Electrochemical analysis detection device and control method

Abstract

The application provides an electrochemical analysis detection device and a control method, and the device comprises the following modules: an input-output module, a core control module, a constant potential module, an electrode module, an electrolytic cell, a signal conversion module and a display module. The input-output module is used for obtaining a detection index; the core control module is used for controlling an input signal generation module to generate an excitation signal according to the detection index; the constant potential module is used for controlling the potential of the electrode module according to the excitation signal; the electrode module is used for performing electrochemical reaction with a sample to be detected to generate a first current response signal; the electrolytic cell is used for accommodating the electrode module and the sample to be detected to provide an electrochemical reaction place; the signal conversion module is used for sampling and converting the excitation signal and the first current response signal to generate a digital signal; and the core control module is used for generating a first detection result according to the digital signal and the excitation signal. The control logic of various electrochemical detection methods is integrated on the same set of hardware, different indexes can be detected through simple operation, the use threshold and manufacturing cost of the electrochemical analyzer are reduced, and the application can be widely used in the technical field of electrochemical analysis.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical detection technology, and particularly relates to an electrochemical analysis and detection device and control method. Background Technology

[0002] According to data from the World Health Organization (WHO) and the International Agency for Research on Cancer (IARC), approximately 20 million new cancer cases and 9.7 million cancer deaths occurred globally in 2022. Nearly 2 billion people worldwide suffer from anemia, representing about 25% of the world's population. The highest prevalence (67.6%) is among children and women of childbearing age in Africa, and this is considered a global health problem affecting both developed and developing countries. Early disease screening is a crucial component of modern preventive medicine, playing a significant role in improving cure rates and reducing mortality. ctDNA can serve as a blood biopsy biomarker, playing an important role in the early diagnosis, treatment monitoring, and prognostic assessment of malignant tumors.

[0003] Compared with traditional optical, mass spectrometry, and immunological disease detection methods, electrochemical detection methods have several advantages: First, in terms of sensitivity, electrochemical detection methods can achieve detection limits in the pM or even fM range, effectively capturing trace changes in biomarkers in the early stages of disease; second, in terms of specificity, electrochemical detection methods can effectively distinguish target substances in complex samples (such as blood), without requiring cumbersome pretreatment 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 early diagnosis; finally, in terms of wide applicability, electrochemical methods are not only suitable for virus detection, but also for the detection of bacteria, tumor markers, and many other diseases, and their flexibility and adaptability enable them to meet the diagnostic needs of different types of diseases.

[0004] Potentiostats are crucial instruments for 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-constrained regions. Summary of the Invention

[0005] The purpose of this invention is to at least partially solve one of the technical problems existing in the prior art.

[0006] Therefore, one objective of this invention is to provide an electrochemical analysis and detection device that integrates the control logic of multiple electrochemical detection methods onto the same hardware. By simply changing the electrodes and setting the detection indicators, the detection tasks of different indicators can be completed. It is simple to operate, portable and economical, and reduces the threshold for use and manufacturing cost of electrochemical analyzers.

[0007] The first technical solution adopted in this invention is:

[0008] An electrochemical analysis and detection device is characterized by comprising 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 both connected to the electrolytic cell. The input / output module is used to acquire a target indicator. The core control module is used to control the input signal generation module to generate an excitation signal based on the target indicator. The constant potential module is used to control the potential of the electrode module based on the excitation signal. The electrode module is used to perform an electrochemical reaction with the sample to be tested, generating a first current response signal. The electrolytic cell is used to contain the electrode module and the sample to be tested, providing a site for the electrochemical reaction. The signal conversion module is used to sample and convert the excitation signal and the first current response signal to generate a digital signal. The core control module is also used to generate a first detection result based on the digital signal and the excitation signal.

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

[0010] Furthermore, the excitation signal is one of the following: 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-to-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] Furthermore, the hydrogen ion selective electrode is prepared by the following steps:

[0014] Commercial metal electrodes were selected as the base electrodes, and the commercial metal electrodes were pretreated.

[0015] A polyaniline conductive interlayer solution was prepared by using aniline monomer, ammonium persulfate, polyvinyl alcohol, and sulfuric acid solution.

[0016] An ion-sensitive membrane solution was prepared by using cyclohexanone, dioctyl sebacate, potassium tetra(4-chlorophenyl)borate, carboxylated polyvinyl chloride and a hydrogen ion carrier.

[0017] The polyaniline conductive intermediate film solution is coated onto the surface of the commercial metal electrode to form a conductive intermediate layer;

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

[0019] Furthermore, the indicator to be detected is the concentration of circulating tumor genes, and the second detection result is obtained through the following steps:

[0020] The core control module controls the input signal generation module to generate the cyclic square wave voltage signal.

[0021] The gold electrode is used as the working electrode, the silver chloride electrode is used as the reference electrode, and the platinum sheet electrode is used as the counter electrode.

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

[0023] The second current response signal is generated through the gold electrode;

[0024] The second current response signal is converted into a first voltage response signal through the current-to-voltage conversion submodule;

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

[0026] The core control module plots an volt-ampere curve based on the first digital response signal and the cyclic square wave voltage signal, and calculates the relationship between the peak current in the volt-ampere curve and the concentration of the circulating tumor gene using a preset first fitting model to obtain the second detection result.

[0027] Furthermore, the indicator to be detected is the hematocrit, and the third detection result is obtained through the following steps:

[0028] The core control module controls the input signal generation module to generate the AC excitation signal;

[0029] The gold electrode is used as the working electrode, the silver chloride electrode is used as the reference electrode, and the platinum sheet electrode is used as the counter electrode.

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

[0031] The third current response signal is generated through the gold electrode;

[0032] The third current response signal is converted into the second voltage response signal by the current-to-voltage conversion submodule;

[0033] The amplitude and phase of the AC excitation signal and the second voltage response signal are acquired by the synchronous sampling submodule.

[0034] The synchronous sampling analog-to-digital conversion submodule converts the amplitude and phase of the AC excitation signal and the second voltage response signal into the synchronous sampling digital response signal.

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

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

[0037] The core control module controls the input signal generation module to generate the zero potential signal;

[0038] The hydrogen ion selective electrode is used as the working electrode and the silver chloride electrode is used as the reference electrode.

[0039] The constant potential module controls the potentials of the hydrogen ion selective electrode and the silver chloride electrode based on the zero potential signal;

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

[0041] The current-to-voltage conversion submodule converts the converted fourth current response signal into a third voltage response signal.

[0042] The analog-to-digital converter converts the third voltage response signal into a second digital response signal.

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

[0044] The second technical solution adopted in this invention is:

[0045] A control method for an electrochemical analysis and detection device, used to implement the above-mentioned electrochemical analysis and detection device, includes the following steps:

[0046] The indicator to be detected is obtained through the input / output module;

[0047] The core control module controls the input signal generation module to generate an excitation signal based on the indicator to be detected.

[0048] The constant potential module controls the potential of the electrode module according to the excitation signal;

[0049] The electrode module reacts electrochemically with the sample to be tested to generate a first current response signal.

[0050] The electrolytic cell houses the electrode module and the sample to be tested, providing a site for electrochemical reactions.

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

[0052] The core control module generates a first detection result based on the digital signal and the excitation signal.

[0053] The beneficial effects of this invention are as follows: By integrating the control logic of three electrochemical detection methods—cyclic voltammetry, electrochemical impedance spectroscopy, and open-circuit potential method—onto a single hardware device, this invention allows for the detection of different indicators simply by changing electrodes and setting detection parameters. It is simple to operate, portable, and economical, lowering the barrier to entry and manufacturing cost of electrochemical analyzers. Furthermore, this invention further reduces the manufacturing cost of the device by designing a low-cost method for preparing a hydrogen ion-selective electrode. In addition, the scope of detection covered by this invention includes early cancer screening (ctDNA), blood health (HCT), and acid-base balance (pH), enabling wide application in various environments. Especially in resource-limited areas, it allows for rapid and effective early disease screening, improving public health monitoring capabilities and providing possibilities for early intervention and treatment, thereby helping to improve patient prognosis and reduce medical costs. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of the structure of an electrochemical analysis and detection device provided in an embodiment of the present invention;

[0055] Figure 2 This is a comparison chart of cyclic voltammetry test curves between an electrochemical analysis and detection device and a traditional device provided in an embodiment of the present invention;

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

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

[0058] Figure 5This is a comparison diagram of electrochemical impedance spectroscopy provided in an embodiment of the present invention;

[0059] Figure 6 A curve comparison of the detection results of an electrochemical analysis and detection device and a traditional equipment using cyclic square wave voltammetry, provided for an embodiment of the present invention;

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

[0061] Figure 8 Table of electrochemical impedance spectroscopy experimental parameters provided for embodiments of the present invention;

[0062] Figure 9 A schematic diagram of the equivalent circuit fitting for impedance spectrum data provided in an embodiment of the present invention.

[0063] Figure 10 This is a diagram showing the relationship between the equivalent circuit resistance and hematocrit provided in an embodiment of the present invention.

[0064] Figure 11 The open circuit potential (OCP) response curve and the linear fitting relationship between pH and OPC of the hydrogen ion selective electrode provided in the embodiments of the present invention are shown.

[0065] Figure 12 A flowchart illustrating the steps of a control method for an electrochemical analysis and detection device provided in an embodiment of the present invention. Detailed Implementation

[0066] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. The step numbers in the following embodiments are set only for ease of explanation, and there is no limitation on the order between the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0067] In the description of this invention, "multiple" means two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or the order of the indicated technical features. Furthermore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.

[0068] Figure 1 This is a schematic diagram of the electrochemical analysis and detection device provided in an embodiment of the present invention, with reference to... Figure 1 This invention provides an electrochemical analysis and detection device, characterized by comprising 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, input signal generation module, and signal conversion module are all connected to the core control module; the input signal generation module, electrode module, electrolytic cell, and signal conversion module are all connected to the constant potential module; and the signal conversion module and electrode module are both connected to the electrolytic cell. The input / output module is used to acquire the target index. The core control module is used to control the input signal generation module to generate an excitation signal based on the target index. The constant potential module is used to control the potential of the electrode module based on the excitation signal. The electrode module is used to perform an electrochemical reaction with the sample to be tested, generating a first current response signal. The electrolytic cell is used to contain the electrode module and the sample to be tested, providing a site for the electrochemical reaction. The signal conversion module is used to sample and convert the excitation signal and the first current response signal to generate a digital signal. The core control module is also used to generate a first detection result based on the digital signal and the excitation signal.

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

[0070] Input / output module (i.e.) Figure 1 The PC host computer (in the system) communicates with the core control module (through the serial communication interface UART and the Type-C interface) Figure 1The system connects to an MCU (Microcontroller Unit), allowing users to select the target indicator via an interactive interface on a PC. Based on the selected indicator, the MCU sends corresponding control commands to the DAC and DDS (Digital Signal Processor). The DAC converts the digital control signal from the MCU into an analog voltage signal, while the DDS generates an AC signal with a specific frequency and amplitude. The DAC and DDS then output the signal to the signal conditioning module, which further processes the input signal, adjusting its amplitude, frequency, and bias voltage to meet specific detection requirements. The constant potential module controls the potential of the working electrode and reference electrode in the electrode module based on the output of the signal conditioning module. The working electrode is in direct contact with the sample in the electrolytic cell, undergoing a targeted chemical reaction. The resulting electrical signal is converted into a voltage signal by the IV conversion module. The reference electrode provides 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, adjusting the input signal accordingly to ensure the electrode module's potential remains within the set range. The voltage signal obtained by the IV conversion module is converted into a digital signal by an ADC and output to the MCU for processing. The MCU analyzes and calculates the collected data and corresponding detection indicators using a specific method to obtain the detection result. When detecting specific indicators, in addition to converting the current response signal, the excitation signal in the constant potential module needs to be sampled by a synchronous sampling submodule to collect the amplitude and phase information of the excitation signal. This information is then output to the synchronous sampling analog-to-digital converter (ADC) to be converted into a digital signal, which is then output to the MCU for processing to obtain the detection result. Finally, the MCU outputs the detection result to a PC for display.

[0071] Specifically, the detectable indicators in this embodiment of the invention include circulating tumor DNA (ctDNA), hematocrit (HCT), and hydrogen ion concentration (pH). When ctDNA is detected, a gold electrode is selected as the working electrode, a silver chloride electrode as the reference electrode, and a platinum electrode as the counter electrode. The signal output by the MCU control signal conditioning module is a cyclic square wave voltage signal. The constant voltage module controls the potentials of the working electrode and the reference electrode to change periodically in the form of a cyclic square wave. Specifically, the potential shifts positively and negatively above and below a certain reference potential with a small-amplitude square wave signal, continuously stimulating the electrode interface reaction. The gold electrode undergoes a redox reaction with the ctDNA in the sample, generating a corresponding response current. The IV conversion module converts the response current signal into a voltage signal. The ADC acquires the voltage signal and transmits it to the MCU. The MCU calculates the detection result of the ctDNA concentration using a model that combines the characteristic peak value of the voltammetric curve with the ctDNA concentration. When the detection index is HCT, a gold electrode is selected as the working electrode, a silver chloride electrode as the reference electrode, and a platinum sheet electrode as the counter electrode. The signal output from the MCU control signal conditioning module is an AC excitation signal. The constant voltage module maintains the potential between the working electrode and the reference electrode at a specific DC bias potential, while simultaneously superimposing a small-amplitude AC excitation signal. Under these conditions, the impedance characteristics of red blood cells in the sample to the electrolyte solution affect the phase and amplitude of the response current. The excitation signal and response voltage signal are synchronously acquired by the synchronous sampling submodule. The data is digitized by a synchronous sampling analog-to-digital converter (ADC) and transmitted to the MCU. The MCU calculates the amplitude and phase angle of the response signal using a fast Fourier transform, and calculates the HCT detection result based on the correspondence model between impedance modulus and 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. The constant voltage module does not affect the potential of the working electrode and the reference electrode. Both are in a natural open circuit state. The response current signal in this state is converted into a voltage signal by the IV conversion module. The ADC collects the voltage signal and transmits it to the MCU. The MCU calculates the detection result of hydrogen ion concentration by combining the fitted hydrogen ion concentration and open circuit potential correspondence model.

[0072] It can be recognized that, compared with the large size, high cost and cumbersome operation process of traditional experimental potentiostats, the embodiments of the present invention integrate the control logic of three electrochemical detection methods, namely cyclic voltammetry, electrochemical impedance spectroscopy and open circuit potential method, into the same set of hardware. By simply changing the electrodes and setting the detection index, the detection tasks of different indicators can be completed. It is simple to operate, portable and economical, and reduces the threshold for use and manufacturing cost of electrochemical analyzers. Figure 2 This is a comparison of the cyclic voltammetry test curves of the embodiments of the present invention and conventional equipment. The horizontal axis E represents electrode potential, and the vertical axis I represents current. The black curve (Gamry) represents the measurement results of the conventional equipment, and the red curve (Mestat) represents the measurement results of the embodiments of the present invention. The shapes, peak currents, and peak potentials of the two curves are very similar, indicating that the performance of the two devices is similar. The scope of detection in the embodiments of the present invention covers early cancer screening (ctDNA), blood health (HCT), and acid-base balance (pH), and can be widely applied in various environments. Especially in resource-limited areas, it enables rapid and effective early disease screening, improves public health monitoring capabilities, and provides possibilities for early intervention and treatment, thereby helping to improve patient prognosis and reduce medical costs.

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

[0074] Specifically, in this embodiment, optional indicators to be detected include circulating tumor DNA (ctDNA), hematocrit (HCT), and hydrogen ion concentration (pH). ctDNA is a DNA fragment released into the bloodstream by tumor cells, carrying tumor-specific mutations or methylation information. It can serve as a liquid biopsy biopsy marker for cancer, and this indicator can be detected by collecting blood samples. By detecting the concentration of ctDNA, rapid initial screening for early-stage cancer, monitoring treatment efficacy, and predicting recurrence can be achieved. HCT refers to the proportion of red blood cells in whole blood, reflecting blood viscosity and the oxygen-carrying capacity of red blood cells. Its value is closely related to the health status of the blood system. Low HCT values ​​suggest iron deficiency anemia, chronic anemia, etc., while high HCT values ​​suggest dehydration, altitude acclimatization, or polycythemia vera, etc. By detecting HCT values, anemia screening can be performed on the tested subjects, and the health status of the blood system can be quickly diagnosed. pH value indicates the acidity or alkalinity of a solution, reflecting the concentration of hydrogen ions in body fluids. The normal pH value of human blood is 7.35-7.45, and maintaining this range is crucial for sustaining life. By detecting pH value, it is possible to quickly determine whether a subject has acidosis (such as diabetic ketoacidosis and lactic acidosis), alkalosis, or metabolic-related diseases.

[0075] It can be recognized that the present invention selects ctDNA, HCT and pH as detection indicators, which can meet the needs of early cancer screening, blood health monitoring and body fluid acid-base balance assessment, and has high medical value. Moreover, it is convenient to operate, low in cost, and suitable for primary healthcare and personal health monitoring scenarios.

[0076] As an 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 signals include a cyclic square wave voltage signal, an AC excitation signal, and a zero-potential signal. The cyclic square wave voltage signal is used for cyclic voltammetry to detect ctDNA, controlling the electrode potential to fluctuate periodically to stimulate the ctDNA to undergo a redox reaction, generating a characteristic current and thus indicating its concentration. The AC excitation signal is used for electrochemical impedance spectroscopy to detect HCT, superimposing a small AC signal on a DC bias potential, which can be used to analyze the impedance characteristics of the sample, indicating the HCT value through changes in the amplitude and phase of the signal. The zero-potential signal is used for open-circuit potential method to detect pH, without applying an external potential, keeping the electrode in a naturally open-circuit state, and can indicate the concentration of hydrogen ions.

[0078] As an optional implementation, 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 sheet electrode, and a hydrogen ion selective electrode. The gold electrode serves as the working electrode, directly contacting the sample to be tested and promoting the redox reaction of the target analyte. The silver chloride electrode serves as the reference electrode, providing a stable reference potential for precise control of the working electrode's potential. The platinum sheet electrode serves as the counter electrode, completing the current loop and balancing the charge flow in the electrolytic cell. The hydrogen ion selective electrode serves as the working electrode, specifically designed for detecting hydrogen ion concentration and exhibiting high selectivity for hydrogen ions.

[0080] As a further optional implementation, the signal conversion module includes a synchronous sampling submodule, a current-to-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.

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

[0082] Commercial metal electrodes were selected as the base electrodes, and the commercial metal electrodes were pretreated.

[0083] A polyaniline conductive interlayer solution was prepared by using aniline monomer, ammonium persulfate, polyvinyl alcohol, and sulfuric acid solution.

[0084] An ion-sensitive membrane solution was prepared by using cyclohexanone, dioctyl sebacate, potassium tetra(4-chlorophenyl)borate, carboxylated polyvinyl chloride and a hydrogen ion carrier.

[0085] A polyaniline conductive interlayer solution is coated onto the surface of a commercial metal electrode to form a conductive interlayer;

[0086] An ion-sensitive membrane solution is coated onto the surface of a conductive intermediate layer to form a sensitive membrane layer, thus obtaining a hydrogen ion selective electrode.

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

[0088] Metal electrodes typically possess high conductivity and chemical inertness, enabling them to react with a variety of ions. However, this non-selective surface characteristic means that gold working electrodes exhibit similar affinities for different ions in electrochemical reactions, making it difficult to distinguish between different ion types. Therefore, electrode modification is necessary. A schematic diagram of the modified hydrogen ion selective electrode is shown below. Figure 4 As shown, the outermost layer is a hydrogen ion sensitive membrane (white layer), the middle layer is a conductive polyaniline (PANI) layer, and the base layer is a gold electrode (GE).

[0089] The sensitive membrane is the core of the ion-selective electrode. This membrane can convert the activity of a specific ion into a potential signal. The preparation process of the hydrogen ion-selective outer membrane is described below:

[0090] Table 1 shows the formulation of the outer membrane for the hydrogen ion selective electrode. According to the formulation in Table 1, accurately weigh each reagent and add it sequentially to a clean and dried transparent screw-top glass bottle. The order of reagent addition is crucial and must be strictly followed according to the numerical sequence specified in the formulation.

[0091] Table 1

[0092] Serial Number Drug Name effect Theoretical weight (g) Actual weight (g) 1 Cyclohexanone solvent 2.5 2.5048 2 Dioctyl sebacate plasticizer 0.65 0.6554 3 Potassium tetra(4-chlorophenyl)borate Organic salt localizers 0.005 0.0045 4 Carboxylated polyvinyl chloride (1.8%) Membrane body 0.34 0.3435 5 Hydrogen ion carrier I Hydrogen ion carrier 0.05 0.0433

[0093] After adding all reagents, place a clean and dry magnetic stir bar into the screw-top bottle. Place the bottle on a thermostatic magnetic stirrer and premix for 10-15 minutes at room temperature (20-25℃). After premixing, adjust the temperature to 90-100℃ and stir continuously at this temperature for 1 hour. During this process, closely observe the state of the reaction system, paying particular attention to whether any particulate matter appears on the bottle walls. Ideally, a clear, transparent organic outer membrane solution without noticeable particles should be obtained at the end of the reaction. If any abnormalities are observed, such as turbidity or precipitation, the reaction conditions may need to be adjusted or the solution may need to be prepared again.

[0094] After the reaction is complete, the solution is cooled to room temperature. It is then subjected to ultrasonic treatment for 8-10 minutes in an ultrasonic cleaner. This step aims to remove residual microbubbles from the solution, further improving its homogeneity and stability. After this treatment, a clear, slightly viscous, oily solution should be obtained. This solution serves as the precursor for the outer membrane of the hydrogen ion selective electrode and can be directly used in subsequent electrode preparation processes.

[0095] The storage and use of organic outer membrane solutions must follow strict procedures to ensure their effectiveness and safety. Prepared solutions should be stored in a refrigerator or professional cold storage cabinet at 2-8°C, where they can typically be stored for 3 months. Before use, the solution should be removed from the refrigerated environment and thoroughly stirred at room temperature for 20-30 minutes to ensure a uniform temperature rise and complete mixing. Subsequently, it is recommended to perform ultrasonic treatment for 8-10 minutes; this step effectively removes tiny air bubbles and improves homogeneity. Before use, operators should carefully observe the appearance of the solution to ensure there are no abnormalities such as flocculent matter or precipitates. If any abnormalities are found, the batch of solution should be immediately discontinued, and a fresh solution should be prepared to ensure experimental or production quality.

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

[0097] PANI, as an important conductive polymer, possesses excellent electronic conductivity. Its addition can significantly improve the electronic conductivity of electrode materials, thereby improving the charge transfer efficiency between the electrode and electrolyte interface. The preparation of the polyaniline film solution is a precise, multi-step process requiring 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, then cooled to room temperature to obtain solution A. Next, 0.8 g of aniline monomer is added to a mixture of 10 mL of 1M sulfuric acid and 1 mL of 50% phytic acid, stirred at room temperature for 30 minutes, and then mixed with solution A to form solution B. Simultaneously, solution C is prepared by dissolving 0.8 g of ammonium persulfate (APS) in 10 mL of 1M sulfuric acid. Finally, solution B is poured into solution C, and stirring is continued for at least 6 hours until a stable dark green polyaniline film 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 preparing the conductive interlayer and ion-sensitive membrane, a polyaniline (PANI) conductive polymer is deposited on the pretreated gold electrode surface using a drop casting method as the electrode's interlayer. This step requires precise control of the PANI solution concentration and drop volume to ensure the formation of a uniform conductive layer with appropriate thickness. After drop casting, the electrode is placed in a clean, dust-free environment to air dry naturally, typically for several hours to a day, depending on the ambient temperature and humidity. Once the PANI layer is completely dry, a second drop casting is performed, carefully adding a pre-prepared ion-sensitive membrane solution on top of the PANI layer. This process also requires precise control of the drop volume and distribution to ensure the formation of a uniform sensitive membrane layer. Finally, the electrode is again placed in a controlled environment to air dry naturally, avoiding external factors such as dust and moisture that could affect the membrane's quality.

[0099] To compare the electron transport performance of bare gold electrodes and PANI-modified electrodes in detail, this invention employs electrochemical impedance spectroscopy (EIS) to investigate the electrodes. In the Nyquist plot, the semicircular diameter in the high-frequency region is related to the charge transfer resistance (Ro) of the electrode. ct This parameter is directly related to the electron transport capability of an electrode and is a key indicator for evaluating the electrode's electron transport capacity. By using ZSimpWin software to perform equivalent circuit fitting on the Nyquist (electrochemical impedance spectroscopy) curves, the Re of each electrode can be determined. ct Values. Comparison of electrochemical impedance spectroscopy plots is shown below. Figure 5 As shown, Figure 5 The top left corner shows the equivalent circuit model, where R s W1 is the solution resistance, CPE (Constant Phase Element) is the constant phase element, and W1 is the diffusion resistance. Figure 5The impedance data of the unmodified gold electrode (GE) was used to simulate the electrochemical behavior of the electrode / electrolyte interface. The black curve (GE) 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 in the electrode's charge transfer capability. Specifically, the Re of the bare gold electrode (GE) is... ct The value is 677.3 Ω, while the R of the PANI-modified electrode is... ct The resistance was significantly reduced to 92.31 Ω. This huge difference clearly demonstrates that PANI modification significantly enhances the charge transfer efficiency of the electrode and reduces the charge transfer resistance. The PANI electrode has a smaller Ro. ct The value indicates that it has optimal electron transport capability, which may be attributed to PANI's conductivity and large specific surface area, providing favorable conditions for rapid electron transfer at the electrode / electrolyte interface.

[0100] As an optional further implementation, the indicator to be detected is the concentration of circulating tumor genes, and the second detection result is obtained through 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 as the reference electrode, and a platinum sheet electrode as the counter electrode.

[0103] The potentials of the gold electrode and the silver chloride electrode are controlled by the constant potential module based on the cyclic square wave voltage signal.

[0104] A second current response signal is generated through the gold electrode;

[0105] The second current response signal is converted into a first voltage response signal through a current-to-voltage conversion submodule;

[0106] The first voltage response signal is converted into a first digital response signal using an analog-to-digital converter;

[0107] The core control module plots an volt-ampere curve based on the first digital response signal and the cyclic square wave voltage signal. The relationship between the peak current in the volt-ampere curve and the concentration of circulating tumor genes is calculated using a preset first fitting model to obtain the second detection result.

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

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

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

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

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

[0113] (4) 1 mmol / L ferrocene solution and 0.1 mol / L potassium chloride solution were selected as electrolytes. A blank group was used, with samples without plasma DNA. Under the above measurement conditions, cyclic square wave voltammetry was used to sequentially perform electrochemical measurements on the blank group and plasma DNA samples. At this time, the signal output by the MCU control signal conditioning module was a cyclic square wave voltage signal. The constant voltage module controlled the potentials of the working electrode and reference electrode to change periodically in the form of a cyclic square wave. Specifically, the potential shifted positively and negatively above and below a certain reference potential with a small amplitude square wave signal, continuously stimulating the electrode interface reaction. The gold electrode reacted with the ctDNA in the sample to generate a corresponding response current. The response current signal was converted into a voltage signal by the IV conversion module. The ADC acquired the voltage signal and transmitted it to the MCU. The MCU calculated the detection result of the ctDNA concentration using the relationship model between the characteristic peak of the voltammetry curve and the ctDNA concentration. The resulting cyclic square wave voltammetry comparison curve is shown below. Figure 6 As shown, the black curve represents the measurement results of the conventional equipment, and the red curve represents the measurement results of the embodiment of the present invention. The shapes, peak currents, and peak potentials of the two curves are very similar, indicating that the performance of the two equipments is similar.

[0114] (5) Read the characteristic peak current of the plasma DNA sample within the range of 0.25V to 0.35V, process it, and obtain the results as follows: Figure 7 As shown, Figure 7Box plots showing the current signal distribution in cancer and normal samples.

[0115] As a further optional implementation, the indicator to be detected is hematocrit, and the third detection result is obtained through 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 as the reference electrode, and a platinum sheet electrode as the counter electrode.

[0118] The potentials of the gold electrode and the silver chloride electrode are controlled by a constant potential module based on an AC excitation signal.

[0119] A third current response signal is generated through gold electrodes;

[0120] The third current response signal is converted into a second voltage response signal through a current-to-voltage conversion submodule;

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

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

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

[0124] Specifically, in this embodiment of the invention, the electrode is configured with an area of ​​3.14 mm². 2 Gold working electrode, Ag / AgCl reference electrode, platinum sheet counter electrode, electrochemical impedance spectroscopy experimental parameters as follows: Figure 8 As shown, DC Voltage (V) is a constant DC potential, set to 0V relative to the open circuit potential (EOC). AC Voltage (mV pp) is the amplitude of the applied small AC signal, expressed as peak-to-peak (pp), with a value of 10mV. Initial Frequency (Hz) is the experimental starting frequency, measured in Hertz (Hz), with a value of 10. 5 Hz. FinalFrequency (Hz) is the experimental starting frequency, with a value of 1Hz. Points / decade is the number of sampling points for each order of magnitude frequency, with a value of 10. Initial Delay is the delay time before the experiment begins, in seconds, with a value of 5.

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

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

[0127] (2) Impedance spectroscopy testing was performed according to the above parameters and electrodes. At this time, the signal output by the MCU control signal conditioning module was an AC excitation signal. The constant voltage module maintained the potential between the working electrode and the reference electrode at a specific DC bias potential, while simultaneously superimposing a small AC excitation signal. Under these conditions, the impedance characteristics of the red blood cells in the sample to the electrolyte solution affected the phase and amplitude of the response current. The excitation signal and response voltage signal were synchronously acquired through the synchronous sampling submodule, and the synchronous sampling analog-to-digital converter (ADC) was used for the analysis.

[0128] The sampled data is de-DC biased and amplified, and then subjected to 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 formula for calculating the impedance phase angle θ of an electrolytic cell is:

[0132] θ = θ2 - θ1

[0133] Where RTIA is the resistance 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] Calculate the impedance and phase angle at the current frequency based on the obtained amplitude and phase angle, and then perform impedance measurement at the next frequency until the impedance spectrum measurement of the experimental frequency range is completed.

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

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

[0137] As an optional further implementation, the indicator to be detected is hydrogen ion concentration, and the fourth detection result is obtained through 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 by the constant potential module based on the zero potential signal.

[0141] The open-circuit potential between the hydrogen ion selective electrode and the silver chloride electrode is used as the fourth current response signal.

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

[0143] The third voltage response signal is converted into a second digital response signal using an analog-to-digital converter;

[0144] The core control module calculates the relationship between the second digital response signal and the hydrogen ion concentration based on the preset third fitting model, and obtains the fourth detection result.

[0145] Specifically, in this embodiment, after fabricating the electrode and characterizing it to demonstrate its reliability, the sensitivity of the electrode in detecting hydrogen ion concentration was investigated. The electrode was immersed in PBS (phosphate buffer) solutions with different pH values ​​(pH = 4.00–9.00) for 10 seconds to ensure sufficient contact between the electrode surface and the test solution. Open-circuit potential (OCP) was then recorded. The response current signal under this state was converted into a voltage signal using an IV conversion module. The ADC acquired the voltage signal and transmitted it to the MCU. The obtained open-circuit potential (OCP) response curve of the hydrogen ion selective electrode and the linear fitting relationship between pH and OPC are shown below. Figure 11 As shown. Combined with Figure 11 It can be seen that as 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 there is a good linear relationship between ocp and PH.

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

[0149] Reference Figure 12This invention provides a control method for an electrochemical analysis and detection device, which is used to implement the above-mentioned electrochemical analysis and detection device, and includes the following steps:

[0150] S101. Obtain the indicator to be detected through the input / output module;

[0151] S102. The core control module controls the input signal generation module to generate an excitation signal according to the index to be detected.

[0152] S103. The potential of the electrode module is controlled by the constant potential module according to the excitation signal;

[0153] S104. An electrochemical reaction is carried out between the electrode module and the sample to be tested to generate the first current response signal.

[0154] S105. An electrolytic cell is used to house the electrode module and the sample to be tested, providing a site for electrochemical reactions.

[0155] S106. The excitation signal and the first current response signal are sampled and converted by the signal conversion module to generate a digital signal;

[0156] S107. The core control module generates the first detection result based on the digital signal and the excitation signal.

[0157] It is understood that the content of the above system embodiments is applicable to this method embodiment. The specific functions implemented in this method embodiment are the same as those in the above system embodiments, and the beneficial effects achieved are also the same as those achieved in the above system embodiments.

[0158] It should be recognized that embodiments of the present invention can be implemented or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable storage medium. The methods described above can be implemented using standard programming techniques—including implementation in a computer program on a non-transitory computer-readable storage medium configured to allow the computer to operate in a specific and predefined manner—according to the methods and drawings described in the specific embodiments. Each program can be implemented in a high-level procedural or object-oriented programming language to communicate with the computer system. However, if desired, the program can be implemented in assembly or machine language. In any case, the language can be a compiled or interpreted language. Furthermore, for this purpose, the program can run on a programmed application-specific integrated circuit (ASIC).

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

[0160] Furthermore, the above methods can be implemented in any suitable type of computing platform, including but not limited to personal computers, minicomputers, mainframes, workstations, networked or distributed computing environments, standalone or integrated computer platforms, or in communication with charged particle tools or other imaging devices, etc. Aspects of the invention can be implemented as 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, optical read and / or write storage medium, RAM, ROM, etc., such that it is readable 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 processes described herein. Furthermore, the machine-readable code, or portions thereof, can be transmitted via wired or wireless networks. The invention described herein includes these and other different types of non-transitory computer-readable storage media when such media comprises instructions or programs that implement the steps described above in conjunction with a microprocessor or other data processor. When programmed according to the methods and techniques described in the invention, the invention also includes the computer itself.

[0161] A computer program can be applied to input data to perform the functions described herein, thereby transforming the input data to generate output data stored in 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 invention, the transformed data represents physical and tangible objects, including a specific visual depiction of physical and tangible objects generated on the display.

[0162] The above are merely preferred embodiments of the present invention. The present invention is not limited to the above-described embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention, as long as they achieve the technical effects of the present invention by the same means, should be included within the scope of protection of the present invention. Within the scope of protection of the present invention, the technical solutions and / or implementation methods can have various modifications and variations.

Claims

1. An electrochemical analysis and detection device, characterized in that, The system 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 both connected to the electrolytic cell. The input / output module is used to acquire the 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 the sample to be tested to generate a first current response signal. The electrolytic cell is used to contain the electrode module and the sample to be tested and provide a site for electrochemical reaction. The signal conversion module is used to sample and convert the excitation signal and the first current response signal to generate a digital signal. The core control module is also used to generate a first detection result according to the digital signal and the excitation signal. The indicator to be detected is one of circulating tumor gene concentration, hematocrit, and hydrogen ion concentration. The excitation signal is one of cyclic square wave voltage signal, AC excitation signal, and zero potential signal. The electrode module includes a gold electrode, a silver chloride electrode, a platinum sheet electrode, and a hydrogen ion selective electrode. The signal conversion module includes a synchronous sampling submodule, a current-to-voltage conversion submodule, an analog-to-digital converter, and a synchronous sampling analog-to-digital converter; the digital signal includes a digital response signal and a synchronous sampling digital response signal. The indicator to be detected is the concentration of circulating tumor genes, and the second detection result is obtained through the following steps: The core control module controls the input signal generation module to generate the cyclic square wave voltage signal. The gold electrode is used as the working electrode, the silver chloride electrode is used as the reference electrode, and the platinum sheet electrode is used as the counter electrode. The constant potential module controls the potentials of the gold electrode and the silver chloride electrode according to the cyclic square wave voltage signal; A second current response signal is generated through the gold electrode; The second current response signal is converted into a first voltage response signal through the current-to-voltage conversion submodule; The first voltage response signal is converted into a first digital response signal by the analog-to-digital converter; The core control module plots an volt-ampere curve based on the first digital response signal and the cyclic square wave voltage signal, and calculates the relationship between the peak current in the volt-ampere curve and the concentration of the circulating tumor gene using a preset first fitting model to obtain the second detection result. The indicator to be detected is the hematocrit, and the third detection result is obtained through the following steps: The core control module controls the input signal generation module to generate the AC excitation signal; The gold electrode is used as the working electrode, the silver chloride electrode is used as the reference electrode, and the platinum sheet electrode is used as the counter electrode. The constant potential module controls the potentials of the gold electrode and the silver chloride electrode according to the AC excitation signal; A third current response signal is generated through the gold electrode; The third current response signal is converted into a second voltage response signal by the current-to-voltage conversion submodule; The amplitude and phase of the AC excitation signal and the second voltage response signal are acquired by the synchronous sampling submodule. The synchronous sampling analog-to-digital converter converts the amplitude and phase of the AC excitation signal and the second voltage response signal into the synchronous sampling digital response signal. The core control module plots an impedance spectrum curve based on the synchronously sampled digital response signal, and calculates the relationship between the impedance spectrum curve and the hematocrit based on a preset second fitting model to obtain the third detection result. The indicator to be detected is the hydrogen ion concentration, and the fourth detection result is obtained through the following steps: The core control module controls the input signal generation module to generate the zero potential signal; The hydrogen ion selective electrode is used as the working electrode and the silver chloride electrode is used as the reference electrode. The constant potential module controls the potentials of the hydrogen ion selective electrode and the silver chloride electrode based on the zero potential signal; The open-circuit potential between the hydrogen ion selective electrode and the silver chloride electrode is used as the fourth current response signal. The current-to-voltage conversion submodule converts the converted fourth current response signal into a third voltage response signal. The analog-to-digital converter converts the third voltage response signal into a second digital response signal. The core control module calculates the relationship between the second digital response signal and the hydrogen ion concentration based on a preset third fitting model to obtain the fourth detection result.

2. The electrochemical analysis and detection device according to claim 1, characterized in that, The hydrogen ion selective electrode is prepared by the following steps: Commercial metal electrodes were selected as the base electrodes, and the commercial metal electrodes were pretreated. A polyaniline conductive interlayer solution was prepared by using aniline monomer, ammonium persulfate, polyvinyl alcohol, and sulfuric acid solution. An ion-sensitive membrane solution was prepared by using cyclohexanone, dioctyl sebacate, potassium tetra(4-chlorophenyl)borate, carboxylated polyvinyl chloride and a hydrogen ion carrier. The polyaniline conductive intermediate film solution is coated onto the surface of the commercial metal electrode to form a conductive intermediate layer; The ion-sensitive membrane solution is coated onto the surface of the conductive intermediate layer to form a sensitive membrane layer, thereby obtaining the hydrogen ion selective electrode.

3. A control method for an electrochemical analysis and detection device, used to implement the electrochemical analysis and detection device as described in any one of claims 1 to 2, characterized in that, Includes the following steps: The indicator to be detected is obtained through the input / output module; The core control module controls the input signal generation module to generate an excitation signal based on the indicator to be detected. The constant potential module controls the potential of the electrode module according to the excitation signal; The electrode module reacts electrochemically with the sample to be tested to generate a first current response signal. The electrolytic cell houses the electrode module and the sample to be tested, providing a site for electrochemical reactions. The signal conversion module samples and converts the excitation signal and the first current response signal to generate a digital signal. The core control module generates a first detection result based on the digital signal and the excitation signal. The indicator to be detected is one of circulating tumor gene concentration, hematocrit, and hydrogen ion concentration; the excitation signal is one of circulating square wave voltage signal, AC excitation signal, and zero potential signal; the electrode module includes a gold electrode, a silver chloride electrode, a platinum sheet electrode, and a hydrogen ion selective electrode. The signal conversion module includes a synchronous sampling submodule, a current-to-voltage conversion submodule, an analog-to-digital converter, and a synchronous sampling analog-to-digital converter; the digital signal includes a digital response signal and a synchronous sampling digital response signal. The indicator to be detected is the concentration of circulating tumor genes, and the second detection result is obtained through the following steps: The core control module controls the input signal generation module to generate the cyclic square wave voltage signal. The gold electrode is used as the working electrode, the silver chloride electrode is used as the reference electrode, and the platinum sheet electrode is used as the counter electrode. The constant potential module controls the potentials of the gold electrode and the silver chloride electrode according to the cyclic square wave voltage signal; A second current response signal is generated through the gold electrode; The second current response signal is converted into a first voltage response signal through the current-to-voltage conversion submodule; The first voltage response signal is converted into a first digital response signal by the analog-to-digital converter; The core control module plots an volt-ampere curve based on the first digital response signal and the cyclic square wave voltage signal, and calculates the relationship between the peak current in the volt-ampere curve and the concentration of the circulating tumor gene using a preset first fitting model to obtain the second detection result. The indicator to be detected is the hematocrit, and the third detection result is obtained through the following steps: The core control module controls the input signal generation module to generate the AC excitation signal; The gold electrode is used as the working electrode, the silver chloride electrode is used as the reference electrode, and the platinum sheet electrode is used as the counter electrode. The constant potential module controls the potentials of the gold electrode and the silver chloride electrode according to the AC excitation signal; A third current response signal is generated through the gold electrode; The third current response signal is converted into a second voltage response signal by the current-to-voltage conversion submodule; The amplitude and phase of the AC excitation signal and the second voltage response signal are acquired by the synchronous sampling submodule. The synchronous sampling analog-to-digital converter converts the amplitude and phase of the AC excitation signal and the second voltage response signal into the synchronous sampling digital response signal. The core control module plots an impedance spectrum curve based on the synchronously sampled digital response signal, and calculates the relationship between the impedance spectrum curve and the hematocrit based on a preset second fitting model to obtain the third detection result. The indicator to be detected is the hydrogen ion concentration, and the fourth detection result is obtained through the following steps: The core control module controls the input signal generation module to generate the zero potential signal; The hydrogen ion selective electrode is used as the working electrode and the silver chloride electrode is used as the reference electrode. The constant potential module controls the potentials of the hydrogen ion selective electrode and the silver chloride electrode based on the zero potential signal; The open-circuit potential between the hydrogen ion selective electrode and the silver chloride electrode is used as the fourth current response signal. The current-to-voltage conversion submodule converts the converted fourth current response signal into a third voltage response signal. The analog-to-digital converter converts the third voltage response signal into a second digital response signal. The core control module calculates the relationship between the second digital response signal and the hydrogen ion concentration based on a preset third fitting model to obtain the fourth detection result.

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