Self-generated neural electrode and method of manufacturing the same

Abstract

The application belongs to the technical field of brain-computer interface, and provides a self-generated neural electrode, which comprises a flexible insulating base, a surface insulating layer arranged on the flexible insulating base, and a conductive metal layer arranged between the flexible insulating base and the surface insulating layer, wherein the conductive metal layer is patterned to form a neural recording electrode array and a micro biological fuel cell unit; a window is arranged on the surface insulating layer to expose electrode sites of the neural recording electrode array and at least part of an electrode surface of the micro biological fuel cell unit; a precursor storage structure is arranged at the exposed electrode sites of the neural recording electrode array, and the precursor storage structure contains a medium containing a first precursor; the micro biological fuel cell unit is configured to generate a micro current after being implanted into a living body, and drive the first precursor to generate an in-situ electrochemical reaction at an interface of the neural recording electrode array, so as to generate conductive nanoclusters, and effectively solve the pain point of signal attenuation caused by long-term implantation.

Description

Technical Field

[0001] This application belongs to the field of brain-computer interface technology, and more specifically, relates to a self-generated neural electrode and its manufacturing method. Background Technology

[0002] Invasive brain-computer interface (BCI) technology, with its superior spatiotemporal resolution, has revealed the mechanisms of neural signal generation and transmission at the cellular level, demonstrating enormous potential in fields such as medical rehabilitation, enhanced perception, and human-computer interaction. To meet the needs of future freely movable animal experiments and clinical applications, invasive BCI systems must not only possess the core characteristics of high throughput, low power consumption, and miniaturization, but also ensure signal stability in long-term implantation environments.

[0003] However, existing rigid or flexible neural probes, such as those based on silicon wafers, polyimide (PI), or parylene-C, inevitably lead to glial cell proliferation and the formation of "glial scars" encapsulating the electrodes after implantation into brain tissue due to mechanical mismatch at the electrode-tissue interface and foreign body reaction. This dense scar significantly increases interfacial impedance, reduces signal quality and charge transfer capacity, causing neurophysiological signals (Spikes and LFP) to decay or even disappear within weeks to months, limiting the stability and lifespan of the implanted device. Existing anti-scarring strategies mostly involve surface coating with anti-rejection drugs or conductive polymers, but these coatings are prone to degradation and detachment during long-term implantation, failing to achieve long-term, dynamic self-repair of the interface. Summary of the Invention

[0004] The purpose of this application is to provide a self-generating neural electrode to solve the technical problem in the prior art where, after a neural electrode is implanted into brain tissue, glial cell proliferation forms a "glial scar" that encapsulates the electrode, increasing the electrode interface impedance and limiting the stability and lifespan of the neural electrode.

[0005] To achieve the above objectives, a first aspect of this application provides a self-generated neural electrode, comprising: Flexible insulating substrate; A surface insulating layer disposed on the flexible insulating substrate; And a conductive metal layer disposed on the flexible insulating substrate and between the surface insulating layer, the conductive metal layer being patterned to form a neural recording electrode array and a micro biofuel cell unit; The surface insulating layer has windows to expose the electrode sites of the neural recording electrode array and at least a portion of the electrode surface of the micro biofuel cell unit.

[0006] Among them, a precursor storage structure is provided at the electrode sites of the exposed neural recording electrode array, and the precursor storage structure contains a medium containing a first precursor. The micro biofuel cell unit is configured to generate a microcurrent after implantation into a living organism, and drive the first precursor to undergo an in-situ electrochemical reaction at the interface of the neural recording electrode array to generate conductive nanoclusters.

[0007] In some possible implementations, the anode of the micro biofuel cell unit is modified with glucose oxidase.

[0008] In some possible implementations, the precursor storage structure contains a medium comprising a second precursor, which reacts with hydrogen peroxide to generate anti-inflammatory nanoclusters for inhibiting scar formation.

[0009] In some possible implementations, the second precursor includes a manganese ion complex and / or a cerium ion complex.

[0010] In some possible implementations, the precursor storage structure contains a medium comprising glucose oxidase.

[0011] In some possible implementations, the first precursor includes at least one of a chloroaurate complex, a platinum salt, or a 3,4-ethylenedioxythiophene (EDOT) monomer.

[0012] In some possible implementations, the precursor storage structure is a groove or cavity formed on the surface insulating layer.

[0013] In some possible implementations, the precursor storage structure is further covered by a barrier protective layer made of Parylene-C.

[0014] In some possible implementations, the conductive metal layer also forms an on-chip microcircuit, the micro biofuel cell unit and the neural recording electrode array are arranged side by side and electrically connected through the on-chip microcircuit.

[0015] To achieve the above objectives, a second aspect of this application provides a method for manufacturing a neural electrode as described in the first aspect and any optional implementation thereof, comprising: A sacrificial layer and a flexible insulating substrate are sequentially formed on the substrate; A conductive metal layer is deposited and patterned on the flexible insulating substrate using photolithography and etching processes to form the electrode patterns and connection traces of the neural recording electrode array and the micro biofuel cell unit. A surface insulating layer is formed covering the conductive metal layer; The electrode sites of the neural recording electrode array and the windows of the micro biofuel cell unit electrodes are exposed using photolithography and etching processes, and a precursor storage structure is formed at the electrode sites of the neural recording electrode array.

[0016] The electrodes of the micro biofuel cell unit are functionalized. A medium containing a first precursor is introduced into the precursor storage structure; The sacrificial layer is removed to release the device from the substrate.

[0017] In some possible implementations, the step of functionalizing the electrodes of the micro biofuel cell unit includes: The anode of the micro biofuel cell unit is modified by immobilizing glucose oxidase, and the cathode of the micro biofuel cell unit is modified by depositing or modifying oxygen reduction catalyst.

[0018] In some possible implementations, the step of introducing a medium containing the first precursor into the precursor storage structure includes: The mixed region containing the first precursor, the second precursor, glucose oxidase and hydrogel prepolymer is injected into the storage region and crosslinked by light or heat to solidify it into a hydrogel. A Parylene-C protective layer is vapor-deposited above the precursor storage structure.

[0019] The beneficial effects of the self-generated neural electrodes provided in this application are as follows: Compared with existing technologies, the self-generated neural electrode in this application utilizes a micro biofuel cell unit to continuously supply energy from endogenous glucose / oxygen and drives the electrochemical reaction of the precursor, enabling the electrode interface to continuously and dynamically grow new conductive nanoclusters after implantation. This actively counteracts the increase in interface impedance caused by colloid proliferation, fundamentally changing the passive situation of existing technologies that rely on static coatings and inevitably suffer from performance degradation, and solving the core problem of long-term signal stability. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A schematic diagram of the structure of an embodiment of the self-generated neural electrode provided in this application; Figure 2 A cross-sectional schematic diagram of the self-generated neural electrode provided in the embodiments of this application when it is not implanted in a biological body; Figure 3 This is a cross-sectional schematic diagram of a self-generated neural electrode implanted in a living organism after a period of time, as provided in an embodiment of this application. Detailed Implementation

[0022] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0023] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0024] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0026] Example 1: A self-generated neural electrode Specific reference Figures 1 to 3 , Figures 1 to 3 This is a schematic diagram of the structure of the self-generated neural electrode in Embodiment 1 of this application.

[0027] like Figure 1 As shown in the top view, the self-generated neural electrode includes a flexible insulating substrate 100, a micro biofuel cell unit 200, a neural recording electrode array 300, an on-chip microcircuit 400, a precursor storage structure 600, and a surface insulating layer 500.

[0028] The flexible insulating substrate 100 is made of a material with excellent flexibility and biocompatibility, making it suitable for implantation into living organisms, such as brain tissue. In this embodiment, the flexible insulating substrate 100 is made of polyimide (PI) with a thickness of approximately 2–5 μm, and can be prepared by spin-coating a polyamide acid (PAA) precursor solution followed by stepwise thermal imidization (90°C → 120°C → 250°C → 350°C). In some other embodiments, the flexible insulating substrate 100 may also be made of Parylene-C.

[0029] like Figure 2 or Figure 3 As shown, a patterned conductive metal layer 310 is disposed on the flexible insulating substrate 100. This conductive metal layer 310 has a two-layer structure of "transition layer-noble metal layer," and can be formed by magnetron sputtering or electron beam evaporation deposition. In this embodiment, the conductive metal layer 310 has a "chromium (Cr)-gold (Au)" two-layer structure, wherein the thickness of the chromium layer is 30 nm and the thickness of the gold layer is 300 nm. The chromium layer, as a transition layer, can increase the adhesion of the noble metal layer. In some other embodiments, combinations such as titanium (Ti)-gold or chromium-platinum (Pt) can also be used.

[0030] The conductive metal layer 310 is patterned using photolithography and etching processes to form multiple functional regions, including a neural recording electrode array 300 region, a micro-biofuel cell unit 200 region, and an on-chip microcircuit 400 region connecting the neural recording electrode array 300 region and the micro-biofuel cell unit 200 region. The neural recording electrode array 300 region contains multiple circular noble metal electrode sites for detecting neural electrical signals. The micro-biofuel cell unit 200 region includes an anode array 210 and a cathode array 220, each of which includes multiple electrode sites. The on-chip microcircuit 400 includes multiple wires for directly and precisely guiding the weak current generated by the micro-biofuel cell unit 200 to the surface of the neural recording electrode array 300, thereby driving an in-situ electrochemical reaction. This eliminates the dependence on external wires, making the entire system integrated, reliable, and self-driving.

[0031] Specifically, the micro biofuel cell unit 200 is an enzymatic glucose biofuel cell. The anode surface of the micro biofuel cell unit 200 is modified with a glucose oxidase (GOx) layer, which is cross-linked and fixed with glutaraldehyde and covered with a Nafion protective film. The cathode surface is modified with a platinum black catalyst layer formed by electrochemical deposition, which has a nanoflower-like morphology to efficiently catalyze the oxygen reduction reaction.

[0032] Furthermore, in this embodiment, to improve the operational stability and catalytic capability of the micro biofuel cell unit 200, when modifying glucose oxidase in the anode array, gold nanoparticles (AuNPs) were first deposited at the anode array 210, followed by drop-coating of a glucose oxidase (GOx) solution and cross-linking fixation with 1% glutaraldehyde, and finally covered with a Nafion protective film. The deposited gold nanoparticles increase the specific surface area of ​​the electrode and, on the other hand, form a synergistic effect with the natural enzyme GOx to improve catalytic capability. The Nafion protective film, by immobilizing the enzyme, selectively permeating reactants, eliminating interfering substances, and conducting protons, ensures that the micro biofuel cell anode can convert glucose chemical energy into weak electrical energy in a long-term, stable, and efficient manner in the complex biological in vivo environment. At the cathode array 220, a platinum black catalyst with an electrodeposition morphology of "nanoflower" is used, or laccase (or copper oxidase or bilirubin oxidase) is modified. The "nanoflower" shaped platinum black can further increase the specific surface area of ​​the electrode, greatly increasing the catalytic active area, and can optimize the mass transport pathway, improving the smooth discharge of reaction products.

[0033] In addition, a surface insulating layer 500 is disposed on the flexible insulating substrate 100 and the patterned conductive metal layer 310 of the neural electrode. The surface insulating layer 500 can also be made of polyimide material, which is formed by spin-coating polyamic acid again and imidizing it, with a thickness of about 7-12 μm. Windows are formed on the surface insulating layer 500 to expose each electrode site of the neural recording electrode array 300, the entire active region of the anode of the micro biofuel cell unit 200, and the entire active region of the cathode.

[0034] It should be noted that in this embodiment, a precursor storage structure 600 is provided at the electrode sites of the exposed neural recording electrode array 300, which is a window opened on the surface insulating layer 500.

[0035] Specifically, such as Figure 2 or Figure 3 As shown, the precursor storage structure 600 is specifically a groove or cavity structure defined by the window sidewall of the surface insulating layer 500. The precursor storage structure 600 is located above the neural recording electrode array 300. It utilizes the window in the surface insulating layer 500 to construct a precursor medium 700 containing nanoclusters for anchoring and accumulating the precursor medium 700. This structural design prevents the precursor medium 700 from being rapidly flushed away by cerebrospinal fluid in vivo, ensuring the persistence of in-situ growth.

[0036] In this embodiment, the precursor medium 700 is a crosslinkable hydrogel, which can use hyaluronic acid (HA) or polyethylene glycol diacrylate (PEG-DA) as the hydrogel matrix. In addition to the hydrogel matrix, the hydrogel also includes a first precursor.

[0037] Specifically, the first precursor can be at least one of a chloroauric acid complex, a platinum salt, or a 3,4-ethylenedioxythiophene (EDOT) monomer. After the neural electrodes are implanted into the organism, the micro-biofuel cell unit 200 spontaneously starts in the cerebrospinal fluid (glucose concentration approximately 1-5 mM). A weak open-circuit voltage is generated between the anode and cathode of the micro-biofuel cell unit 200. The on-chip microcircuit 400 applies this micro-potential to the neural recording electrode array 300. The precursor medium 700 is slowly electrochemically reduced over 7-14 days, and conductive nanoclusters with a particle size of 1-50 nm and a length of several to tens of micrometers grow outward along the electric field lines, successfully establishing a signal channel across glial scars. Compared with existing technologies that mostly adopt a "passive defense" strategy of pre-coating the probe surface with conductive polymers or anti-rejection drugs, the coating is easily degraded or detached over time after implantation, leading to a sharp increase in long-term impedance. This application introduces a micro-biofuel cell unit to directly utilize the continuous glucose and oxygen in the cerebrospinal fluid as fuel, converting it into weak electrical energy. Without requiring any external power supply or increasing the thermal load on the brain, conductive nanoclusters can be synthesized in situ on the electrode surface for several weeks or even months, transforming "static wear" into "dynamic growth," thus solving the problem of signal attenuation after long-term implantation.

[0038] In some embodiments, a gas barrier protective layer with a thickness of approximately 20–100 nm is also applied over the precursor storage structure 600 (i.e., the window filled with hydrogel). The gas barrier protective layer is made of parylene-C prepared by chemical vapor deposition (CVD) and is used to seal and protect the precursor hydrogel medium before implantation to prevent it from losing water or becoming contaminated.

[0039] In some embodiments, the precursor medium 700 may further include a second precursor material, which may be manganese chloride (MnCl2), a manganese ion complex. Alternatively, cerium ammonium nitrate (a cerium ion complex) may also be used.

[0040] When glucose oxidase (GOx) on the anode array 210 of the micro biofuel cell unit 200 catalyzes glucose in body fluids or cerebrospinal fluid, a byproduct—hydrogen peroxide (H2O2)—is naturally produced. In conventional fuel cells, this is considered a hazardous substance, but in this embodiment, it becomes a "chemical trigger" for the next reaction.

[0041] Specifically, due to the addition of manganese doping (Mn) to the precursor medium 700 2+ ) or cerium (Ce 3+ The metal ion complex of GOx, and the hydrogen peroxide byproduct generated by the reaction of the anode array 210 can diffuse to the precursor storage structure 600 at the neural recording electrode array 300. The trace amounts of H2O2 generated by GOx have oxidizing properties, and it acts as a reaction substrate in the local microenvironment, which can oxidize the Mn in the second precursor material in the precursor storage structure 600. 2+ Oxidation into manganese dioxide (MnO2) nanoclusters, or Ce 3+ The MnO2 or CeO2 nanoclusters are transformed into cerium dioxide (CeO2) nanoclusters. These in-situ generated anti-inflammatory nanoclusters of MnO2 or CeO2 are known in the medical field as "nanozymes." After the probe is implanted, the brain's immune cells (microglia) attack the probe, releasing large amounts of reactive oxygen species (ROS) such as superoxide anions and hydroxyl radicals. This is the main cause of glial scarring. The generated anti-inflammatory nanoclusters have extremely strong superoxide dismutase (SOD) and catalase (CAT) mimicry activities, which can continuously catalyze the decomposition of these ROS, further preventing scar formation and thus achieving anti-inflammatory effects.

[0042] In some embodiments, the precursor medium 700 may further include glucose oxidase (GOx) as a catalytic source for generating hydrogen peroxide. By directly adding glucose oxidase (GOx) to the precursor medium 700, hydrogen peroxide can be generated at the electrode sites of the neural recording electrode through the decomposition of glucose by glucose oxidase (GOx), further promoting the generation rate of anti-inflammatory nanoclusters.

[0043] like Figure 1 As shown in the top view, the conductive metal layer 310 is also patterned to form an on-chip microcircuit 400 connecting the neural recording electrode array 300, the anode array 210, and the cathode array 220. The anode array 210 and the cathode array 220 of the micro biofuel cell unit 200 are electrically connected to the neural recording electrode array 300 through this on-chip microcircuit 400, thereby forming a closed-loop driving electric field network.

[0044] The working principle of this device is as follows: like Figure 2 and Figure 3 The diagram shows a cross-sectional view of the self-growing neural electrode before it is implanted in a living organism and a cross-sectional view after it has been implanted in a living organism for a period of time.

[0045] When the device is implanted into brain tissue, glial cell proliferation inevitably occurs due to mechanical mismatch and foreign body reaction at the electrode-tissue interface, resulting in a glial scar layer 900 on the electrode surface. However, over time, glucose and oxygen from the tissue fluid diffuse into the micro-biofuel cell unit 200. Glucose oxidase on the anode catalyzes glucose oxidation to produce electrons, while platinum black on the cathode catalyzes oxygen reduction; the two spontaneously react to generate a driving electric field between the anode and cathode. This driving electric field is applied to the precursor storage structure 600 on the neural recording electrode array 300 via on-chip microcircuit 400, serving as a driving source to continuously electrochemically reduce the first precursor near the electrode interface in the precursor storage structure 600, resulting in the in-situ growth of a conductive nanocluster network 800 on and around the neural recording electrode surface. These nanocluster networks 800 extend outward along the direction of the electric field, actively probing and penetrating the gradually forming glial scar layer 900, thereby reconstructing the electrical connection with neurons.

[0046] Furthermore, both the glucose oxidase in the anode and the precursor medium 700 produce hydrogen peroxide (H2O2) as a byproduct during the catalytic process. The H2O2 in the precursor medium 700 then reacts with the second precursor (Mn... 2+ An oxidation reaction occurs, generating manganese dioxide (MnO2) nanoclusters with superoxide dismutase (SOD) and catalase (CAT) activities in situ. These anti-inflammatory nanoclusters can continuously scavenge reactive oxygen species (ROS) released by activated microglia, chemically inhibiting the amplification of inflammatory signals and thus slowing the excessive proliferation of glial scars.

[0047] Through the dual active mechanisms of physical reconstruction of conductive pathways and modification of the inflammatory environment, this neuroelectrode device achieves dynamic self-repair during long-term implantation, and can maintain stable and high-quality electrophysiological signal recording.

[0048] Example 2: A method for manufacturing a self-generated neural electrode Step 1: Clean the silicon wafer using the RCA standard process, then thermally deposit an aluminum layer with a thickness of 0.3-1 μm on the silicon wafer as a device sacrificial layer. Spin-coat a layer of polyamic acid PAA with a thickness of 5-10 μm on the aluminum-deposited silicon wafer (optionally, prepare parylene-C by chemical vapor deposition, or spin-coat a styrene-isobutylene-styrene SIBS precursor solution). Remove the solvent by stepped annealing (the annealing temperature depends on the solution used, such as 90℃→120℃→250℃→350℃ for polyamic acid), forming a layer of polyimide PI with a thickness of 2-5 μm as a flexible insulating substrate.

[0049] Step 2: Deposit a layer of chromium (Cr / Gold) (or titanium / gold, chromium / platinum, etc.) using magnetron sputtering or electron beam evaporation, with thicknesses of 30 nm and 300 nm respectively. Chromium serves as a transition layer, mainly to increase the adhesion of the noble metal layer.

[0050] Step 3: A photoresist layer with a thickness of 2-5 μm is obtained by spin coating photoresist, pre-baking hardening, exposure, development, and post-baking. Positive photoresist with smaller linewidth and higher precision is preferred.

[0051] Step 4: Use wet etching or dry etching (preferably reactive ion etching) to form a pre-defined anode array, cathode array, neural recording electrode array and on-chip microcircuit on the metal layer. This layer can be collectively referred to as conductive metal layer 310. Then wash away the photoresist with acetone and finally remove the residual photoresist with a plasma stripper.

[0052] Step 5: Repeat spin-coating a 10-15 μm thick layer of polyamic acid (PAA), and then perform step annealing and solvent removal to form a 7-12 μm thick layer of polyimide (PI) as a surface insulating layer.

[0053] Step Six: Similar to Steps Three and Four, the above-mentioned anode array, cathode array, and neural recording electrode array are exposed by photolithography and dry etching to form the nanocluster precursor storage region 600.

[0054] Step 7: Functionalize the exposed micro-biofuel cell unit electrodes using micro-area electrochemical deposition or high-precision microfluidic inkjet printing. Gold nanoparticles (AuNPs) are deposited at the anode array, followed by drop-coating with glucose oxidase (GOx) solution and cross-linking fixation with 1% glutaraldehyde. Finally, a Nafion protective film is applied. The deposited gold nanoparticles increase the specific surface area of ​​the electrodes and, on the other hand, form a synergistic effect with the natural enzyme GOx to enhance catalytic activity. At the cathode array, platinum black catalyst with a "nanoflower" morphology is electrodeposited, or modified with laccase (or alternatively, copper oxidase or bilirubin oxidase).

[0055] Step 8: Using a micro-dispensing manual dispensing system or a micro-dispensing machine, inject the precursor hydrogel layer 700 into the nanocluster precursor storage region 600 prepared in Step 6. This layer includes at least one of the following as conductive nanocluster precursors: a chloroauric acid complex, a platinum salt, or a 3,4-ethylenedioxythiophene (EDOT) monomer; manganese chloride (MnCl2) or cerium ammonium nitrate as an anti-inflammatory nanocluster precursor; hyaluronic acid (HA) or PEG-DA containing a crosslinking agent as a hydrogel prepolymer; and glucose oxidase (GOx) as a hydrogen peroxide generation source. Locally irradiate with ultraviolet light for 10-20 seconds to initially crosslink and anchor the hydrogel, and deposit a 20-100 nm thick layer of Parylene-C on its surface to protect the precursor hydrogel layer 700.

[0056] Step 9: Immerse the entire silicon wafer in dilute hydrochloric acid to release the device from the silicon wafer.

[0057] Step 10: After implantation into the cortex, the micro biofuel cell unit spontaneously starts in the brain tissue fluid (glucose concentration approximately 1-5 mmol / L). A weak open-circuit voltage is generated between the anode and cathode. The on-chip microcircuit applies this micropotential to the neural recording electrode array. The precursor hydrogel layer 700 is slowly electrochemically reduced over 7-14 days, growing outward along the electric field lines. Conductive nanoclusters and anti-inflammatory nanoclusters with particle sizes of 1-50 nm and lengths ranging from several micrometers to tens of micrometers are successfully established, creating a low-impedance signal channel that bridges glial scars and prevents excessive glial cell proliferation. The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A self-generating neural electrode, characterized in that, include: Flexible insulating substrate; A surface insulating layer disposed on the flexible insulating substrate; And a conductive metal layer disposed on the flexible insulating substrate and between the surface insulating layer, the conductive metal layer being patterned to form a neural recording electrode array and a micro biofuel cell unit; The surface insulating layer has windows to expose the electrode sites of the neural recording electrode array and at least a portion of the electrode surface of the micro biofuel cell unit; Among them, a precursor storage structure is provided at the electrode sites of the exposed neural recording electrode array, and the precursor storage structure contains a medium containing a first precursor. The micro biofuel cell unit is configured to generate a microcurrent after implantation into a living organism, and drive the first precursor to undergo an in-situ electrochemical reaction at the interface of the neural recording electrode array to generate conductive nanoclusters.

2. The neural electrode according to claim 1, characterized in that, The anode of the micro biofuel cell unit is modified with glucose oxidase.

3. The neural electrode according to claim 2, characterized in that, The precursor storage structure contains a medium comprising a second precursor, which reacts with hydrogen peroxide to generate anti-inflammatory nanoclusters, which are used to inhibit scar formation.

4. The neural electrode according to claim 3, characterized in that, The second precursor includes manganese ion complexes and / or cerium ion complexes.

5. The neural electrode according to claim 3, characterized in that, The precursor storage structure contains a medium containing glucose oxidase.

6. The neural electrode according to any one of claims 1-5, characterized in that, The first precursor includes at least one of a chloroaurate complex, a platinum salt, or a 3,4-ethylenedioxythiophene (EDOT) monomer.

7. The neural electrode according to any one of claims 1-5, characterized in that, The precursor storage structure is a groove or cavity formed on the surface insulating layer.

8. The neural electrode according to claim 8, characterized in that, The precursor storage structure is also covered by a barrier protective layer, the material of which is Parylene-C.

9. The neural electrode according to any one of claims 1-5, characterized in that, The conductive metal layer also forms an on-chip microcircuit, and the micro biofuel cell unit and the neural recording electrode array are arranged side by side and electrically connected through the on-chip microcircuit.

10. A method for manufacturing a neural electrode as described in any one of claims 1-9, characterized in that, include: A sacrificial layer and a flexible insulating substrate are sequentially formed on the substrate; A conductive metal layer is deposited and patterned on the flexible insulating substrate using photolithography and etching processes to form the electrode patterns and connection traces of the neural recording electrode array and the micro biofuel cell unit. A surface insulating layer is formed covering the conductive metal layer; The electrode sites of the neural recording electrode array and the windows of the micro biofuel cell unit electrodes are exposed using photolithography and etching processes, and a precursor storage structure is formed at the electrode sites of the neural recording electrode array. The electrodes of the micro biofuel cell unit are functionalized. A medium containing a first precursor is introduced into the precursor storage structure; The sacrificial layer is removed to release the device from the substrate.

11. The method for manufacturing a neural electrode according to claim 10, characterized in that, The step of functionalizing the electrodes of the micro biofuel cell unit includes: The anode of the micro biofuel cell unit is modified by immobilizing glucose oxidase, and the cathode of the micro biofuel cell unit is modified by depositing or modifying oxygen reduction catalyst.

12. The method for manufacturing a neural electrode according to claim 10, characterized in that, The step of introducing a medium containing a first precursor into the precursor storage structure includes: The mixed region containing the first precursor, the second precursor, glucose oxidase and hydrogel prepolymer is injected into the storage region and crosslinked by light or heat to solidify it into a hydrogel. A Parylene-C protective layer is vapor-deposited above the precursor storage structure.

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