-channel sensing electrode according to claim 2, characterized in that, The sensitive materials modified on the electrode surface include one or more of aptamers, antibodies, molecularly imprinted polymers, metal nanoparticles, metal oxides, MXene two-dimensional materials and their composites, metal-organic frameworks and their composites, MoS2 and its composites, graphene and its composites, carbon nanotubes, other porous materials, etc.

4. The array-type multi-channel sensing electrode according to claim 2, characterized in that, The preparation material of the detection electrode is any one of metal materials, conductive carbon paste, graphite, two-dimensional conductive materials, conductive polymers, etc.

5. The array-type multi-channel sensing electrode according to claim 1, characterized in that, The counter electrode is an unclosed ring; the working electrode is circular and is arranged in the ring; the working electrode can also be: rectangular, triangular, polygonal, etc.

6. The electrochemical detection method according to claim 1, characterized in that, When the number of detection electrodes in each detection electrode group is multiple, the counter electrodes in the multiple detection electrodes are connected in parallel or in series.

7. An electrochemical detection method, characterized in that, The electrochemical detection method is performed by using the array multi-channel sensing electrode according to any one of claims 1-6. The array multi-channel sensing electrode includes N columns of detection electrode groups, and each detection electrode group outputs through a separate detection channel. Each detection electrode group contains a reference electrode and M detection electrodes, where N is greater than or equal to 1 and M is greater than or equal to 2; The method includes: Obtaining the type of the substance to be detected; Matching the corresponding detection method and the corresponding number of detection electrode groups according to the type of the substance to be detected; Obtaining a detection signal through the detection electrode group; For each detection signal, determining a corresponding data analysis scheme according to the detection method corresponding to the detection signal, and performing data analysis on the detection signal according to the data analysis scheme to obtain a corresponding detection result.

8. The electrochemical detection method according to claim 7, characterized in that, The detection methods include electrochemical scanning methods, detection principles, and electrode preparation and modification methods.

9. The electrochemical detection method according to claim 7, characterized in that, The step of matching the corresponding detection method and the corresponding number of detection electrode groups according to the type of the substance to be detected includes: When the types of the substances to be detected exceed one, confirming whether there is a correlation between the types of each substance to be detected; If there is no correlation between the substances to be detected, setting the detection electrode group and the detection method for each substance to be detected one by one.

10. The electrochemical detection method according to claim 7, characterized in that, After the step of confirming whether there is a correlation between the types of each substance to be detected when the types of the substances to be detected exceed one, it further includes: If there is a correlation among any two or more of the substances to be detected, match a detection electrode group and the detection method according to the substances in the correlation to confirm the comprehensive concentration of the substances to be detected with the correlation; Match the detection electrode group and the detection method according to the substances to be detected with the correlation to confirm the individual concentration of each substance to be detected with the correlation, and confirm the concentration of the remaining substances to be detected that are difficult to detect according to the comprehensive concentration and the individual concentration of the substances to be detected. After the step of matching the detection electrode group and the detection method according to the substances to be detected with the correlation to confirm the individual concentration of each substance to be detected with the correlation, and confirming the concentration of the remaining substances to be detected that are difficult to detect according to the comprehensive concentration and the individual concentration of the substances to be detected, the following steps are further included:

11. The electrochemical detection method according to claim 10, characterized in that, Set the detection electrode group and the detection method for each of the remaining substances to be detected that are not correlated one by one; The step of, if there is a correlation among any two or more of the substances to be detected, matching a detection electrode group and the detection method according to the substances in the correlation to confirm the comprehensive concentration of the substances to be detected with the correlation includes:

12. The electrochemical detection method according to claim 10, characterized in that, Confirm the types of the substances to be detected with the correlation; Determine the corresponding detection principle according to the types of the substances to be detected; Determine the number of the corresponding detection electrode groups and the electrode preparation and modification method according to the detection principle; Determine the electrochemical scanning method according to the detection principle. ​

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