Sensing detection and drug delivery integrated platform, needle tube array and method

Abstract

The invention discloses a sensing detection and drug delivery integrated platform, a needle tube array and a method. According to the method for integrally preparing the electrodes with the independent functions through dimension reduction machining, the complexity of a three-dimensional micromachining technology and mutual interference of the electrodes with the different functions in the machining process are effectively avoided. On the basis of a second-generation glucose sensing electrode, a mediator-enhanced micro needle tube sensing electrode is constructed, and high-sensitivity and wide-detection-range specific response to blood glucose fluctuation in subcutaneous tissue fluid is achieved. A micro-needle diagnosis and treatment integrated platform integrating sensing detection and a drug delivery module is constructed, a diabetes animal model is utilized, four key physiological parameters such as blood sugar, keto acid, lactic acid and pH in a subcutaneous microenvironment are explored in situ and monitored in real time, and a controllable drug delivery method is adopted, so that a safe, painless transdermal and drug delivery mechanism of the micro-needle tube array is further verified; and a new path is provided for detection, early warning and treatment of acute complications of diabetes mellitus.

Description

Technical Field

[0001] The present invention relates to the technical field of microneedle sensing and drug delivery, and in particular to a sensing detection and drug delivery integrated platform, a needle tube array and a method. Background Art

[0002] At present, non-invasive or minimally invasive physiological signal monitoring methods that rely on new materials and cutting-edge technologies for in-situ detection of physiological parameters in the human body have become the focus of research internationally. Various innovative non-invasive detection technologies have emerged, including sweat detection, near-infrared spectroscopy detection, tear detection, saliva detection, and detection methods based on counterion phoresis. However, there are significant differences between the concentrations of physiological indicators in body fluids such as sweat, tears, and saliva and those in subcutaneous tissue fluid and blood, so there may be large deviations when measuring fluctuations in actual physiological parameters. As for non-invasive detection methods such as near-infrared spectroscopy and counterion phoresis, they have not yet reached the accuracy required for clinical testing, so they have not yet been applied in the field of clinical monitoring.

[0003] In recent years, minimally invasive painless subcutaneous detection and treatment technology based on microneedle arrays has achieved fruitful results in research and application. Painless subcutaneous drug delivery through microneedle arrays can effectively avoid the adverse factors such as pain, bleeding and infection caused by traditional metal needles. Microneedle painless drug delivery system has provided new ideas for the cure of many diseases, such as vaccine delivery, insulin supplementation, hypertension drugs, diet pills, contraceptives and analgesics. In addition, microneedles have also demonstrated innovative performance in minimally invasive biomedical sensing and can be used for the detection of various biomarkers, such as subcutaneous blood glucose, protein, reactive oxygen species, etc.

[0004] However, the existing microneedle-based electrode sensing-drug delivery diagnostic and therapeutic devices usually adopt the form of separate sensing detection module and drug delivery module, which makes it difficult to quickly and effectively feedback the detection effect; and micro-involvement drug delivery technology, such as non-invasive ion electrophoresis technology, is difficult to achieve rapid and instantaneous transdermal drug delivery due to the barrier effect of the skin stratum corneum to the external environment; at the same time, traditional microneedle transdermal technology usually cannot directly control drug delivery through electric fields; in addition, the sensing area of ​​the microneedle needle is limited, resulting in low detection sensitivity, and the low oxygen content in the microenvironment in the body also limits its detection range. Therefore, how to achieve minimally invasive transdermal drug delivery while avoiding pain, inconvenience and infection, and effectively integrate the sensing detection module that collects biophysiological parameters, deliver drugs to the subcutaneous in a controllable manner, and maintain good biosafety and therapeutic effects, is a major problem in the development of this technology. Summary of the invention

[0005] In view of this, embodiments of the present invention provide a sensing detection and drug delivery integrated platform, a needle tube array and a method.

[0006] The first aspect of the present invention provides an integrated sensing detection and drug delivery platform, comprising a detection module, a microcontroller and a drug delivery module; The detection module includes a microneedle tube electrode array, which is used to measure biological parameters of subcutaneous tissue of a living body and send the measured biological parameters to a microcontroller; the biological parameters specifically include blood sugar, ketoacid, lactic acid and pH value; The microcontroller includes a signal conditioning circuit and a microprogram control unit; the signal conditioning circuit is electrically connected to the detection module and the drug delivery module, and performs signal transmission between the detection module, the microcontroller and the drug delivery module; the microprogram control unit is used to output physiological index data, warning signals and drug delivery signals according to the biological parameters measured by the detection module; The drug delivery module includes a liquid reservoir, an infusion pump, a microfluidic chamber and an injection needle; the output end of the liquid reservoir and the input end of the microfluidic chamber are connected through the infusion pump; the output end of the microfluidic chamber is connected to the input end of the injection needle; the needle tip of the injection needle serves as the output end and penetrates into the subcutaneous tissue of the organism; wherein the liquid reservoir is used to store the drug to be delivered; the infusion pump is used to control the delivery speed of the drug according to the drug delivery signal of the microcontroller; and the injection needle is used to deliver the drug to the subcutaneous tissue of the organism.

[0007] Furthermore, the injection needle tube is integrated into the microneedle tube electrode array.

[0008] Furthermore, a wireless communication module is integrated in the microcontroller, and the wireless communication module establishes a wireless connection with a wireless communication terminal; the microcontroller outputs the physiological indicator data and the warning signal to the wireless communication terminal through the wireless communication module.

[0009] The second aspect of the present invention provides a microneedle tube electrode array, which is applied to the integrated sensing detection and drug delivery platform described in the first aspect, and includes a working electrode, a counter electrode, a reference electrode and a pad; The working electrodes are used to measure electrical signals of corresponding biological parameters in the subcutaneous tissue of a living body, and specifically include blood glucose electrodes, ketoacid electrodes, lactate electrodes and pH electrodes; The counter electrode is used to form a loop with the working electrode; The reference electrode is used to provide a reference potential; The pad is used to fix the working electrode, the counter electrode, and the reference electrode and collect the electrical signal collected by the working electrode, and send the collected electrical signal to the microcontroller.

[0010] The third aspect of the present invention provides a method for preparing a microneedle tube electrode array, which is used to prepare the microneedle tube electrode array described in the second aspect, comprising the following steps: Obtain stainless steel substrate material; Laser cutting the stainless steel substrate material to obtain a stainless steel microneedle tube; The inner wall of the stainless steel microneedle tube is acid-washed with polymethyl methacrylate to obtain a microneedle tube electrode with an insulated inner wall; Electrochemically gold-plating the outer wall of the microneedle tube electrode to obtain a gold-plated microneedle tube electrode; The gold-plated microneedle tube electrode is divided into a first gold-plated microneedle tube electrode, a second gold-plated microneedle tube electrode and a third gold-plated microneedle tube electrode, wherein the first gold-plated microneedle tube electrode is used to prepare a counter electrode, the second gold-plated microneedle tube electrode is used to prepare a working electrode, and the third gold-plated microneedle tube electrode is used to prepare a reference electrode; Electrochemically platinum-plating the outer wall of the first gold-plated microneedle tube electrode to obtain a platinum electrode as a counter electrode; A sensing layer is constructed on the second gold-plated microneedle tube to obtain a blood glucose electrode, a ketoacid electrode, a lactic acid electrode and a pH electrode as working electrodes respectively; The outer wall of the third gold-plated microneedle tube electrode is coated with silver / silver chloride ink to obtain a silver / silver chloride-coated gold-plated microneedle tube electrode; Modifying a polyvinyl butyral restriction layer on the silver / silver chloride covered gold-plated microneedle tube electrode to obtain a reference electrode; The prepared working electrode, counter electrode and reference electrode are fixed on the pad as microneedle tube electrodes; The pad and the micro-needle electrode on the back of the pad are insulated using an ethyl acetate solution in which polymethyl methacrylate is dissolved; A microfluidic cavity negative film is prepared on the side of the microneedle tube electrode on the back of the pad, and a barrier layer is prepared on the top surface; polydimethylsiloxane is used to adhere the microfluidic cavity negative film to the barrier layer to obtain a microneedle tube electrode array.

[0011] Furthermore, the stainless steel base material is 0Cr18Ni9 stainless steel material.

[0012] A fourth aspect of the present invention provides a method for preparing a blood glucose electrode, which is used to prepare the blood glucose electrode described in the third aspect, comprising the following steps: preparing polymeric redox mediators; Plating platinum on the second gold-plated microneedle tube electrode to obtain a first blood glucose gold-plated microneedle tube electrode; A carbon nanotube-perfluorosulfonic acid reinforcement layer is constructed on the surface of the first blood glucose gold-plated microneedle tube electrode to form a three-dimensional cross-linked network, thereby obtaining a second blood glucose gold-plated microneedle tube electrode; blending the polymer redox mediator, the glucose oxidase solution and the glutaraldehyde solution to obtain a first mixed solution; The first mixed solution is coated on the surface of the second blood glucose gold-plated microneedle tube electrode by immersion coating to obtain a blood glucose electrode.

[0013] The fifth aspect of the present invention provides a method for preparing a ketoacid electrode, which is used to prepare the ketoacid electrode described in the third aspect, comprising the following steps: Coating a 1,10-phenanthroline-5,6-dione solution on the surface of a platinum electrode to obtain a first ketoacid platinum electrode; After the first ketoacid platinum electrode is dried, a second ketoacid platinum electrode is obtained; NAD + The solution, the hydroxybutyrate dehydrogenase solution and the glutaraldehyde solution are mixed to obtain a second mixed solution; After the second ketoacid platinum electrode is dried, the second mixed solution is applied to the surface of the platinum electrode by immersion coating to obtain a third ketoacid platinum electrode; After the third ketoacid platinum electrode is dried, a ketoacid electrode is obtained.

[0014] The sixth aspect of the present invention provides a method for preparing a lactic acid electrode, which is used to prepare the lactic acid electrode according to the third aspect, comprising the following steps: dissolving chitosan in an acetic acid solution to obtain a chitosan solution; dissolving carbon nanotubes in the chitosan solution to obtain a viscous solution; mixing the viscous solution with a lactate oxidase solution to obtain a chitosan / lactate oxidase / carbon nanotube solution; placing a platinum electrode in a sulfuric acid solution, and scanning the surface of the platinum electrode using cyclic voltammetry to remove impurities on the surface of the platinum electrode and activate the platinum electrode, thereby obtaining a first lactate platinum electrode; placing the first platinum lactate electrode in a mixed solution of ferric chloride, potassium chloride, potassium ferrocyanide and hydrogen chloride, and depositing a Prussian blue mediator layer on the surface of the first platinum lactate electrode using electrochemical cyclic voltammetry to obtain a second platinum lactate electrode; Applying a chitosan / lactate oxidase / carbon nanotube solution to the surface of the second lactate platinum electrode by immersion coating to obtain a third lactate platinum electrode; After the third platinum lactate electrode is dried, a lactic acid electrode is obtained.

[0015] A seventh aspect of the present invention provides a method for preparing a pH electrode, which is used to prepare the pH electrode described in the third aspect, comprising the following steps: dissolving polyaniline jade base in dimethyl sulfoxide solution to obtain pH polyaniline jade base membrane solution; The platinum electrode is immersed in a mixed solution of EDOT and NaPSS, and PEDOT:PSS is modified on the outer wall of the platinum electrode by electrochemical deposition to form an ion-electron conversion intermediate layer, thereby obtaining a first pH platinum electrode; The pH polyaniline jade base film solution is immersed and coated on the first pH platinum electrode to prepare a polyaniline jade base film on the surface of the first pH platinum electrode to obtain a second pH platinum electrode; After the second pH platinum electrode is dried, a third pH platinum electrode is obtained; Introducing gaseous HCL into the polyaniline jade-based film on the surface of the platinum electrode under a vacuum environment, converting the polyaniline jade-based film into a polyaniline jade salt, and obtaining a fourth pH platinum electrode; The fourth pH platinum electrode was cleaned and dried using deionized water and nitrogen respectively to obtain a pH electrode.

[0016] The embodiment of the present invention also discloses a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device can read the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the above method.

[0017] The embodiments of the present invention have the following beneficial effects: the present invention discloses a sensing detection and drug delivery integrated platform, needle tube array and method for preparing electrodes with independent functions through dimensionality reduction processing integration, which effectively avoids the complexity of three-dimensional micro-processing technology and the mutual interference of electrodes with different functions during processing. Based on the second-generation glucose sensor electrode, a mediator-enhanced microneedle tube sensing electrode is constructed to achieve high sensitivity and specific response to blood sugar fluctuations in subcutaneous tissue fluid with a wide detection range. And by constructing an integrated microneedle diagnosis and treatment platform that integrates sensing detection and drug delivery modules, using diabetic animal models, explore the in-situ, real-time monitoring of four key physiological parameters such as blood sugar, ketoacid, lactate, and pH in the subcutaneous microenvironment and the method of controllable drug delivery, further verify the mechanism of safe, painless transdermal and drug delivery of microneedle tube arrays, and provide a new path for the detection, early warning and treatment of acute complications of diabetes.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a schematic diagram of the structural composition of a sensing detection and drug delivery integrated platform of the present invention.

[0021] Figure 2 It is a schematic diagram of the process of integrating a microneedle tube electrode array into an integrated platform according to the present invention.

[0022] Figure 3 It is a schematic diagram of the structure of a microneedle tube electrode array of the present invention.

[0023] Figure 4 It is a flow chart of a method for preparing a microneedle tube electrode array of the present invention.

[0024] Figure 5 It is a flow chart of the method for preparing the blood glucose electrode of the present invention.

[0025] Figure 6 The present invention is a flow chart of the method for preparing a keto acid electrode.

[0026] Figure 7 It is a flow chart of the method for preparing the lactic acid electrode of the present invention.

[0027] Figure 8 It is a flow chart of the method for preparing a pH electrode of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] In order to solve the medical problems in the closed-loop diagnosis and treatment of acute diabetes, the embodiment of the present invention has developed an integrated platform for sensing detection and drug delivery with a minimally invasive structure, which realizes minimally invasive parallel, synchronous and continuous monitoring of multiple subcutaneous biological indicators and intelligent drug delivery. The embodiment of the present invention proposes a new micro-nano processing strategy, explores the preparation method of constructing independent sensing electrodes on the surface of microneedle tubes, and then explores the feasibility of this sensor based on multiple independent electrodes to synchronously monitor the four physiological parameters of blood glucose, ketoacid, lactate, and pH in the body, and uses polymer redox mediators to enhance the sensing performance of the electrodes, and verifies the mechanism of safe, painless transdermal, and controllable drug delivery of microneedle arrays, providing new technologies for the detection, early warning, and treatment of acute complications of diabetes. Construct an innovative microneedle tube multi-parameter sensing array to achieve minimally invasive, continuous, synchronous and parallel in vivo monitoring and effective treatment of fluctuations in four biochemical indicators: Specifically, Figure 1 As shown, the first embodiment of the present invention provides an integrated platform of sensing detection and drug delivery, including a detection module, a microcontroller and a drug delivery module.

[0030] Detection module: In the embodiment of the present invention, the detection of biological parameters of an organism is achieved using a microneedle tube electrode array. The microneedle tube electrode array is used to measure the biological parameters of the subcutaneous tissue of an organism and send the measured biological parameters to a microcontroller. In the embodiment of the present invention, the microneedle tube electrode array penetrates the skin in a minimally invasive manner to avoid contact with subcutaneous nerves to reduce pain in the organism. In the embodiment of the present invention, the microneedle tube electrode array constructs a three-electrode (working electrode, counter electrode and reference electrode) sensing system, and by constructing different sensing layers on the working electrode, the detection of biological parameters of an organism including blood sugar, ketoacid, lactic acid and pH value is achieved.

[0031] Microcontroller: The microcontroller in the embodiment of the present invention includes a signal conditioning circuit and a microprogram control unit. The signal conditioning circuit electrically connects the detection module and the drug delivery module, and performs signal transmission between the detection module, the microcontroller and the drug delivery module; the microprogram control unit is used to output physiological indicator data, early warning signals and drug delivery signals according to the biological parameters measured by the detection module. During the detection process, the analog signal transmitted by the detection module will be converted into a digital signal in the signal conditioning circuit of the microcontroller, and the microprogram control unit will reflect a variety of physiological indicator data of the organism through time division multiplexing. On the other hand, the delivery rate of the drug delivery module in the embodiment of the present invention is also controlled by the microcontroller. Therefore, the microcontroller in the embodiment of the present invention can collect and analyze the physiological indicator data of the detection module at a high speed, and at the same time, it can combine the microneedle tube electrode array to intelligently control the drug release through microfluidic regulation technology to achieve integrated diagnosis and treatment of acute diabetic complications.

[0032] In some embodiments, the microcontroller is also integrated with a wireless communication module such as a Bluetooth module, and a wireless connection is established with a wireless communication terminal such as a host computer through the wireless communication module. The microcontroller outputs physiological index data and warning signals to the wireless communication terminal through the wireless communication module, so that the wireless communication terminal can remotely monitor the biological parameters of the organism through the microcontroller and control the delivery efficiency of the drug delivery module, and continuously track the dynamic changes of multiple indicators in the subcutaneous microenvironment of diabetic complications of the organism. When the biological parameters of the organism exceed the predetermined level, the microcontroller will generate an alarm signal and output it to the wireless communication module, which can promptly remind the user to take corresponding intervention measures.

[0033] Drug delivery module: In the embodiment of the present invention, the drug delivery module includes a liquid reservoir, an infusion pump, a microfluidic chamber and an injection needle; the output end of the liquid reservoir and the input end of the microfluidic chamber are connected through the infusion pump; the output end of the microfluidic chamber is connected to the input end of the injection needle; the needle tip of the injection needle is used as the output end to penetrate the subcutaneous tissue of the organism; wherein, the liquid reservoir is used to store the drug to be delivered; the infusion pump is used to control the delivery speed of the drug according to the drug delivery signal of the microcontroller; the injection needle is used to deliver the drug to the subcutaneous tissue of the organism. In the embodiment of the present invention, the liquid reservoir stores therapeutic drugs such as insulin, and the drug delivery efficiency is controlled by the infusion pump.

[0034] In some embodiments, the injection needle used to inject drugs into the subcutaneous tissue of a living organism is integrated into the microneedle electrode array, so that the integrated operation of biological parameter detection and drug delivery can be achieved. At this time, the microfluidic chamber of the embodiment of the present invention is placed on the top of the microneedle electrode array. In order to prevent the microfluidic chamber from causing electrochemical interference to the microneedle electrode array, the embodiment of the present invention needs to prepare a microfluidic chamber negative membrane and a barrier layer on the side and top surface of the microneedle electrode. Specifically, Figure 2 As shown, an aluminum positive mold can be designed and molded with polydimethylsiloxane (PDMS) to prepare a microfluidic cavity negative mold and a thin barrier layer. PDMS is used to bond the negative mold and the barrier layer to form a microfluidic cavity. After the pipe opening of the injection needle is connected to the microfluidic cavity, the infusion tube is further used to connect the infusion pump to the microfluidic cavity, the infusion pump and the reservoir, and a closed-loop system diagnosis and treatment system can be formed.

[0035] The second embodiment of the present invention provides a microneedle tube electrode array, such as Figure 3 As shown, the integrated sensing detection and drug delivery platform used in the first aspect includes a working electrode (WE), a counter electrode (CE), a reference electrode (RE) and a pad.

[0036] Working electrode: In the embodiment of the present invention, the working electrode is used to measure the electrical signal of the corresponding biological parameter in the subcutaneous tissue of the organism. The working electrode used in the embodiment of the present invention specifically includes a blood glucose electrode, a ketoacid electrode, a lactate electrode and a pH electrode. By modifying different sensing layers on the electrode surface, the sensing detection effect of multiple biological parameters is achieved.

[0037] Counter electrode: In the embodiment of the present invention, the counter electrode is used to form a circuit with the working electrode.

[0038] Reference electrode: The reference electrode in the embodiment of the present invention is used to provide a reference potential.

[0039] Among the working electrodes used in the embodiments of the present invention, the blood glucose electrode, keto acid electrode and lactic acid electrode all need to construct a three-electrode system for detection, while the pH electrode only needs to construct a two-electrode system to complete the detection. Different working electrodes in the embodiments of the present invention can share the same counter electrode and reference electrode for parameter detection, or use different counter electrodes and reference electrodes to complete the detection, which is not limited in the embodiments of the present invention.

[0040] Pad: The pad in the embodiment of the present invention is used to fix the working electrode, the counter electrode, the reference electrode and collect the electrical signal collected by the working electrode, and send the collected electrical signal to the microcontroller. The pad in the embodiment of the present invention is a combination of an acrylic plate support structure and a polyimide flexible PI electrode. On the one hand, it fixes the microneedle tube electrode array, and on the other hand, it transmits the detected biological parameters to the microcontroller through the PI electrode interface.

[0041] The third embodiment of the present invention provides a method for preparing a microneedle tube electrode array, which is used to prepare the microneedle tube electrode array of the second embodiment. Figure 4 As shown, the following steps are included: Obtain stainless steel substrate material; Laser cutting the stainless steel substrate material to obtain a stainless steel microneedle tube; The inner wall of the stainless steel microneedle tube is acid-washed with polymethyl methacrylate to obtain a microneedle tube electrode with an insulated inner wall; Electrochemically gold-plating the outer wall of the microneedle tube electrode to obtain a gold-plated microneedle tube electrode; The gold-plated microneedle tube electrode is divided into a first gold-plated microneedle tube electrode, a second gold-plated microneedle tube electrode and a third gold-plated microneedle tube electrode, wherein the first gold-plated microneedle tube electrode is used to prepare a counter electrode, the second gold-plated microneedle tube electrode is used to prepare a working electrode, and the third gold-plated microneedle tube electrode is used to prepare a reference electrode; Electrochemically platinum-plating the outer wall of the first gold-plated microneedle tube electrode to obtain a platinum electrode as a counter electrode; A sensing layer is constructed on the second gold-plated microneedle tube to obtain a blood glucose electrode, a ketoacid electrode, a lactic acid electrode and a pH electrode as working electrodes respectively; The outer wall of the third gold-plated microneedle tube electrode is coated with silver / silver chloride ink to obtain a silver / silver chloride-coated gold-plated microneedle tube electrode; Modifying a polyvinyl butyral restriction layer on the silver / silver chloride covered gold-plated microneedle tube electrode to obtain a reference electrode; The prepared working electrode, counter electrode and reference electrode are fixed on the pad as microneedle tube electrodes; The pad and the micro-needle electrode on the back of the pad are insulated using an ethyl acetate solution in which polymethyl methacrylate is dissolved; A microfluidic cavity negative film is prepared on the side of the microneedle tube electrode on the back of the pad, and a barrier layer is prepared on the top surface; polydimethylsiloxane is used to adhere the microfluidic cavity negative film to the barrier layer to obtain a microneedle tube electrode array.

[0042] Specifically, the stainless steel substrate material used in the embodiment of the present invention is 0Cr18Ni9 (SUS304) stainless steel material. After the substrate material is cut by a laser cutting machine to obtain a stainless steel microneedle tube, polymethyl methacrylate (PMMA) is used to insulate the inner wall of the stainless steel microneedle tube to prevent electrochemical interference; then the microneedle tube electrode is plated with gold to construct an Au layer on the outer wall of the electrode. Electrochemical platinum is plated on the outer wall of the gold-plated microneedle tube electrode to obtain a microneedle tube counter electrode (platinum electrode). The sensing layer corresponding to various biological parameters is modified on the outer wall of the platinum electrode by immersion coating to prepare a microneedle tube working electrode. The specific preparation methods of various biological parameter detection electrodes will be described through the fourth to seventh embodiments. The outer wall of the gold-plated microneedle tube electrode is modified with Ag / AgCl ink and polyvinyl butyral (PVB) restriction layer to form a microneedle tube reference electrode. The microneedle tube three-electrode sensing system is composed of a working electrode, a counter electrode and a reference electrode.

[0043] After constructing the microneedle three-electrode sensing system, the microneedle electrodes can be connected to the electrochemical workstation for detection. The detection performance of the microneedle sensing electrode can be measured in a simulated liquid with a step-by-step increase and decrease in the detection index concentration, including the acquisition of CV curves and It characteristics and the linearity analysis of the current-detection index concentration relationship. Finally, a standard curve of index concentration-sensing signal intensity is established; through long-term measurements (1-24 hours), the overall stability and repeatability of the sensing system are explored.

[0044] After completing the construction of the microneedle tube three-electrode sensing system, the software can be used to pattern the acrylic plate support structure and the polyimide flexible PI electrode. The microneedle tube working electrode, counter electrode, and reference electrode are respectively combined with the acrylic plate and the flexible PI circuit board to integrate the microneedle tube array, and the silver wire connecting the microneedle tube electrode and the PI electrode pad is coated and fixed with silver glue. The pad and the back of the electrode are insulated with PMMA solution to form the required microneedle tube electrode array.

[0045] A fourth embodiment of the present invention provides a method for preparing a blood glucose electrode, which is used to prepare the blood glucose electrode of the third embodiment. Figure 5 As shown, the following steps are included: preparing polymeric redox mediators; Plating platinum on the second gold-plated microneedle tube electrode to obtain a first blood glucose gold-plated microneedle tube electrode; A carbon nanotube-perfluorosulfonic acid reinforcement layer is constructed on the surface of the first blood glucose gold-plated microneedle tube electrode to form a three-dimensional cross-linked network, thereby obtaining a second blood glucose gold-plated microneedle tube electrode; blending the polymer redox mediator, the glucose oxidase solution and the glutaraldehyde solution to obtain a first mixed solution; The first mixed solution is coated on the surface of the second blood glucose gold-plated microneedle tube electrode by immersion coating method to obtain a blood glucose electrode.

[0046] The preparation of the blood glucose electrode in the embodiment of the present invention is divided into two parts: the preparation of the polymer redox mediator and the construction of the sensing layer: Preparation of polymer redox mediator: 8 mg of 2,2'-azobisisobutyronitrile and 2 mL of vinylpyrrolidone were added to 2 mL of deionized water and stirred at room temperature for about 20 minutes. After microwave heating for 3 minutes, 0.494 g of cis-bis(2,2'-bipyridine-N,N')dichloroosmium(II) (0.864 mmol) and 0.430 g of poly(4-vinyl-pyridine) (4.09 mmol) were added to 18 mL of ethylene glycol and heated under reflux for 2 hours under nitrogen. After cooling to room temperature, 30 mL of N,N-dimethylformamide (DMF) and 1.5 g of 2-bromoethylamine hydrobromide (7.3 mmol) were added and the solution was stirred at 45 °C overnight. After overnight, the solution was poured into rapidly stirred acetone to precipitate the crude polymer. The hygroscopic precipitate was collected, dissolved in deionized water, and filtered. Ammonium hexafluorophosphate solution (NH4PF6) was added for precipitation. After drying, 0.49 g of PF6-salt was dissolved in 20 mL of acetonitrile, diluted with 50 mL of deionized water, and stirred on a 5.2 g anion exchange column (chloride form) for 2 hours. The solution was filtered and evaporated to about 10 mL under vacuum. Concentrated hydrochloric acid was then added to adjust the pH to 2, and the solution was dropped into rapidly stirred acetonitrile to obtain the polymer redox mediator.

[0047] Construction of sensing layer: Single-walled carbon nanotube (SWCNT) aqueous solution and Nafion-117 ethanol solution were blended at a volume ratio of 4:1 (denoted as v / v), and electrochemically co-deposited on the surface of the gold-plated microneedle electrode to construct a carbon nanotube-perfluorosulfonic acid enhancement layer to form a three-dimensional cross-linked network. Glucose oxidase GOx solution, polymer redox mediator and glutaric dialdehyde (2.5%) solution were blended, and the polymer redox mediator was fixed on the outer wall of the gold-plated microneedle electrode by immersion coating to form a mediator-enhanced microneedle blood glucose sensing electrode.

[0048] The fifth embodiment of the present invention provides a method for preparing a ketoacid electrode, which is used to prepare the ketoacid electrode of the third embodiment. Figure 6 As shown, the following steps are included: Coating a 1,10-phenanthroline-5,6-dione solution on the surface of the second gold-plated microneedle tube electrode to obtain a first ketoacid gold-plated microneedle tube electrode; After the first ketoacid gold-plated microneedle tube electrode is dried, a second ketoacid gold-plated microneedle tube electrode is obtained; Mixing the NAD+ solution, the hydroxybutyrate dehydrogenase solution and the glutaraldehyde solution to obtain a second mixed solution; After the second ketoacid gold-plated microneedle tube electrode is dried, the second mixed solution is coated on the surface of the gold-plated microneedle tube electrode by immersion coating to obtain a third ketoacid gold-plated microneedle tube electrode; After the third ketoacid gold-plated microneedle electrode is dried, a ketoacid electrode is obtained.

[0049] Specifically, the preparation of the ketoacid electrode first requires the preparation of a 0.2% BSA 0.1 M Tris-HCL buffer solution, referred to as BSA solution; the NAD + The solution contained 0.5 M NAD + The hydroxybutyrate dehydrogenase solution is a BSA solution containing 5 mg / mL hydroxybutyrate dehydrogenase (HBD) and a 2.5% glutaraldehyde solution). First, apply a layer of 1,10-phenanthroline-5,6-dione (PD, concentration of 10 mg / mL) aqueous solution on the outer surface of the gold-plated microneedle electrode. After it is fully dried, NAD + (nicotinamide adenine dinucleotide (oxidized state)) solution, 5 mg / mL hydroxybutyrate dehydrogenase solution, and 2.5% glutaraldehyde solution were uniformly mixed in a volume ratio of 5:2:2, immersed and coated on the electrode surface, and dried at room temperature for at least 8 hours to obtain a hydroxybutyrate working electrode as a ketoacid electrode.

[0050] The sixth embodiment of the present invention provides a method for preparing a lactic acid electrode, which is used to prepare the lactic acid electrode of the third embodiment. Figure 7 As shown, the following steps are included: dissolving chitosan in an acetic acid solution to obtain a chitosan solution; dissolving carbon nanotubes in a chitosan solution to obtain a viscous solution; mixing the viscous solution with the lactate oxidase solution to obtain a chitosan / lactate oxidase / carbon nanotube solution; placing the second gold-plated microneedle tube electrode in a sulfuric acid solution, and scanning the surface of the gold-plated microneedle tube electrode using cyclic voltammetry to remove impurities on the surface of the gold-plated microneedle tube electrode and activate the gold-plated microneedle tube electrode, thereby obtaining a first lactic acid gold-plated microneedle tube electrode; The first lactic acid gold-plated microneedle tube electrode is placed in a mixed solution of ferric chloride, potassium chloride, potassium ferrocyanide and hydrogen chloride, and a Prussian blue mediator layer is deposited on the surface of the first lactic acid gold-plated microneedle tube electrode using electrochemical cyclic voltammetry to obtain a second lactic acid gold-plated microneedle tube electrode; The chitosan / lactate oxidase / carbon nanotube solution is coated on the surface of the second lactic acid gold-plated microneedle tube electrode by immersion coating to obtain a third lactic acid gold-plated microneedle tube electrode; After the third lactic acid gold-plated microneedle tube electrode is dried, a lactic acid electrode is obtained.

[0051] Specifically, 0.1 g of chitosan was first dissolved in 10 mL of 2% acetic acid, and the chitosan was completely dissolved by magnetic stirring for 1 h to obtain a clear 1% chitosan solution. Next, 2 mg of carbon nanotubes were added to 1 mL of 1% chitosan solution and ultrasonically stirred for 30 minutes to prepare a viscous solution. The viscous solution was mixed with a lactate oxidase solution (40 mg / ml in PBS, pH = 7.2) at a ratio of 1:1 (v / v) to prepare a chitosan / lactate oxidase / carbon nanotube solution. The electrode surface was scanned 20 times in a 0.1 M H2SO4 solution using cyclic voltammetry (voltage range 0.2 V to 1.2 V, scan speed 1 V / s) to remove impurities on the electrode surface and activate the electrode. Then, in a fresh solution containing 2.5 mM ferric chloride (FeCl3), 100 mM potassium chloride (KCl), 2.5 mM potassium ferrocyanide (K3Fe(CN)6), and 100 mM HCl, the Prussian blue mediator layer was deposited on the Au electrode by electrochemical cyclic voltammetry (voltage range of -0.15 V to 0.3 V, scan rate of 20 mV / s). Finally, 4 μL of chitosan / lactate oxidase / carbon nanotube solution was immersed and coated on the outer wall of the gold-coated microneedle electrode and dried overnight to obtain a lactate sensing electrode.

[0052] The seventh embodiment of the present invention provides a method for preparing a pH electrode, which is used to prepare the pH electrode of the third embodiment, such as Figure 8 As shown, the following steps are included: dissolving polyaniline jade base in dimethyl sulfoxide solution to obtain pH polyaniline jade base membrane solution; The second gold-plated microneedle tube electrode is immersed in a mixed solution of EDOT and NaPSS, and PEDOT:PSS is modified on the outer wall of the gold-plated microneedle tube electrode by electrochemical deposition to form an ion-electron conversion intermediate layer, thereby obtaining a first pH gold-plated microneedle tube electrode; The pH polyaniline jade base film solution is immersed and coated on the first pH gold-plated microneedle tube electrode to prepare the polyaniline jade base film on the surface of the first pH gold-plated microneedle tube electrode to obtain a second pH gold-plated microneedle tube electrode; After the second pH gold-plated microneedle tube electrode is dried, a third pH gold-plated microneedle tube electrode is obtained; In a vacuum environment, gaseous HCL is introduced into the polyaniline jade base film on the surface of the gold-plated microneedle tube electrode to convert the polyaniline jade base film into polyaniline jade salt to obtain a fourth pH gold-plated microneedle tube electrode; The fourth pH gold-plated microneedle tube electrode was cleaned and dried using deionized water and nitrogen respectively to obtain a pH electrode.

[0053] Specifically, 50 mg of polyaniline jade base was first dissolved in 20 mL of dimethyl sulfoxide (DMSO) to prepare the pH polyaniline jade base film solution for use. To ensure complete dissolution, the mixture was stirred and ultrasonicated for 24 hours, then left to stand for 24 hours to allow the undissolved particles to precipitate, and then the solution was slowly poured out. PEDOT and PSS were used as ion-electron conversion intermediate layers and deposited on the outer wall of the gold-plated microneedle electrode. 5 µL of pH polyaniline jade base film solution was immersed and coated on the surface of the working electrode and slowly dried overnight at room temperature. The film was then doped with 2 mL of concentrated HCl in a vacuum chamber for 5 h. The HCl fume caused by the low pressure in the vacuum chamber introduced H+ into the polyaniline jade base film, which was then converted into a polyaniline jade salt with higher conductivity. During the vacuum process, the color of the polyaniline jade base film changed from dark green to dark blue. Finally, the electrode was cleaned and dried with deionized water and nitrogen, respectively, to obtain a pH sensing electrode.

[0054] The technical improvements of the embodiments of the present invention include: 1) By constructing a microneedle electrode array, the skin is penetrated in a minimally invasive manner to avoid contact with the subcutaneous nerves to relieve pain. The outer wall of the microneedle tube is functionally modified to construct a three-electrode sensing system to achieve simultaneous detection of multiple parameters. Further use dimensionality reduction processing integration technology to develop a microneedle electrode array sensor to achieve sensing detection of multiple biochemical indicators, and deliver insulin through microneedles to lower blood sugar, so as to achieve the synergistic parallel of sensing detection and drug delivery.

[0055] 2) Construct mediator-enhanced blood glucose sensing electrode based on polymer redox. Combine polymer redox mediators with glucose oxidase to directly connect the enzyme active site with the sensing electrode, enhance the electron transfer efficiency, and reduce the working potential. Construct a carbon nanotube-perfluorosulfonic acid enhancement layer by electrochemical co-deposition, use the high specific surface area and strong conductivity of carbon nanotubes to improve the sensitivity of the blood glucose sensing electrode, and form a cross-linked network based on perfluorosulfonic acid to increase the fixation degree of the polymer redox mediator. 3) The sensing detection module and the drug delivery module are key modules in the integrated diabetes diagnosis and treatment system. The embodiment of the present invention constructs an integrated platform for sensing detection and drug delivery of acute diabetic complications based on microneedle electrode array sensors and microfluidic control technology. By developing sensor signal conditioning circuits and high-speed signal acquisition and data transmission microprocessors, biological parameter detection data is collected and analyzed at high speed, and combined with microneedle electrode arrays, drug release is intelligently controlled. Further relevant animal experiments will be carried out to fully explore the blood sugar regulation performance and in vivo biological safety of the integrated diagnosis and treatment system for acute diabetic complications.

[0056] As specific experimental data, the embodiment of the present invention places a microneedle tube multi-parameter sensor array on the back skin of a diabetic model rat, and delivers insulin into the subcutaneous part of the rat through a microneedle tube. At the same time, blood is collected from the tail vein and the blood glucose level of the rat is detected with a commercial blood glucose meter. The above measurement process is performed every 10 minutes, and the measurement is continued for 3 hours. The experiment is carried out for 2 days. The changes in the blood glucose level of the rat over time are tracked, and based on the changes in the amount of insulin delivered by the microneedle tube and the blood glucose concentration of the rat, the effectiveness of the microneedle tube multi-parameter sensor array for subcutaneous drug delivery, the delivery rate and other performance indicators, as well as the possible skin allergies, tissue fibrosis and inflammatory reactions are evaluated. There are 3 experimental groups, which are diabetic model rats (n>3). By comparing the concentrations of each indicator measured by the microneedle sensor array and the standard detection method, the anti-interference, sensitivity, sensitivity, stability, etc. of the three-dimensional microneedle array sensor for various detection indicators are evaluated. According to the sensing results, the degree of illness of the diabetic rat model is predicted, and by comparing the prediction results of the clinical indicators on the degree of illness of the rat, the diagnostic accuracy of the three-dimensional microneedle array sensor on the degree of illness of the acute diabetic rat model is evaluated.

[0057] Those skilled in the art will appreciate that the modules in the devices in the embodiments of the present invention may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments of the present invention may be combined into one module or unit or component, and in addition they may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the corresponding claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the corresponding claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0058] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0059] In addition, each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other. In particular, for embodiments such as devices and equipment, since they are basically similar to method embodiments, the relevant parts can refer to the partial description of the method embodiments. The embodiments of the devices and equipment described above are merely schematic, wherein the modules, units, etc. described as separate components may or may not be physically separated, that is, they may be located in one place, or they may be distributed in multiple places, such as nodes of a system network. Specifically, some or all of the modules and units may be selected according to actual needs to achieve the purpose of the above-mentioned embodiment scheme. Those skilled in the art can understand and implement it without paying creative labor.

[0060] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0061] In addition, the terms "first", "second", etc. used in the embodiments of the present invention are only used for descriptive purposes and should not be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated in the present embodiment. Therefore, the features defined by the terms "first", "second", etc. in the embodiments of the present invention can explicitly or implicitly indicate that the embodiment includes at least one of the features. In the description of the present invention, the word "multiple" means at least two or two or more, such as two, three, four, etc., unless otherwise clearly and specifically defined in the embodiments.

[0062] In the embodiments of the present invention, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element. In addition, components, features, and elements with the same name in different embodiments of the present invention may have the same meaning or different meanings, and their specific meanings need to be determined by their explanation in the specific embodiment or further combined with the context in the specific embodiment.

[0063] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and cannot be construed as limitations of the present invention, and those of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention. Those skilled in the art will readily come to think of other embodiments of the present invention after considering the specification and practicing the present invention. This application is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary technical means in the art that are not disclosed in the present invention. The specification and embodiments are intended to be exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

Claims

1. A sensor detection and drug delivery integrated platform, characterized in that: including a detection module, a microcontroller, and a drug delivery module; The detection module includes a microneedle tube electrode array, which is used to measure biological parameters of subcutaneous tissue of a living body and send the measured biological parameters to a microcontroller; the biological parameters specifically include blood sugar, ketoacid, lactic acid and pH value; The microcontroller includes a signal conditioning circuit and a microprogram control unit; the signal conditioning circuit is electrically connected to the detection module and the drug delivery module, and performs signal transmission between the detection module, the microcontroller and the drug delivery module; the microprogram control unit is used to output physiological index data, warning signals and drug delivery signals according to the biological parameters measured by the detection module; The drug delivery module includes a liquid reservoir, an infusion pump, a microfluidic chamber and an injection needle; the output end of the liquid reservoir and the input end of the microfluidic chamber are connected through the infusion pump; the output end of the microfluidic chamber is connected to the input end of the injection needle; the needle tip of the injection needle serves as the output end and penetrates into the subcutaneous tissue of the organism; wherein the liquid reservoir is used to store the drug to be delivered; the infusion pump is used to control the delivery speed of the drug according to the drug delivery signal of the microcontroller; and the injection needle is used to deliver the drug to the subcutaneous tissue of the organism.

2. The integrated sensing detection and drug delivery platform according to claim 1, characterized in that: The injection needle tube is integrated in the microneedle tube electrode array.

3. The integrated sensing detection and drug delivery platform according to claim 1, characterized in that: The microcontroller is also integrated with a wireless communication module, and the wireless communication module establishes a wireless connection with a wireless communication terminal; the microcontroller outputs the physiological indicator data and the warning signal to the wireless communication terminal through the wireless communication module.

4. A microneedle electrode array, applied to the integrated sensing detection and drug delivery platform as claimed in any one of claims 1 to 3, characterized in that: It includes a working electrode, a counter electrode, a reference electrode and a pad; The working electrodes are used to measure electrical signals corresponding to biological parameters in the subcutaneous tissue of a living body, and specifically include blood glucose electrodes, ketoacid electrodes, lactate electrodes, and pH electrodes; The counter electrode is used to form a loop with the working electrode; The reference electrode is used to provide a reference potential; The pad is used to fix the working electrode, the counter electrode, and the reference electrode and collect the electrical signal collected by the working electrode, and send the collected electrical signal to the microcontroller.

5. A method for preparing a microneedle tube electrode array, for preparing the microneedle tube electrode array as claimed in claim 4, characterized in that: The following steps are involved: Obtain stainless steel substrate material; Laser cutting the stainless steel substrate material to obtain a stainless steel microneedle tube; The inner wall of the stainless steel microneedle tube is acid-washed with polymethyl methacrylate to obtain a microneedle tube electrode with an insulated inner wall; Electrochemically gold-plating the outer wall of the microneedle tube electrode to obtain a gold-plated microneedle tube electrode; The gold-plated microneedle tube electrode is divided into a first gold-plated microneedle tube electrode, a second gold-plated microneedle tube electrode and a third gold-plated microneedle tube electrode, wherein the first gold-plated microneedle tube electrode is used to prepare a counter electrode, the second gold-plated microneedle tube electrode is used to prepare a working electrode, and the third gold-plated microneedle tube electrode is used to prepare a reference electrode; Electrochemically platinum-plating the outer wall of the first gold-plated microneedle tube electrode to obtain a platinum electrode as a counter electrode; A sensing layer is constructed on the second gold-plated microneedle tube to obtain a blood glucose electrode, a ketoacid electrode, a lactic acid electrode and a pH electrode as working electrodes respectively; The outer wall of the third gold-plated microneedle tube electrode is coated with silver / silver chloride ink to obtain a silver / silver chloride-coated gold-plated microneedle tube electrode; Modifying a polyvinyl butyral restriction layer on the silver / silver chloride covered gold-plated microneedle tube electrode to obtain a reference electrode; The prepared working electrode, counter electrode and reference electrode are fixed on the pad as microneedle tube electrodes; The pad and the micro-needle electrode on the back of the pad are insulated using an ethyl acetate solution in which polymethyl methacrylate is dissolved; A microfluidic cavity negative film is prepared on the side of the microneedle tube electrode on the back of the pad, and a barrier layer is prepared on the top surface; polydimethylsiloxane is used to adhere the microfluidic cavity negative film to the barrier layer to obtain a microneedle tube electrode array.

6. The method for preparing a microneedle tube electrode array according to claim 5, characterized in that: The stainless steel base material is 0Cr18Ni9 stainless steel material.

7. A method for preparing a blood glucose electrode, for preparing the blood glucose electrode as claimed in claim 5, characterized in that: The following steps are involved: preparing polymeric redox mediators; Plating platinum on the second gold-plated microneedle tube electrode to obtain a first blood glucose gold-plated microneedle tube electrode; A carbon nanotube-perfluorosulfonic acid reinforcement layer is constructed on the surface of the first blood glucose gold-plated microneedle tube electrode to form a three-dimensional cross-linked network, thereby obtaining a second blood glucose gold-plated microneedle tube electrode; blending the polymer redox mediator, the glucose oxidase solution and the glutaraldehyde solution to obtain a first mixed solution; The first mixed solution is coated on the surface of the second blood glucose gold-plated microneedle tube electrode by immersion coating to obtain a blood glucose electrode.

8. A method for preparing a ketoacid electrode, for preparing the ketoacid electrode as claimed in claim 5, characterized in that: The following steps are involved: Coating a 1,10-phenanthroline-5,6-dione solution on the surface of the second gold-plated microneedle tube electrode to obtain a first ketoacid gold-plated microneedle tube electrode; After the first ketoacid gold-plated microneedle tube electrode is dried, a second ketoacid gold-plated microneedle tube electrode is obtained; NAD + The solution, the hydroxybutyrate dehydrogenase solution and the glutaraldehyde solution are mixed to obtain a second mixed solution; After the second ketoacid gold-plated microneedle tube electrode is dried, the second mixed solution is applied to the surface of the gold-plated microneedle tube electrode by immersion coating to obtain a third ketoacid gold-plated microneedle tube electrode; After the third ketoacid gold-plated microneedle tube electrode is dried, a ketoacid electrode is obtained.

9. A method for preparing a lactic acid electrode, for preparing the lactic acid electrode as claimed in claim 5, characterized in that: The following steps are involved: dissolving chitosan in an acetic acid solution to obtain a chitosan solution; dissolving carbon nanotubes in the chitosan solution to obtain a viscous solution; mixing the viscous solution with a lactate oxidase solution to obtain a chitosan / lactate oxidase / carbon nanotube solution; placing the second gold-plated microneedle tube electrode in a sulfuric acid solution, and scanning the surface of the gold-plated microneedle tube electrode using cyclic voltammetry to remove impurities on the surface of the gold-plated microneedle tube electrode and activate the gold-plated microneedle tube electrode, thereby obtaining a first lactic acid gold-plated microneedle tube electrode; Placing the first lactic acid gold-plated microneedle tube electrode in a mixed solution of ferric chloride, potassium chloride, potassium ferrocyanide and hydrogen chloride, and depositing a Prussian blue mediator layer on the surface of the first lactic acid gold-plated microneedle tube electrode using electrochemical cyclic voltammetry to obtain a second lactic acid gold-plated microneedle tube electrode; Applying a chitosan / lactate oxidase / carbon nanotube solution to the surface of the second lactic acid gold-plated microneedle tube electrode by immersion coating to obtain a third lactic acid gold-plated microneedle tube electrode; After the third lactic acid gold-plated microneedle tube electrode is dried, a lactic acid electrode is obtained.

10. A method for preparing a pH electrode, for preparing the pH electrode as claimed in claim 5, characterized in that: The following steps are involved: dissolving polyaniline jade base in dimethyl sulfoxide solution to obtain pH polyaniline jade base membrane solution; The second gold-plated microneedle tube electrode is immersed in a mixed solution of EDOT and NaPSS, and PEDOT:PSS is modified on the outer wall of the gold-plated microneedle tube electrode by electrochemical deposition to form an ion-electron conversion intermediate layer, thereby obtaining a first pH gold-plated microneedle tube electrode; The pH polyaniline jade base film solution is immersed and coated on the first pH gold-plated microneedle tube electrode, and the polyaniline jade base film is prepared on the surface of the first pH gold-plated microneedle tube electrode to obtain a second pH gold-plated microneedle tube electrode; After the second pH gold-plated microneedle tube electrode is dried, a third pH gold-plated microneedle tube electrode is obtained; Introducing gaseous HCL into the polyaniline jade base film on the surface of the gold-plated microneedle tube electrode under a vacuum environment, converting the polyaniline jade base film into a polyaniline jade salt, and obtaining a fourth pH gold-plated microneedle tube electrode; The fourth pH gold-plated microneedle tube electrode was cleaned and dried using deionized water and nitrogen respectively to obtain a pH electrode.

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