Electrochemical analysis detection device and control method

Abstract

The invention provides an electrochemical analysis and detection device and a control method. An index to be detected is obtained through an input and output module; the core control module controls the input signal generation module to generate an excitation signal according to the to-be-detected index; the potential of the electrode module is controlled through the constant potential module according to the excitation signal; an electrode module and a to-be-detected sample are subjected to electrochemical reaction, and a first current response signal is generated; the electrode module and a sample to be detected are accommodated in the electrolytic tank, and an electrochemical reaction place is provided; sampling and converting the excitation signal and the first current response signal through a signal conversion module to generate a digital signal; and generating a first detection result through the core control module according to the digital signal and the excitation signal. The control logics of various electrochemical detection methods are integrated on the same set of hardware, different indexes can be detected through simple operation, the use threshold and the manufacturing cost of the electrochemical analyzer are reduced, and the electrochemical analyzer can be widely applied to the technical field of electrochemical analysis.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrochemical detection, and in particular relates to an electrochemical analysis detection device and a control method. Background Art

[0002] According to data from the World Health Organization (WHO) and the International Agency for Research on Cancer (IARC), there will be approximately 20 million new cancer cases and 9.7 million deaths worldwide in 2022. Nearly 2 billion people worldwide suffer from anemia, accounting for about 25% of the world's population, with the highest proportion of children and women of childbearing age in Africa (67.6%). It is considered a global health problem affecting developed and developing countries. Early disease screening is an important part of modern preventive medicine and plays a significant role in improving disease cure rates and reducing mortality. ctDNA can be used as a blood biopsy marker and plays an important role in the early diagnosis, efficacy monitoring and prognosis evaluation of malignant tumors.

[0003] Compared with traditional disease detection methods such as optics, mass spectrometry and immunoassay, electrochemical detection methods have many advantages: first, in terms of sensitivity, electrochemical detection methods can achieve detection limits of pM or even fM, and can effectively capture trace biomarker changes in the early stages of the disease; second, in terms of specificity, electrochemical detection methods can still effectively distinguish target substances in complex samples (such as blood), without the need for cumbersome pre-treatment steps, and have strong anti-interference capabilities; third, in terms of detection speed, results are usually obtained in just a few minutes to tens of minutes, which can well meet the needs of immediate diagnosis; finally, in terms of wide applicability, electrochemical methods are not only suitable for virus detection, but can also be used for the detection of bacteria, tumor markers and other diseases. Its flexibility and adaptability enable it to meet the diagnostic needs of different types of diseases.

[0004] The potentiostat is a key instrument for performing electrochemical detection methods such as voltammetry and electrochemical impedance spectroscopy. Unfortunately, laboratory-grade potentiostats are generally bulky, difficult to transport to remote areas, and very expensive. These two factors make laboratory-grade potentiostats unsuitable for use in resource-limited areas. Summary of the invention

[0005] The purpose of the present invention is to solve one of the technical problems existing in the prior art to at least a certain extent.

[0006] To this end, one purpose of an embodiment of the present invention is to provide an electrochemical analysis and detection device, which integrates the control logic of multiple electrochemical detection methods on the same set of hardware, and completes the detection tasks of different indicators by simply replacing electrodes and setting detection indicators. It is simple to operate, portable and economical, and reduces the use threshold and manufacturing cost of electrochemical analyzers.

[0007] The first technical solution adopted by the present invention is:

[0008] An electrochemical analysis detection device, characterized in that it includes an input and output module, a core control module, an input signal generation module, a constant potential module, an electrode module, an electrolytic cell and a signal conversion module, wherein the input and output module, the input signal generation module and the signal conversion module are all connected to the core control module, the input signal generation module, the electrode module, the electrolytic cell and the signal conversion module are all connected to the constant potential module, the signal conversion module and the electrode module are all connected to the electrolytic cell, the input and output module is used to obtain an indicator to be detected, the core control module is used to control the input signal generation module to generate an excitation signal according to the indicator to be detected, the constant potential module is used to control the potential of the electrode module according to the excitation signal, the electrode module is used to perform an electrochemical reaction with a sample to be detected to generate a first current response signal, the electrolytic cell is used to accommodate the electrode module and the sample to be detected and provide an electrochemical reaction site, the signal conversion module is used to sample and convert the excitation signal and the first current response signal to generate a digital signal, and the core control module is also used to generate a first detection result according to the digital signal and the excitation signal.

[0009] Furthermore, the indicator to be detected is one of circulating tumor gene concentration, hematocrit and hydrogen ion concentration.

[0010] Furthermore, the excitation signal is one of a cyclic square wave voltage signal, an AC excitation signal and a zero potential signal.

[0011] Furthermore, the electrode module includes a gold electrode, a silver chloride electrode, a platinum sheet electrode and a hydrogen ion selective electrode.

[0012] Furthermore, the signal conversion module includes a synchronous sampling submodule, a current-voltage conversion submodule, an analog-to-digital converter and a synchronous sampling analog-to-digital converter, and the digital signal includes a digital response signal and a synchronous sampling digital response signal.

[0013] Further, the hydrogen ion selective electrode is prepared by the following steps:

[0014] Selecting a commercial metal electrode as a base electrode and pretreating the commercial metal electrode;

[0015] The polyaniline conductive intermediate film solution is prepared by using aniline monomer, ammonium persulfate, polyvinyl alcohol and sulfuric acid solution;

[0016] An ion-sensitive membrane solution is prepared by using cyclohexanone, dioctyl sebacate, potassium tetrakis(4-chlorophenyl)borate, carboxypolyvinyl chloride and hydrogen ion carrier;

[0017] Applying the polyaniline conductive intermediate film solution on the surface of the commercial metal electrode to form a conductive intermediate layer;

[0018] The ion-sensitive membrane solution is coated on the surface of the conductive intermediate layer to form a sensitive membrane layer, thereby obtaining the hydrogen ion selective electrode.

[0019] Further, the index to be detected is the circulating tumor gene concentration, and the second detection result is obtained by the following steps:

[0020] Controlling the input signal generation module to generate the cyclic square wave voltage signal through the core control module;

[0021] Using the gold electrode as a working electrode, the silver chloride electrode as a reference electrode and the platinum electrode as a counter electrode;

[0022] Controlling the potentials of the gold electrode and the silver chloride electrode according to the cyclic square wave voltage signal by the constant potential module;

[0023] generating the second current response signal through the gold electrode;

[0024] converting the second current response signal into a first voltage response signal by the current-voltage conversion submodule;

[0025] converting the first voltage response signal into a first digital response signal by the analog-to-digital converter;

[0026] The core control module draws a voltammetric curve according to the first digital response signal and the cyclic square wave voltage signal, and calculates the relationship between the peak current in the voltammetric curve and the circulating tumor gene concentration through a preset first fitting model to obtain the second detection result.

[0027] Further, the indicator to be detected is the hematocrit, and the third test result is obtained by the following steps:

[0028] Controlling the input signal generation module to generate the AC excitation signal through the core control module;

[0029] Using the gold electrode as a working electrode, the silver chloride electrode as a reference electrode and the platinum sheet electrode as a counter electrode;

[0030] Controlling the potentials of the gold electrode and the silver chloride electrode according to the AC excitation signal by the constant potential module;

[0031] generating the third current response signal through the gold electrode;

[0032] converting the third current response signal into the second voltage response signal through the current-voltage conversion submodule;

[0033] Acquiring the amplitude and phase of the AC excitation signal and the second voltage response signal through the synchronous sampling submodule;

[0034] Converting the amplitude and phase of the AC excitation signal and the second voltage response signal into the synchronous sampling digital response signal through the synchronous sampling analog-to-digital conversion submodule;

[0035] The core control module draws an impedance spectrum curve according to the synchronously sampled digital response signal, and calculates the relationship between the impedance spectrum curve and the hematocrit according to a preset second fitting model to obtain the third detection result.

[0036] Further, the indicator to be detected is the hydrogen ion concentration, and the fourth detection result is obtained by the following steps:

[0037] Controlling the input signal generating module to generate the zero potential signal through the core control module;

[0038] using the hydrogen ion selective electrode as a working electrode and the silver chloride electrode as a reference electrode;

[0039] Controlling the potentials of the hydrogen ion selective electrode and the silver chloride electrode according to the zero potential signal by the constant potential module;

[0040] using the open circuit potential between the hydrogen ion selective electrode and the silver chloride electrode as the fourth current response signal;

[0041] Converting the fourth current response signal into a third voltage response signal through the current-voltage conversion submodule;

[0042] converting the third voltage response signal into a second digital response signal by the analog-to-digital converter;

[0043] The core control module calculates the relationship between the second digital response signal and the hydrogen ion concentration according to a preset third fitting model to obtain the fourth detection result.

[0044] The second technical solution adopted by the present invention is:

[0045] A control method for an electrochemical analysis detection device, which is implemented by the above-mentioned electrochemical analysis detection device, comprises the following steps:

[0046] Obtaining the indicator to be detected through the input and output module;

[0047] Controlling the input signal generation module to generate an excitation signal according to the indicator to be detected by the core control module;

[0048] Controlling the potential of the electrode module according to the excitation signal by the constant potential module;

[0049] The electrode module performs an electrochemical reaction with the sample to be tested to generate a first current response signal;

[0050] The electrolytic cell accommodates the electrode module and the sample to be tested, providing a place for electrochemical reaction;

[0051] The signal conversion module samples and converts the excitation signal and the first current response signal to generate a digital signal;

[0052] A first detection result is generated by the core control module according to the digital signal and the excitation signal.

[0053] The beneficial effects of the present invention are as follows: the present invention integrates the control logic of three electrochemical detection methods, namely cyclic voltammetry, electrochemical impedance spectroscopy and open circuit potential method, on the same set of hardware, and can complete the detection task of different indicators by simply replacing electrodes and setting detection indicators. The operation is simple, portable and economical, and the use threshold and manufacturing cost of the electrochemical analyzer are reduced; at the same time, the present invention further reduces the manufacturing cost of the device by designing a preparation method of a low-cost hydrogen ion selective electrode; in addition, the scope of the detection content of the present invention covers early cancer screening (ctDNA), blood health (HCT) and acid-base balance (pH), and can be widely used in a variety of environments, especially in areas with limited resources, and can perform rapid and effective early screening of diseases, thereby improving public health monitoring capabilities and providing possibilities for early intervention and treatment, thereby helping to improve patient prognosis and reduce medical costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A schematic diagram of the structure of an electrochemical analysis detection device provided by an embodiment of the present invention;

[0055] Figure 2 A comparison chart of cyclic voltammetry test curves of an electrochemical analysis detection device provided by an embodiment of the present invention and a conventional device;

[0056] Figure 3 Schematic diagram of a selected commercial three-electrode provided for an embodiment of the present invention;

[0057] Figure 4 A schematic diagram of the structure of a modified hydrogen ion selective electrode provided in an embodiment of the present invention;

[0058] Figure 5A comparison diagram of electrochemical impedance spectroscopy provided by an embodiment of the present invention;

[0059] Figure 6 A curve comparison diagram of the detection results of cyclic square wave voltammetry of an electrochemical analysis detection device provided by an embodiment of the present invention and a conventional device;

[0060] Figure 7 Box plots of current signal distribution of cancer samples and normal samples provided in an embodiment of the present invention.

[0061] Figure 8 The electrochemical impedance spectroscopy experiment parameter table provided in the embodiment of the present invention;

[0062] Fig. 9 Schematic diagram of equivalent circuit fitting of impedance spectrum data provided by an embodiment of the present invention

[0063] Fig.10 A graph showing the relationship between the equivalent circuit resistance and the hematocrit provided in an embodiment of the present invention;

[0064] Fig.11 The open circuit potential (OCP) response curve of the hydrogen ion selective electrode provided in the embodiment of the present invention and the linear fitting relationship diagram between pH and OPC;

[0065] Fig.12 A flow chart of the steps of a control method for an electrochemical analysis detection device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0066] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limitations of the present invention. For the step numbers in the following embodiments, they are only provided for the convenience of explanation, and the order between the steps is not limited in any way. The execution order of each step in the embodiment can be adaptively adjusted according to the understanding of those skilled in the art.

[0067] In the description of the present invention, the meaning of "a plurality" is two or more than two. If there is a description of "a first" or "a second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features. In addition, unless otherwise defined, all technical and scientific terms used in this document have the same meaning as those commonly understood by those skilled in the art.

[0068] Figure 1 The schematic diagram of the structure of the electrochemical analysis detection device provided in the embodiment of the present invention is shown in FIG. Figure 1 The embodiment of the present invention provides an electrochemical analysis detection device, characterized in that it includes an input-output module, a core control module, an input signal generation module, a constant potential module, an electrode module, an electrolytic cell and a signal conversion module, the input-output module, the input signal generation module and the signal conversion module are all connected to the core control module, the input signal generation module, the electrode module, the electrolytic cell and the signal conversion module are all connected to the constant potential module, the signal conversion module and the electrode module are all connected to the electrolytic cell, the input-output module is used to obtain the index to be detected, the core control module is used to control the input signal generation module to generate an excitation signal according to the index to be detected, the constant potential module is used to control the potential of the electrode module according to the excitation signal, the electrode module is used to perform an electrochemical reaction with the sample to be detected to generate a first current response signal, the electrolytic cell is used to accommodate the electrode module and the sample to be detected and provide an electrochemical reaction site, the signal conversion module is used to sample and convert the excitation signal and the first current response signal to generate a digital signal, and the core control module is also used to generate a first detection result according to the digital signal and the excitation signal.

[0069] Specifically, refer to Figure 1 , the input and output modules include Figure 1 The PC host computer in the core processing module includes Figure 1 The microprocessor MCU in the input signal generation module includes Figure 1 The digital-to-analog converter DAC, direct digital synthesizer DDS and signal conditioning module in the electrode module Figure 1 Not shown in the figure, it is connected to both the constant potential module and the electrolytic cell, and the information conversion module includes Figure 1 In addition to the current-to-voltage conversion submodule (IV conversion module), the analog-to-digital converter ADC, the synchronous sampling submodule and the synchronous sampling analog-to-digital converter ADC, in this embodiment, it also includes a power supply and a voltage reference module for supplying energy to all components.

[0070] Input and output modules (i.e. Figure 1 The PC host computer in the system communicates with the core control module ( Figure 1The MCU in the electrode module is connected. The user can select the index to be detected through the interactive interface in the PC host computer. According to the index to be detected selected by the user, the MCU will issue corresponding control instructions to the DAC and DDS. The DAC is responsible for converting the digital control signal from the MCU into an analog voltage signal, and the DDS is responsible for generating an AC signal with a specific frequency and amplitude. Subsequently, the DAC and DDS output the signal to the signal conditioning module, which further processes the input signal and adjusts its amplitude, frequency and bias voltage to meet specific detection requirements. The constant potential module will control the potential of the working electrode and the reference electrode in the electrode module according to the output of the signal conditioning module. The working electrode is in the electrolytic cell and directly contacts the sample to be tested, and the target chemical reaction occurs. The electrical signal generated by it is converted into a voltage signal by the IV conversion module, and the reference electrode is used to provide a stable reference potential. The constant potential module monitors the potential between the working electrode and the reference electrode in real time through a feedback loop, and adjusts the input signal in real time to ensure that the potential of the electrode module can be maintained within the set range. The voltage signal converted by the IV conversion module will be converted into a digital signal through the ADC and output to the MCU for processing. The MCU selects a specific method to analyze and calculate it according to the collected data and the corresponding detection index to obtain the detection result. When detecting specific indicators, in addition to converting the current response signal, it is also necessary to sample the excitation signal in the constant potential module through the synchronous sampling submodule, collect the amplitude and phase information of the excitation signal, and then output it to the synchronous sampling analog-to-digital converter ADC to convert it into a digital signal, and then output the digital signal to the MCU for processing to obtain the detection result. Finally, the MCU outputs the detection result to the PC host computer for display.

[0071] Specifically, the indicators that can be detected by the embodiment of the present invention include circulating tumor DNA (ctDNA), hematocrit (HCT) and hydrogen ion concentration (pH). When the detection indicator is ctDNA, a gold electrode is selected as the working electrode, a silver chloride electrode is selected as the reference electrode, and a platinum electrode is selected as the counter electrode. At this time, the signal output by the MCU control signal conditioning module is a cyclic square wave voltage signal, and the constant voltage module controls the potential of the working electrode and the reference electrode to change periodically in the form of a cyclic square wave, specifically: the potential is positively and negatively offset above and below a certain reference potential with a small amplitude square wave signal, and the electrode interface reaction is continuously stimulated. The gold electrode undergoes an oxidation-reduction reaction with the ctDNA in the sample to be tested, generating a corresponding response current, and the response current signal is converted into a voltage signal through the IV conversion module. The ADC collects the voltage signal and transmits it to the MCU. The MCU combines the characteristic peak value of the voltammetric curve with the relationship model of the ctDNA concentration to calculate the detection result of the ctDNA concentration. When the detection index is HCT, the gold electrode is selected as the working electrode, the silver chloride electrode is selected as the reference electrode, and the platinum electrode is selected as the counter electrode. At this time, the signal output by the MCU control signal conditioning module is an AC excitation signal. The constant voltage module keeps the potential between the working electrode and the reference electrode constant on the basis of a specific DC bias potential, and superimposes a small AC excitation signal. Under this condition, the impedance characteristics of the red blood cells in the sample to the electrolyte solution affect the phase and amplitude of the response current. The excitation signal and the response voltage signal are synchronously collected by the synchronous sampling submodule, and the sampling data is digitized by the synchronous sampling analog-to-digital converter ADC and transmitted to the MCU. The MCU calculates the amplitude and phase angle of the response signal through fast Fourier transform, and calculates the HCT detection result according to the corresponding relationship model between the impedance modulus and the hematocrit. When the detection index is pH, a self-made low-cost hydrogen ion selective electrode is selected as the working electrode, and a silver chloride electrode is selected as the reference electrode. At this time, the signal output by the MCU control signal conditioning module is a zero potential signal, and the constant voltage module does not affect the potential of the working electrode and the reference electrode. The two are in a natural open circuit state. The response current signal in this state is converted into a voltage signal through the IV conversion module. The ADC collects the voltage signal and transmits it to the MCU. The MCU calculates the detection result of the hydrogen ion concentration in combination with the fitted correspondence model between the hydrogen ion concentration and the open circuit potential.

[0072] It can be appreciated that, compared with the large size, high cost and cumbersome operation process of the traditional experimental-grade constant potential instrument, the embodiment of the present invention integrates the control logic of the three electrochemical detection methods of cyclic voltammetry, electrochemical impedance spectroscopy and open circuit potential method on the same set of hardware. The detection tasks of different indicators can be completed by simply replacing electrodes and setting detection indicators. The operation is simple, portable and economical, and the use threshold and manufacturing cost of the electrochemical analyzer are reduced. Figure 2 The figure is a comparison of the cyclic voltammetry test curves of the embodiment of the present invention and the traditional device, wherein the horizontal axis E represents the electrode potential, the vertical axis I represents the current, the black curve (Gamry) represents the measurement result of the traditional device, and the red curve (Mestat) represents the measurement result of the embodiment of the present invention. The shapes, peak currents and peak potentials of the two curves are very close, indicating that the performances of the two devices are close. The detection content of the embodiment of the present invention covers early cancer screening (ctDNA), blood health (HCT) and acid-base balance (pH), and can be widely used in a variety of environments, especially in resource-limited areas, and can perform rapid and effective early disease screening, improve public health monitoring capabilities, and provide possibilities for early intervention and treatment, thereby helping to improve patient prognosis and reduce medical costs.

[0073] As a further optional implementation, the indicator to be detected is one of circulating tumor gene concentration, hematocrit and hydrogen ion concentration.

[0074] Specifically, in the present embodiment, the optional indicators to be detected include circulating tumor genes (circulating tumor DNA, ctDNA), hematocrit (hematocrit, HCT) and hydrogen ion concentration (pH). Wherein, ctDNA is a DNA fragment released into the blood by tumor cells, carrying tumor-specific mutations or methylation information, which can be used as a liquid biopsy marker for cancer, and the indicator can be detected by collecting blood samples. By detecting the concentration of ctDNA, rapid initial screening, efficacy monitoring and recurrence prediction of early cancer can be completed. HCT refers to the proportion of red blood cells in whole blood, reflecting the consistency of blood and the oxygen carrying capacity of red blood cells. The height of its value is closely related to the health status of the blood system. Low HCT values ​​indicate diseases such as iron deficiency anemia and chronic disease anemia, and high HCT values ​​indicate dehydration, plateau adaptation or polycythemia vera. By detecting the value of HCT, anemia screening of the test object can be completed, and the health status of the blood system can be quickly diagnosed. The pH value indicates the acidity or alkalinity of a solution and reflects the concentration of hydrogen ions in body fluids. The normal pH value of human blood is 7.35-7.45. Maintaining this range is essential for maintaining life activities. By testing the pH value, it is possible to quickly determine whether the subject has acidosis (such as diabetic ketoacidosis and lactic acidosis), alkalosis, or metabolic-related diseases.

[0075] It can be appreciated that the embodiment of the present invention selects ctDNA, HCT and pH as detection indicators, which can meet the multi-faceted needs of early cancer screening, blood health monitoring and body fluid acid-base balance assessment, has high medical value, is easy to operate and low-cost, and is suitable for scenarios such as primary medical care and personal health monitoring.

[0076] As a further optional implementation, the excitation signal is one of a cyclic square wave voltage signal, an AC excitation signal and a zero potential signal.

[0077] Specifically, in this embodiment, the excitation signal includes a cyclic square wave voltage signal, an AC excitation signal and a zero potential signal, wherein the cyclic square wave voltage signal is used to detect ctDNA by cyclic voltammetry, controlling the electrode potential to fluctuate periodically, stimulating ctDNA to undergo redox reactions, generating characteristic currents, and thereby indicating its concentration; the AC excitation signal is used to detect HCT by electrochemical impedance spectroscopy, and a small-amplitude AC signal is superimposed on the DC bias potential, which can be used to analyze the impedance characteristics of the sample, and the value of HCT can be indicated by the amplitude and phase changes of the signal; the zero potential signal is used to detect pH by the open circuit potential method, without applying an external potential, keeping the electrode in a natural open circuit state, and can indicate the concentration of hydrogen ions.

[0078] As a further optional embodiment, the electrode module includes a gold electrode, a silver chloride electrode, a platinum sheet electrode and a hydrogen ion selective electrode.

[0079] Specifically, in this embodiment, the electrode module includes a gold electrode, a silver chloride electrode, a platinum electrode and a hydrogen ion selective electrode, wherein the gold electrode serves as a working electrode, directly contacts the sample to be tested, and promotes the redox reaction of the target object; the silver chloride electrode serves as a reference electrode, and provides a stable reference potential for accurately controlling the potential of the working electrode; the platinum electrode serves as a counter electrode, and is used to complete the current loop and balance the charge flow in the electrolytic cell; the hydrogen ion selective electrode serves as a working electrode, and is specifically used to detect the hydrogen ion concentration, and has high selectivity for hydrogen ions.

[0080] As a further optional implementation, the signal conversion module includes a synchronous sampling submodule, a current-voltage conversion submodule, an analog-to-digital converter and a synchronous sampling analog-to-digital converter, and the digital signal includes a digital response signal and a synchronously sampled digital response signal.

[0081] As a further optional embodiment, the hydrogen ion selective electrode is prepared by the following steps:

[0082] Select a commercial metal electrode as a base electrode and pretreat the commercial metal electrode;

[0083] The polyaniline conductive intermediate film solution is prepared by using aniline monomer, ammonium persulfate, polyvinyl alcohol and sulfuric acid solution;

[0084] An ion-sensitive membrane solution is prepared by using cyclohexanone, dioctyl sebacate, potassium tetrakis(4-chlorophenyl)borate, carboxypolyvinyl chloride and hydrogen ion carrier;

[0085] The polyaniline conductive intermediate film solution is coated on the surface of the commercial metal electrode to form a conductive intermediate layer;

[0086] The ion-sensitive membrane solution is coated on the surface of the conductive intermediate layer to form a sensitive membrane layer to obtain a hydrogen ion selective electrode.

[0087] Specifically, in this embodiment, the hydrogen ion selective electrode is obtained by modifying a low-cost disposable commercial three-electrode. The selected commercial three-electrode is as follows: Figure 3 As shown, it includes an auxiliary electrode CE, a working electrode WE and a reference electrode RE.

[0088] The surfaces of metal electrodes are usually highly conductive and chemically inert, which allows them to react with a variety of ions. However, this non-selective surface property means that the gold working electrode has similar affinity for different ions in electrochemical reactions, making it difficult to distinguish different types of ions. Therefore, the electrode must be modified. The structure of the modified hydrogen ion selective electrode is shown below: Figure 4 As shown, the outermost layer is a hydrogen ion sensitive membrane, Hydrogen Sensitive Membrane (white layer), the middle layer is a conductive polyaniline (PANI) layer, and the base layer is a base gold electrode (Gold Electrode, GE).

[0089] The sensitive membrane is the core of the ion selective electrode. The membrane can convert the activity of specific ions into potential signals. The preparation process of the hydrogen ion selective outer membrane is introduced below:

[0090] Table 1 is the formula of the outer membrane of the hydrogen ion selective electrode. According to the formula in Table 1, various reagents are accurately weighed and added to a clean and dried transparent screw-mouth glass bottle. The order of adding reagents is very important and should be strictly followed in the order of the numbers specified in the formula.

[0091] Table 1

[0092] Serial number Drug Name effect Theoretical weight (g) Actual weight (g) 1 Cyclohexanone Solvents 2.5 2.5048 2 Dioctyl Sebacate Plasticizers 0.65 0.6554 3 Potassium tetrakis(4-chlorophenyl)borate Organic salt localizer 0.005 0.0045 4 Carboxylic polyvinyl chloride (1.8%) Membrane body 0.34 0.3435 5 Hydrogen ion carrier I Hydrogen ion carrier 0.05 0.0433

[0093] After all reagents have been added, place a cleaned and dried magnetic stirrer in the screw-cap bottle. Place the glass bottle on a constant temperature magnetic stirrer and premix at room temperature (20-25°C) for 10-15 minutes. After premixing, adjust the temperature to 90-100°C and continue stirring at this temperature for 1 hour. During this process, it is necessary to closely observe the state of the reaction system, paying special attention to whether there is granular material on the wall of the glass bottle. Ideally, a transparent and clear organic membrane solution with no obvious granularity should be obtained at the end of the reaction. If abnormal phenomena are observed, such as turbidity or precipitation of the solution, it may be necessary to adjust the reaction conditions or re-formulate.

[0094] After the reaction is completed, the solution is cooled to room temperature. Subsequently, it is placed in an ultrasonic cleaner for 8-10 minutes of ultrasonic treatment. The purpose of this step is to remove the tiny bubbles remaining in the solution and further improve the uniformity and stability of the solution. After the above treatment, a clear, slightly viscous oily solution should be obtained. This solution is the outer membrane precursor of the hydrogen ion selective electrode and can be directly used in the subsequent electrode preparation process.

[0095] The storage and use of organic outer membrane solutions need to follow strict regulations to ensure their effectiveness and safety. The prepared solution should be stored in a refrigerator or professional freezer at 2-8°C, under which conditions it can usually be stored for 3 months. Before use, the solution needs to be taken out of the refrigerated environment and stirred thoroughly at room temperature for 20-30 minutes to allow its temperature to rise evenly and be fully mixed. Subsequently, it is recommended to perform ultrasonic treatment for 8-10 minutes, which can effectively remove tiny bubbles in the solution and improve its uniformity. Before use, the operator should carefully observe the appearance of the solution to ensure that there are no abnormalities such as flocs or precipitates. If any abnormality is found, the batch of solution should be stopped immediately and a new solution should be reconfigured to ensure experimental or production quality.

[0096] The application of conductive polymer intermediate film layers (such as polyaniline, PANI) in electrodes is mainly to improve conductivity.

[0097] As an important conductive polymer, PANI has excellent electronic conductivity. Its addition can significantly improve the electronic conductivity of the electrode material, thereby improving the charge transfer efficiency between the electrode and the electrolyte interface. The preparation of the polyaniline membrane solution is a multi-step precision process, which requires the sequential preparation of three intermediate solutions. First, an 8% PVA aqueous solution is prepared, heated and stirred at 80°C until the PVA is completely dissolved, and then cooled to room temperature to obtain solution A. Next, 0.8g of aniline monomer is added to a mixture consisting of 10mL1M sulfuric acid and 1mL50% phytic acid, stirred at room temperature for 30 minutes, and mixed with solution A to form solution B. At the same time, solution C is prepared, that is, 0.8g of ammonium persulfate (APS) is dissolved in 10mL1M sulfuric acid. Finally, solution B is poured into solution C and stirred for more than 6 hours until a stable dark green polyaniline membrane solution is obtained. The entire process requires strict control of temperature, time and stirring conditions to ensure the quality and stability of the final product.

[0098] After the preparation of the conductive intermediate layer and the ion-sensitive membrane is completed, a polyaniline (PANI) conductive polymer is deposited on the surface of the pretreated gold electrode by drop casting as the intermediate layer of the electrode. This step requires precise control of the concentration and amount of the PANI solution to ensure the formation of a uniform conductive layer with appropriate thickness. After the drop casting is completed, the electrode is placed in a clean, dust-free environment to dry naturally, which usually takes several hours to a day, depending on the ambient temperature and humidity. After the PANI layer is completely dry, a second drop casting is performed, and the pre-prepared ion-sensitive membrane solution is carefully dripped on top of the PANI layer. This process also requires precise control of the amount and distribution of the drop to ensure the formation of a uniform sensitive membrane layer. Afterwards, the electrode is placed in a controlled environment again to dry naturally to prevent external factors such as dust and moisture from affecting the quality of the membrane.

[0099] In order to compare the electron transfer performance of bare gold electrode and PANI modified electrode, the present invention uses electrochemical impedance spectroscopy to study the electrodes. In the Nyquist plot, the semicircle diameter in the high frequency region is related to the charge transfer resistance (R ct ), which is a key indicator for evaluating the electron transport capacity of electrodes. By using ZSimpWin software to perform equivalent circuit fitting on the Nyquist (electrochemical impedance spectroscopy) curve, the R of each electrode can be determined. ct The electrochemical impedance spectrum comparison chart is as follows Figure 5 As shown, Figure 5 The upper left corner is the equivalent circuit model, where R s is the solution resistance, CPE (Constant Phase Element) is the constant phase element, and W1 is the diffusion impedance. Figure 5It is used to simulate the electrochemical behavior of the electrode / electrolyte interface. The black curve (GE) represents the impedance data of the unmodified gold electrode. The blue curve (GE / PANI) represents the impedance data of the gold electrode modified with polyaniline (PANI). The experimental results show that as the electrode surface is modified from bare gold to PANI, the diameter of the semicircle in the Nyquist plot decreases, which intuitively reflects the improvement of the electrode's charge transfer ability. Specifically, the R ct The value is 677.3Ω, while the R ct The large difference clearly shows that PANI modification significantly enhances the charge transfer efficiency and reduces the charge transfer resistance of the electrode. ct The high value means that it has the best electron transport capability, which may be attributed to the electrical conductivity and large specific surface area of ​​PANI, which provide favorable conditions for the rapid transfer of electrons at the electrode / electrolyte interface.

[0100] As a further optional implementation, the indicator to be detected is the concentration of circulating tumor genes, and the second detection result is obtained by the following steps:

[0101] The core control module controls the input signal generation module to generate a cyclic square wave voltage signal;

[0102] A gold electrode was used as the working electrode, a silver chloride electrode was used as the reference electrode and a platinum electrode was used as the counter electrode;

[0103] The potential of the gold electrode and the silver chloride electrode is controlled by a constant potential module according to a cyclic square wave voltage signal;

[0104] generating a second current response signal through the gold electrode;

[0105] Converting the second current response signal into a first voltage response signal through a current-voltage conversion submodule;

[0106] Converting the first voltage response signal into a first digital response signal through an analog-to-digital converter;

[0107] The core control module draws a voltammetric curve according to the first digital response signal and the cyclic square wave voltage signal, and calculates the relationship between the peak current in the voltammetric curve and the circulating tumor gene concentration through a preset first fitting model to obtain a second detection result.

[0108] Specifically, in the embodiment of the present invention, the electrode configuration is a gold working electrode with a diameter of 2 mm, an Ag / AgCl reference electrode, and a platinum counter electrode. The electrolyte is a 1 mmol / L ferrocene solution and a 0.1 mol / L potassium chloride solution. The cyclic square wave voltammetry test parameters are set as follows: initial potential 0 V, end potential 0.5 V, potential increment 10 mV, frequency 50 Hz, and pulse potential 25 mV.

[0109] The concentration of ctDNA was determined by the following steps:

[0110] (1) Prepare 1 mmol / L ferrocene solution and 0.1 mol / L potassium chloride solution;

[0111] (2) Pretreatment of plasma DNA samples: Take 50 μL of plasma DNA sample and dissolve it in 0.5 mL of SSC buffer at 25°C, 5% and pH=7.

[0112] (3) Electrode pretreatment: First, the gold working electrode with a diameter of 0.3 μm was polished with alumina polishing powder, then rinsed with deionized water, ultrasonicated in acetone and deionized water for 5 min, and finally dried under nitrogen flow. The dried gold working electrode was incubated in the pretreated plasma DNA sample for 10 min.

[0113] (4) 1mmol / L ferrocene solution and 0.1mol / L potassium chloride solution were selected as electrolytes, and the blank group was free of plasma DNA samples. Under the above measurement conditions, the blank group and plasma DNA samples were electrochemically measured in turn using cyclic square wave voltammetry. At this time, the signal output by the MCU control signal conditioning module is a cyclic square wave voltage signal, and the constant voltage module controls the potential of the working electrode and the reference electrode to change periodically in the form of a cyclic square wave. Specifically, the potential is positively and negatively offset above and below a certain reference potential in a small-amplitude square wave signal to continuously stimulate the electrode interface reaction. The gold electrode undergoes an oxidation-reduction reaction with the ctDNA in the sample to be tested to generate a corresponding response current. The response current signal is converted into a voltage signal through the IV conversion module. The ADC collects the voltage signal and transmits it to the MCU. The MCU combines the characteristic peak value of the voltammetry curve with the relationship model of the ctDNA concentration to calculate the detection result of the ctDNA concentration. The obtained cyclic square wave voltammetry comparison curve is shown as follows. Figure 6 As shown, the black curve represents the measurement result of the traditional device, and the red curve represents the measurement result of the embodiment of the present invention. The shapes, peak currents and peak potentials of the two curves are very close, indicating that the performances of the two devices are similar.

[0114] (5) Read the characteristic peak current of the plasma DNA sample in the range of 0.25V to 0.35V, and obtain the result after processing. The result is as follows Figure 7 As shown, Figure 7Box plot of current signal distribution of cancer samples and normal samples.

[0115] As a further optional implementation, the indicator to be detected is hematocrit, and the third test result is obtained by the following steps:

[0116] The core control module controls the input signal generation module to generate an AC excitation signal;

[0117] A gold electrode was used as the working electrode, a silver chloride electrode was used as the reference electrode and a platinum electrode was used as the counter electrode;

[0118] The potential of the gold electrode and the silver chloride electrode is controlled according to the AC excitation signal by a constant potential module;

[0119] generating a third current response signal through the gold electrode;

[0120] converting the third current response signal into a second voltage response signal through a current-voltage conversion submodule;

[0121] The amplitude and phase of the AC excitation signal and the second voltage response signal are collected by a synchronous sampling submodule;

[0122] The amplitude and phase of the AC excitation signal and the second voltage response signal are converted into a synchronously sampled digital response signal through a synchronously sampled analog-to-digital conversion submodule;

[0123] The core control module draws an impedance spectrum curve according to the synchronously sampled digital response signal, and calculates the relationship between the impedance spectrum curve and the hematocrit according to a preset second fitting model to obtain a third detection result.

[0124] Specifically, in the embodiment of the present invention, the electrode is configured to have an area of ​​3.14 mm 2 Gold working electrode, Ag / AgCl reference electrode, platinum counter electrode, electrochemical impedance spectroscopy experimental parameters such as Figure 8 As shown, DC Voltage (V) is a constant DC potential, which is set to 0V relative to the open circuit potential (EOC). AC Voltage (mV pp) is the amplitude of the applied small AC signal, expressed in peak-to-peak (pp), and its value is 10mV. InitialFrequency (Hz) is the experimental starting frequency, expressed in Hertz (Hz), and its value is 10 5 Hz. FinalFrequency(Hz) is the starting frequency of the experiment, and its value is 1Hz. Points / decade is the number of points collected for each order of magnitude of frequency, and its value is 10. Initial Delay is the delay time before the experiment starts, in seconds, and its value is 5.

[0125] The concentration of HCT was determined by the following steps:

[0126] (1) Prepare sheep red blood cells with different hematocrit;

[0127] (2) According to the above parameters and electrodes, the impedance spectrum test is performed. At this time, the signal output by the MCU control signal conditioning module is an AC excitation signal. The constant voltage module keeps the potential between the working electrode and the reference electrode constant on the basis of a specific DC bias potential, and superimposes a small AC excitation signal. Under this condition, the impedance characteristics of the red blood cells in the sample to the electrolyte solution affect the phase and amplitude of the response current. The excitation signal and the response voltage signal are synchronously collected by the synchronous sampling submodule, and the synchronous sampling analog-to-digital converter ADC is used to convert the excitation signal into a signal.

[0128] The sampled data is de-DC-biased and amplified, and then subjected to a fast discrete Fourier transform to obtain the amplitude U1 and phase θ1 of the excitation voltage signal, and the amplitude U2 and phase θ2 of the response voltage signal.

[0129] The impedance modulus Z of the electrolytic cell mod The calculation formula is:

[0130] Z mod =U1 / U2×A2 / A1×RTIA

[0131] The calculation formula of the impedance phase angle θ of the electrolytic cell is:

[0132] θ=θ2-θ1

[0133] Among them, RTIA is the resistance value of the transimpedance amplifier, A1 is the amplification factor of the excitation voltage signal, and A2 is the amplification factor of the response voltage signal.

[0134] The impedance and phase angle at the current frequency are calculated based on the obtained amplitude and phase angle, and the impedance measurement at the next frequency is performed until the impedance spectrum measurement within the experimental setting frequency range is completed.

[0135] (3) Perform equivalent circuit fitting on the obtained impedance spectrum data. The equivalent circuit is as follows: Fig. 9 As shown, it is composed of an impedance element Q and an equivalent resistor R in series;

[0136] (4) Construct Fig.10 The relationship diagram between R and hematocrit in the above equivalent circuit is shown, the horizontal axis is the proportion of red blood cells in the total blood volume, the vertical axis is the resistance value fitted by the equivalent circuit, and the red line in the figure represents the linear fitting result of R and hematocrit.

[0137] As an optional implementation, the indicator to be detected is hydrogen ion concentration, and the fourth detection result is obtained by the following steps:

[0138] The core control module controls the input signal generation module to generate a zero potential signal;

[0139] A hydrogen ion selective electrode was used as the working electrode and a silver chloride electrode was used as the reference electrode;

[0140] The potentials of the hydrogen ion selective electrode and the silver chloride electrode are controlled according to the zero potential signal by a constant potential module;

[0141] using an open circuit potential between the hydrogen ion selective electrode and the silver chloride electrode as a fourth current response signal;

[0142] Converting the converted fourth current response signal into a third voltage response signal through a current-voltage conversion submodule;

[0143] converting the third voltage response signal into a second digital response signal through an analog-to-digital converter;

[0144] The core control module calculates the relationship between the second digital response signal and the hydrogen ion concentration according to a preset third fitting model to obtain a fourth detection result.

[0145] Specifically, in this embodiment, after the electrode is manufactured and characterized to prove its reliability, the sensitivity of the electrode in detecting hydrogen ion concentration is investigated. The electrodes are immersed in PBS (phosphate buffer) buffer solutions of different pH values ​​(pH = 4.00 ~ 9.00) for 10 seconds, respectively, in order to fully contact the electrode surface with the test solution, and then start recording the open circuit potential. The response current signal in this state is converted into a voltage signal through the IV conversion module, and the ADC collects the voltage signal and transmits it to the MCU. The open circuit potential (OCP) response curve of the hydrogen ion selective electrode and the linear fitting relationship between pH and OPC are obtained as shown in the figure. Fig.11 As shown. Combined Fig.11 It can be seen that as the pH increases, the open circuit potential increases linearly, and the corresponding fitting equation is:

[0146] ocp(V)=52.57PH+465.79,R2=0.99

[0147] Where ocp(V) is the open circuit potential in volts, PH is the pH value of the solution, and R2 is the correlation coefficient, which is close to 1, indicating that the linear relationship between ocp and PH is good.

[0148] Subsequently, the MCU calculates the detection result of the hydrogen ion concentration by combining the fitted correspondence model between the hydrogen ion concentration and the open circuit potential.

[0149] Reference Fig.12The embodiment of the present invention provides a control method for an electrochemical analysis detection device, which is implemented by the above-mentioned electrochemical analysis detection device, and includes the following steps:

[0150] S101, obtaining the index to be detected through the input and output module;

[0151] S102, controlling the input signal generation module to generate an excitation signal according to the indicator to be detected by the core control module;

[0152] S103, controlling the potential of the electrode module according to the excitation signal through the constant potential module;

[0153] S104, generating a first current response signal by performing an electrochemical reaction between the electrode module and the sample to be tested;

[0154] S105, accommodating the electrode module and the sample to be tested by the electrolytic cell to provide an electrochemical reaction site;

[0155] S106, sampling and converting the excitation signal and the first current response signal through a signal conversion module to generate a digital signal;

[0156] S107 . Generate a first detection result according to the digital signal and the excitation signal through a core control module.

[0157] It can be understood that the contents of the above system embodiments are all applicable to the present method embodiments, the functions specifically implemented by the present method embodiments are the same as those of the above system embodiments, and the beneficial effects achieved are also the same as those achieved by the above system embodiments.

[0158] It should be appreciated that embodiments of the present invention may be implemented or enforced by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable memory. The above methods may be implemented in a computer program using standard programming techniques, including a non-transitory computer-readable storage medium configured with a computer program, wherein the storage medium so configured causes the computer to operate in a specific and predefined manner, according to the methods and drawings described in the specific embodiments. Each program may be implemented in a high-level procedural or object-oriented programming language to communicate with a computer system. However, if desired, the program may be implemented in an assembly or machine language. In any case, the language may be a compiled or interpreted language. In addition, the program may be run on a programmed dedicated integrated circuit for this purpose.

[0159] Furthermore, the operations of the processes described herein may be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The processes described herein (or variations and / or combinations thereof) may be performed under the control of one or more computer systems configured with executable instructions, and may be implemented as code (e.g., executable instructions, one or more computer programs, or one or more applications) that is executed collectively on one or more processors, by hardware, or a combination thereof. The computer programs described above include a plurality of instructions that may be executed by one or more processors.

[0160] Further, the above method can be implemented in any type of computing platform that is operably connected to a suitable computer, including but not limited to a personal computer, a minicomputer, a mainframe, a workstation, a network or distributed computing environment, a separate or integrated computer platform, or in communication with a charged particle tool or other imaging device, etc. Various aspects of the present invention can be implemented in machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, an optical read and / or write storage medium, a RAM, a ROM, etc., so that it can be read by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the process described herein. In addition, the machine-readable code, or a portion thereof, can be transmitted via a wired or wireless network. When such media includes instructions or programs that implement the steps described above in conjunction with a microprocessor or other data processor, the invention described herein includes these and other different types of non-transitory computer-readable storage media. When programmed according to the methods and techniques described in the present invention, the present invention also includes the computer itself.

[0161] The computer program can be applied to input data to perform the functions described herein, thereby converting the input data to generate output data stored in a non-volatile memory. The output information can also be applied to one or more output devices such as a display. In a preferred embodiment of the present invention, the converted data represents physical and tangible objects, including specific visual depictions of physical and tangible objects produced on the display.

[0162] The above are only preferred embodiments of the present invention. The present invention is not limited to the above embodiments. As long as the technical effects of the present invention are achieved by the same means, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention. Within the scope of protection of the present invention, its technical solutions and / or implementation methods may have various modifications and changes.

Claims

1. An electrochemical analysis detection device, characterized in that: The invention comprises an input-output module, a core control module, an input signal generating module, a constant potential module, an electrode module, an electrolytic cell and a signal conversion module, wherein the input-output module, the input signal generating module and the signal conversion module are all connected to the core control module, the input signal generating module, the electrode module, the electrolytic cell and the signal conversion module are all connected to the constant potential module, the signal conversion module and the electrode module are all connected to the electrolytic cell, the input-output module is used to obtain an indicator to be detected, the core control module is used to control the input signal generating module to generate an excitation signal according to the indicator to be detected, the constant potential module is used to control the potential of the electrode module according to the excitation signal, the electrode module is used to perform an electrochemical reaction with a sample to be detected to generate a first current response signal, the electrolytic cell is used to accommodate the electrode module and the sample to be detected and provide an electrochemical reaction site, the signal conversion module is used to sample and convert the excitation signal and the first current response signal to generate a digital signal, and the core control module is also used to generate a first detection result according to the digital signal and the excitation signal.

2. An electrochemical analysis detection device according to claim 1, characterized in that: The index to be detected is one of circulating tumor gene concentration, hematocrit and hydrogen ion concentration.

3. An electrochemical analysis detection device according to claim 2, characterized in that: The excitation signal is one of a cyclic square wave voltage signal, an AC excitation signal and a zero potential signal.

4. An electrochemical analysis detection device according to claim 3, characterized in that: The electrode module includes a gold electrode, a silver chloride electrode, a platinum sheet electrode and a hydrogen ion selective electrode.

5. An electrochemical analysis detection device according to claim 4, characterized in that: The signal conversion module includes a synchronous sampling submodule, a current-voltage conversion submodule, an analog-to-digital converter and a synchronous sampling analog-to-digital converter, and the digital signal includes a digital response signal and a synchronous sampling digital response signal.

6. An electrochemical analysis detection device according to claim 5, characterized in that: The hydrogen ion selective electrode is prepared by the following steps: Selecting a commercial metal electrode as a base electrode and pretreating the commercial metal electrode; The polyaniline conductive intermediate film solution is prepared by using aniline monomer, ammonium persulfate, polyvinyl alcohol and sulfuric acid solution; An ion-sensitive membrane solution is prepared by using cyclohexanone, dioctyl sebacate, potassium tetrakis(4-chlorophenyl)borate, carboxypolyvinyl chloride and hydrogen ion carrier; Applying the polyaniline conductive intermediate film solution on the surface of the commercial metal electrode to form a conductive intermediate layer; The ion-sensitive membrane solution is coated on the surface of the conductive intermediate layer to form a sensitive membrane layer, thereby obtaining the hydrogen ion selective electrode.

7. An electrochemical analysis detection device according to claim 5, characterized in that: The index to be detected is the circulating tumor gene concentration, and the second detection result is obtained by the following steps: Controlling the input signal generation module to generate the cyclic square wave voltage signal through the core control module; Using the gold electrode as a working electrode, the silver chloride electrode as a reference electrode and the platinum sheet electrode as a counter electrode; Controlling the potentials of the gold electrode and the silver chloride electrode according to the cyclic square wave voltage signal by the constant potential module; generating the second current response signal through the gold electrode; converting the second current response signal into a first voltage response signal by the current-voltage conversion submodule; converting the first voltage response signal into a first digital response signal by the analog-to-digital converter; The core control module draws a voltammetric curve according to the first digital response signal and the cyclic square wave voltage signal, and calculates the relationship between the peak current in the voltammetric curve and the circulating tumor gene concentration through a preset first fitting model to obtain the second detection result.

8. An electrochemical analysis detection device according to claim 5, characterized in that: The indicator to be detected is the hematocrit, and the third test result is obtained by the following steps: Controlling the input signal generation module to generate the AC excitation signal through the core control module; Using the gold electrode as a working electrode, the silver chloride electrode as a reference electrode and the platinum sheet electrode as a counter electrode; Controlling the potentials of the gold electrode and the silver chloride electrode according to the AC excitation signal by the constant potential module; generating the third current response signal through the gold electrode; converting the third current response signal into the second voltage response signal through the current-voltage conversion submodule; Acquiring the amplitude and phase of the AC excitation signal and the second voltage response signal through the synchronous sampling submodule; Converting the amplitude and phase of the AC excitation signal and the second voltage response signal into the synchronous sampling digital response signal through the synchronous sampling analog-to-digital conversion submodule; The core control module draws an impedance spectrum curve according to the synchronously sampled digital response signal, and calculates the relationship between the impedance spectrum curve and the hematocrit according to a preset second fitting model to obtain the third detection result.

9. An electrochemical analysis detection device according to claim 6, characterized in that: The indicator to be detected is the hydrogen ion concentration, and the fourth detection result is obtained by the following steps: Controlling the input signal generating module to generate the zero potential signal through the core control module; using the hydrogen ion selective electrode as a working electrode and the silver chloride electrode as a reference electrode; Controlling the potentials of the hydrogen ion selective electrode and the silver chloride electrode according to the zero potential signal by the constant potential module; using the open circuit potential between the hydrogen ion selective electrode and the silver chloride electrode as the fourth current response signal; Converting the fourth current response signal into a third voltage response signal through the current-voltage conversion submodule; converting the third voltage response signal into a second digital response signal by the analog-to-digital converter; The core control module calculates the relationship between the second digital response signal and the hydrogen ion concentration according to a preset third fitting model to obtain the fourth detection result.

10. A control method for an electrochemical analysis detection device, which is implemented by the electrochemical analysis detection device according to any one of claims 1 to 9, characterized in that: The following steps are involved: Obtaining the indicator to be detected through the input and output module; Controlling the input signal generation module to generate an excitation signal according to the indicator to be detected by the core control module; Controlling the potential of the electrode module according to the excitation signal by the constant potential module; The electrode module performs an electrochemical reaction with the sample to be tested to generate a first current response signal; The electrolytic cell accommodates the electrode module and the sample to be tested, providing a place for electrochemical reaction; The signal conversion module samples and converts the excitation signal and the first current response signal to generate a digital signal; A first detection result is generated by the core control module according to the digital signal and the excitation signal.

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