Ion channel protein near-atomic scale confinement dissolution electrochemical machining method based on bionic confinement interface

Abstract

The invention discloses an ion channel protein near-atomic scale confinement dissolution electrochemical machining method based on a bionic confinement interface. The method is characterized in that a bionic phospholipid bilayer mask is spread on a workpiece anode to shield a non-processing area, ion channel protein is embedded into the bionic phospholipid bilayer mask to serve as an electrolyte channel, and when the bionic phospholipid bilayer mask is powered on, the anode dissolution reaction is strictly limited in the ion channel protein channel. Millivolt-level picosecond-nanosecond pulse voltage or current is adopted on the time scale so that anode metal atoms can be removed one by one, electrolytic products are discharged in the modes of electrolyte adjustment, microcosmic acting force, micro vibration and the like so as to ensure sustainable generation of electrochemical reaction, and therefore near-atomic-scale electrolytic machining is achieved. The electrochemical machining technology and the biological field are fused in an interdisciplinary mode, the near-atomic-scale electrochemical dissolution reaction space is constructed, the capacity of electrochemical machining for removing materials in an ion form is approached, and near-atomic-scale electrochemical machining is achieved.

Description

Technical Field

[0001] This invention belongs to the interdisciplinary field of micro-nano manufacturing and electrochemical processing, specifically involving a near-atomic-scale confined dissolution electrochemical processing method for ion channel proteins based on biomimetic confined interfaces. In particular, it relates to a processing technology that utilizes ion channel proteins and phospholipid bilayer masks to construct nanoscale electrolyte channels and achieves near-atomic-scale localized dissolution of metal materials through a precise pulsed electric field, as well as the preparation and application of the corresponding biomimetic interfaces. Background Technology

[0002] As the feature sizes of micro and nano devices continue to approach physical limits, manufacturing technologies face the significant challenge of transitioning from the micrometer scale to the nanometer and even atomic scale. Electrochemical machining technology, due to its stress-free processing characteristics, high material adaptability, and mass production potential, is considered a crucial pathway to overcome the limitations of existing technologies. This technology is based on the principle of anodic ion dissolution, theoretically possessing the potential to remove materials with atomic-level precision using single ions. However, traditional electrochemical machining technology is built upon macroscopic electrochemical principles, and its processing precision is fundamentally constrained by basic physical laws.

[0003] To improve the localization of machining, the research community has developed various micro-electrochemical machining techniques. Ultrashort pulse electrochemical machining (Schuster R, Kirchner V, Allongue P, et al. Electrochemical Micromachining. Science, 2000, 289(5476): 98-101.) significantly improves machining localization by shortening the pulse width to the nanosecond level and utilizing the double-layer charge-discharge characteristics to constrain the reaction time. Jet electrochemical machining uses a micro-electrolyte jet as a tool, improving spatial resolution by controlling the jet morphology. Mask electrochemical machining defines the machining area using a patterned mask. However, these methods still have inherent limitations: further reduction of the pulse width is physically limited by the double-layer charging time; jet stability restricts further improvement in machining accuracy; and the mask preparation process is complex and difficult to achieve three-dimensional nanostructure machining. In-depth analysis shows that although these techniques improve machining performance to some extent, they have all failed to break through the basic framework of "three-dimensional macroscopic electrolyte". Within this framework, two fundamental limitations exist: first, the inherent limitation of the electric field distribution, as the electric field inevitably diverges in a three-dimensional medium according to electrodynamic principles; second, the statistical randomness of the mass transfer process, where the diffusion of ions in the electrolyte leads to blurred processing boundaries. These physical characteristics determine that the precision limit of traditional electrochemical machining is typically on the micrometer scale.

[0004] Existing technologies, such as Chinese inventions CN104551282A, CN111515480A, CN106064261A, and CN113458513A, attempt to further confine the reaction space through a series of measures, including introducing particle assistance and magnetic field enhancement. However, the achievable feature sizes are still limited to a few micrometers to hundreds of nanometers. Fundamentally, electrochemical reactions themselves lack self-limiting characteristics; metal atoms tend to detach from the surface in clusters, making true atomic-level precise localization difficult.

[0005] In recent years, interdisciplinary research has provided new avenues for technological breakthroughs. Patent document CN112719491A first introduced biological concepts into electrochemical machining, using microbial membranes as masks, which inspired innovative directions at the intersection of biotechnology and manufacturing. However, the biofilm used in this technology relies on microbial aggregates, utilizing the gaps between individual microorganisms as electrolyte channels, and its scale remains at the micrometer level. Meanwhile, research on self-assembled masks is relatively limited. For example, dissertations such as "Research on Microtexture Technology of Electrochemical Machining with Hard Particle Masks" proposed using the self-assembly of hard nanoparticles to prepare anodic masks, but the stability and scale effect of these masks remain key issues that need to be addressed.

[0006] In summary, traditional and existing improved electrochemical processing technologies, limited by their physical principles and implementation methods, struggle to achieve processing precision down to the nanometer and atomic scales. Therefore, there is an urgent need to develop a new method that can fundamentally overcome the limitations of the existing framework and confine the electrochemical reaction space to extreme scales. This is precisely the core problem that this invention aims to solve. Summary of the Invention

[0007] Technical Problem Solved: This invention aims to overcome the limitations of traditional electrochemical processing capabilities by providing a near-atomic-scale confined dissolution electrochemical processing method for ion channel proteins based on a biomimetic confined interface. This invention compresses the spatial range of the electrochemical anodic dissolution reaction from the traditional micrometer scale to the nanometer and even sub-nanometer scale, thereby fully leveraging the theoretical potential of electrochemical processing to remove materials step-by-step in ionic form. This provides a highly localized, stress-free, and widely adaptable processing method for the fabrication of three-dimensional nanostructures and atomic-scale devices.

[0008] Technical solution: A biomimetic confined interface for near-atomic scale electrochemical machining, comprising: a phospholipid bilayer insulating mask supported on the anode surface of a workpiece; and an ion channel protein embedded in the phospholipid bilayer insulating mask; wherein the ion channel protein forms a unique electrolyte channel at the nanoscale or near-atomic scale in the phospholipid bilayer insulating mask.

[0009] The above-mentioned method for preparing the biomimetic confined interface includes the following steps: (a) pretreating the atomically flat anode surface of the workpiece to make its surface roughness Ra≤0.5 nm and forming a hydrophilic surface modification layer; (b) forming a dense phospholipid bilayer insulating mask on the pretreated anode surface of the workpiece through the self-assembly of phospholipid monomers in the electrolyte; (c) embedding ion channel proteins or their functional analogs into the phospholipid bilayer insulating mask through hydrophobic interactions, so that the transmembrane pores of the ion channel proteins penetrate the mask to form the unique electrolyte channel.

[0010] In step (a), the pretreatment includes degreasing, washing, drying, and plasma treatment; the surface modification layer is a hydrophilic layer formed by plasma treatment.

[0011] In step (b), the raw materials used for the self-assembly are selected from at least one of dioleoylphosphatidylcholine, natural phospholipids, synthetic phospholipids, or block copolymers.

[0012] In step (c), the ion channel protein is an α-hemolysin ion channel protein, whose transmembrane hydrophobic region structure matches the thickness of the hydrophobic region of the phospholipid bilayer insulating mask, and the inner diameter of the unique electrolyte channel is approximately 1.4 nm.

[0013] Following step (c), the process further includes a step of performing a stability enhancement treatment on the phospholipid bilayer insulating mask, wherein the stability enhancement treatment is a UV-induced crosslinking treatment.

[0014] The inner walls of the aforementioned ion channel proteins have tunable charge properties, enabling them to exhibit preset stable charge properties under the pH conditions of the processing electrolyte, thereby optimizing the transport selectivity of specific reactive ions.

[0015] A near-atomic-scale confined dissolution electrochemical machining method for ion channel proteins based on a biomimetic confined interface includes the following steps: (i) placing a workpiece with the biomimetic confined interface as the anode in an electrolyte; (ii) applying a pulsed electric field between the anode and the tool cathode, wherein the pulse width of the pulsed electric field is on the order of picoseconds to nanoseconds and the amplitude is on the order of millivolts; (iii) the pulsed electric field drives the reactive ions in the electrolyte to be directionally transported through the unique electrolyte channel of the ion channel protein to a very small micro-region on the anode surface of the workpiece, thereby initiating the electrochemical dissolution and removal of metal atoms in the micro-region.

[0016] In step (ii), the pulse width of the pulsed electric field is 100 ps to 500 ps, ​​the pulse interval is 200 ps to 1 ns, and the amplitude is 10 mV to 100 mV.

[0017] In step (i), the electrolyte is a static 0.1 M NaCl solution; in step (iii), the shape and depth of the nanostructure are controllably processed by controlling the number of times and parameters of the pulsed electric field.

[0018] Technical Principle: This invention achieves near-atomic-scale spatial confinement and stepwise material removal of electrochemical reactions by constructing a biomimetic confined interface and synergistically utilizing pulsed electric field control. The foundation lies in the self-assembly of a dense phospholipid bilayer insulating mask on the anode surface of the workpiece, embedding an ion channel protein with an inner diameter at the nanometer scale. The transmembrane pores of this protein become the sole channel for electrolyte ions to reach the workpiece surface, thus physically compressing the reaction space to a near-atomic-scale region comparable to the pore size. Within this confined space, a precisely designed ultrashort pulsed electric field with millivolt, picosecond to nanosecond pulse widths is applied. This electric field force drives specific reaction ions in the electrolyte to pass directionally and at high speed through the bio-nanochannel, concentrating their effect on a very small region directly below the channel. The tunable chemical properties of the inner wall of the bio-ion channel allow for selective optimization of ion transport, while the duration of the ultrashort pulse matches the local charging process of the double layer within the nano-confined space, ensuring that each pulse cycle drives only a limited number of surface metal atoms to undergo electrochemical dissolution. The pulse interval provides the necessary time for the diffusion and removal of reaction products. The synergistic effect of spatial confinement structure, directional transport and sieving of ions, and stepwise pulse control transforms the traditional macroscopic electrochemical dissolution process into a highly controllable deterministic removal process at the near-atomic scale, thereby breaking through the precision limits of traditional electrochemical processing.

[0019] Beneficial Effects: This invention constructs a physically isolated reaction interface that retains only atomic-scale channels by combining a biomimetic phospholipid bilayer insulating mask with ion channel proteins possessing specific nanopores. This structure fundamentally confines electrolyte transport and electrochemical reactions within the nanometer or even sub-nanometer range defined by the inner diameter of the protein channels, thereby breaking through the micrometer-level precision limit imposed by electric field divergence and ion diffusion in traditional electrochemical processing. This provides a new physical basis for achieving near-physically limited localized material removal. This biomimetic confined interface combines the excellent insulation and dynamic adaptability of the phospholipid bilayer with the efficient ion transport and molecular selectivity of biological ion channels. The phospholipid bilayer, with its molecular-level thickness and extremely high intrinsic resistance, achieves electrical insulation shielding of non-processed areas, while its inherent self-sealing and dynamic fluidity provide an ideal flexible environment for the stable embedding and functional maintenance of ion channel proteins. This synergy of structural stability and dynamic adaptability ensures the durability and reliability of the processing under extreme spatial constraints. Benefiting from the inherent characteristics of biological ion channels as highly efficient ion transport molecular machines, this method possesses high-throughput, low-impedance ion transport capabilities, effectively alleviating the problem of easy clogging in traditional nanochannels. Furthermore, through rational chemical modification of the channel inner wall, the preferential transport of specific reactive ions can be actively regulated, and the retention and adsorption of byproducts within the channel can be suppressed, achieving a synergistic improvement in transport efficiency and selectivity, thereby ensuring the consistency and stability of the processing. At the process implementation level, this invention abandons the absolute dependence on ultra-precision motion control systems or complex photolithography equipment, instead utilizing the highly parallel and relatively simple strategy of molecular self-assembly to construct atomic-scale processing stations. This significantly reduces the technical threshold and equipment cost for achieving near-atomic-scale precision manufacturing. Most importantly, based on the high parallelism of self-assembly, a massive number of functional ion channels can be integrated on the workpiece surface at once, with each channel serving as an independent processing unit. Through synchronous control of the global electric field, parallel manufacturing of large-area, highly consistent nanostructure arrays can be achieved, fundamentally solving the core bottleneck of low efficiency in single-point scanning processing and providing a highly promising solution for the large-scale fabrication of future nanodevices. The entire processing is carried out in a mild solution environment at room temperature and pressure, which essentially avoids the extreme physical fields of high energy consumption and embodies the advanced manufacturing concept of green and sustainable development. This method deeply integrates electrochemical processing technology with biology and nanotechnology, representing a paradigm shift from macroscopic, highly interventionist manufacturing to microscopic, soft matter control. Attached Figure Description

[0020] Figure 1 This is a schematic diagram showing the distribution of the phospholipid bilayer insulating mask and ion channel proteins on the workpiece anode.

[0021] Figure 2This is a schematic diagram of a near-atomic-scale confined dissolution electrolytic processing method for ion channel proteins.

[0022] Figure 3 This is a schematic diagram illustrating the self-assembly principle of phospholipid monomers.

[0023] Figure 4 This is a schematic diagram of the structure of an ion channel protein.

[0024] Figure 5 This is a schematic diagram of the interaction between a phospholipid bilayer insulating mask and ion channel proteins.

[0025] Figure 6 This is a schematic diagram of the formation of a confined space.

[0026] Figure 7 This is a high-resolution TEM image of a 1nm nickel nanopore obtained through electrolytic processing.

[0027] Figure 8 It is an AFM image showing incomplete coverage of a phospholipid bilayer insulating mask on a rough workpiece surface.

[0028] Figure 9 This is a high-resolution TEM image of a nanopore processed under conditions where the phospholipid bilayer insulating mask is not fully spread.

[0029] Figure 10 This is a comparison chart of breakdown voltage before and after UV crosslinking.

[0030] Figure 11 It is an AFM image of the surface roughness of the anode of an atomically flat workpiece.

[0031] Figure 12 This is a comparison of the hydrophobic angles of the anode surface of the workpiece before and after plasma hydrophilic treatment.

[0032] Figure 13 This is a negatively stained electron microscope image of α-hemolysin ion channel protein.

[0033] Labels and names in the figure: 1. Electrolytic cell; 2. Tool cathode; 3. Electrolyte; 4. Pulse power supply; 5. Phospholipid bilayer; 5-1. Phospholipid monomer; 5-2. Hydrophilic head; 5-3. Hydrophobic tail; 5-4. Hydrophobic interaction; 5-5. Self-assembly; 5-6. Hydrophobic region; 6. Ion channel protein; 6-1. Upper interface of ion channel protein; 6-2. Electrolyte inlet; 6-3. Lower interface of ion channel protein; 6-4. Electrochemical reaction region; 6-5. Electrolyte channel; 6-6. Transmembrane region; 6-7. Hydrophobic interaction I; 7. Modification layer; 8. Workpiece anode; 9. Confined space. Detailed Implementation

[0034] The specific implementation process of the present invention will be described in detail below with reference to the accompanying drawings.

[0035] A near-atomic-scale confined dissolution electrochemical machining method for ion channel proteins is disclosed. The core idea of ​​this method is to construct an insulating biomimetic membrane (phospholipid bilayer) on the anode surface of the workpiece using self-assembly technology, and precisely embed ion channel proteins with specific ion selectivity and nanopores into this membrane. This protein channel becomes the sole pathway for electrolyte ions to reach the workpiece surface. By applying a precisely controllable pulsed electric field, ions are driven to undergo directional transport through this nanochannel, thereby initiating an electrochemical dissolution reaction of the metal only in a tiny region directly below the channel (with a scale comparable to the channel's inner diameter), achieving near-atomic-scale material removal.

[0036] The technical solution of this method mainly includes the following steps:

[0037] (I) Construction of a biomimetic confined interface:

[0038] (1.1) First, the anode surface of the workpiece is pretreated to obtain a flat surface suitable for supporting the biomimetic membrane.

[0039] (1.2) Subsequently, a dense phospholipid bilayer insulating mask is formed on the surface of the workpiece through self-assembly. This mask serves as insulation and spatial barrier on a macroscopic level.

[0040] (1.3) Ion channel proteins or their functional analogs are functionally embedded into the above-mentioned phospholipid bilayer using a directed self-assembly technique. The transmembrane pores of the protein penetrate the insulating mask, forming a unique electrolyte channel with a size at the nanometer or near-atomic scale between the workpiece surface and the external electrolyte.

[0041] (ii) Confined electrochemical dissolution processing:

[0042] (2.1) The workpiece with the constructed biomimetic interface is placed in the electrolyte as the anode.

[0043] (2.2) A precision pulsed electric field is applied between the workpiece anode and the tool cathode. The parameters of the electric field (such as pulse width, interval, and amplitude) are designed to precisely control the charging and discharging process of the double layer.

[0044] (2.3) Under the action of a pulsed electric field, the reactive ions (such as OH⁻, Cl⁻, etc.) in the electrolyte are selectively driven through the nanopores of ion channel proteins and transported at high speed and directionally to the tiny confined area on the surface of the workpiece.

[0045] (2.4) Ions undergo instantaneous, localized electrochemical reactions with metal atoms on the workpiece surface at the channel exit, resulting in the dissolution of individual or small clusters of metal atoms. The reaction products are discharged from the same channel or auxiliary channel through diffusion or electromigration.

[0046] (2.5) By controlling the number of times and parameters of pulsed electric field application, controllable fabrication of complex nanostructures can be achieved.

[0047] (III) Stability and Regulation Strategies:

[0048] (3.1) Enhanced interface stability: The mechanical strength and chemical stability of the phospholipid bilayer insulating mask can be enhanced by polymerization, cross-linking and other means.

[0049] (3.2) Channel function regulation: Ion transport selectivity and product expulsion capacity can be optimized by modifying the inner wall chemical properties of ion channel proteins (such as charge and hydrophilicity / hydrophobicity).

[0050] (3.3) Interface bonding optimization: An intermediate modification layer can be introduced between the workpiece surface and the biomimetic film to improve the overall interface strength.

[0051] (3.4) Suppression of environmental disturbances: By controlling the fluid state of the electrolyte (e.g., by using static or extremely low flow rate), the influence of fluid shear force on the fragile biomimetic interface is reduced.

[0052] A biomimetic confined interface for the above-described method, which is the core component of this invention, is described as follows: The interface is a composite thin film structure supported on the anode surface of a workpiece, comprising: an optional intermediate modification layer for enhancing the adhesion between the substrate and the upper thin film; a phospholipid bilayer insulating mask serving as the main insulating barrier layer; and an ion channel protein embedded in the phospholipid bilayer in a transmembrane manner, the internal pores of which constitute nanoscale ion transport channels connecting the substrate and the external environment, and the chemical properties of the channel inner walls can be designed and controlled according to processing requirements.

[0053] Example 1

[0054] like Figure 2 As shown, the electrolytic machining apparatus of the present invention mainly consists of an electrolytic cell 1; a tool cathode 2; an electrolyte 3; a power supply 4; a phospholipid bilayer 5; phospholipid monomers 5-1; ion channel proteins 6; a modification layer 7; and a workpiece anode 8. The electrolyte 3 is injected into the electrolytic cell 1, and the tool cathode 2 and workpiece anode 8 are immersed in the electrolyte 3 and electrically connected to the power supply 4. The surface of the workpiece anode 8 is successively covered by the modification layer 7 and the phospholipid bilayer 5. The phospholipid bilayer 5 is composed of phospholipid monomers 5-1, and the ion channel protein 6 is embedded within the phospholipid bilayer 5 and connected to the workpiece anode 8.

[0055] like Figure 3As shown, the phospholipid monomer self-assembly process of the present invention mainly consists of phospholipid monomer 5-1; hydrophilic head 5-2; and hydrophobic tail 5-3. Two phospholipid monomers 5-1 are connected by hydrophobic interaction 5-4, and then by self-assembly 5-5, several phospholipid monomers 5-1 form a phospholipid bilayer 5, and a hydrophobic region 5-6 is formed in the region where the hydrophobic tails 5-3 are connected.

[0056] like Figure 4 As shown, the structure of the ion channel protein 6 implementing the present invention is as follows: an upper ion channel protein interface 6-1 at the top of the protein and a lower ion channel protein interface 6-3 at the bottom of the protein; the center of the upper ion channel protein interface 6-1 is an electrolyte inlet 6-2; the electrolyte channel 6-5 below the electrolyte inlet 6-2 runs through the entire ion channel protein 6 and is connected to the workpiece anode 8, wherein the region connected to the workpiece anode 8 is the electrochemical reaction region 6-4, and the part of the ion channel protein 6 embedded in the phospholipid bilayer 5 is the transmembrane region 6-6.

[0057] like Figure 5 As shown, the interaction between the phospholipid bilayer and ion channel protein in implementing the present invention is mainly in the hydrophobic region 5-6; the transmembrane region 6-6; and the hydrophobic interaction I 6-7.

[0058] like Figure 6 As shown, the confined space 9 in which the present invention is implemented is mainly composed of ion channel protein 6, phospholipid bilayer and workpiece anode 8.

[0059] The following four steps are required to achieve near-atomic scale electrolytic processing using this invention:

[0060] Workpiece pretreatment steps: Select pure nickel workpiece 8, first perform degreasing, water washing, and drying, then perform plasma treatment with argon-hydrogen mixed gas (volume ratio 96:4) to form a hydrophilic modification layer 7 on the surface to enhance the bonding force of the phospholipid bilayer. Implementation difficulty: If the surface roughness (Ra) of the workpiece is greater than 1 nm, it may lead to incomplete coverage of the phospholipid bilayer (e.g., ...). Figure 8 As shown in the figure, leakage points are generated. Atomic force microscopy (AFM) is used to check the surface flatness to ensure Ra ≤ 0.5 nm; substandard workpieces are subjected to mechanical-chemical polishing treatment.

[0061] Construction of a biomimetic confined interface: Dioleoylphosphatidylcholine (DOPC) phospholipid monomer (concentration 10 mg / mL) was dissolved in phosphate buffer (electrolyte) at pH 7.4. The workpiece was immersed in the electrolyte for 5-10 minutes, and a phospholipid bilayer insulating mask was formed on the workpiece surface through self-assembly. Subsequently, 1 μg / mL α-hemolysin ion channel protein (inner diameter approximately 1.4 nm) was added and embedded into the mask using hydrophobic interactions. Challenges: Identification of the characteristic electrical signals formed by the biomimetic confined interface and testing the breakdown voltage of the phospholipid bilayer insulating mask. Solution: Before adding the α-hemolysin ion channel protein, the change in current under constant voltage was tested. If the current is infinitely close to 0 pA, the phospholipid bilayer insulating mask is well formed, and the next step can be performed. Simultaneously, the phospholipid bilayer insulating mask was subjected to UV-induced cross-linking treatment (irradiation with a 254 nm UV lamp for 15 minutes) to enhance stability and breakdown voltage.

[0062] Electrolytic machining process: The workpiece is placed as the anode in a static electrolyte (0.1 M NaCl solution), and the tool cathode is a platinum needle tip (10 μm spacing). A pulsed electric field is applied (parameters: pulse width 200 ps, ​​interval 500 ps, ​​amplitude 50 mV) to drive cations and anions through protein channels. Figure 2 and Figure 6 Implementation challenges: Inappropriate pulse parameters can easily lead to over-etching or insufficient reaction during machining. Appropriate pulse parameters can ensure the quality of the machined hole diameter. Figure 7 ).

[0063] Comparative Example 1: Maintaining the same processing parameters and steps as in Example 1, but modifying the workpiece anode surface roughness to be higher than 1 nm, will result in incomplete coverage of the phospholipid bilayer insulating mask. Figure 8 This results in severe leakage, and under these circumstances, the pore shape processed is no longer similar to that of the α-hemolysin ion channel protein. Figure 9 ), exhibiting many irregularly shaped dissolution characteristics.

[0064] Comparative Example 2: The same processing parameters and steps as in Example 1 were used to perform UV-induced crosslinking treatment on the phospholipid bilayer insulating mask. Leakage current was detected in the phospholipid bilayer insulating mask without UV crosslinking treatment at approximately 950 ms. Figure 10 The phospholipid bilayer insulating mask that has undergone ultraviolet cross-linking still maintains a high current shielding effect, indicating that this method can significantly improve the stability and breakdown voltage of the phospholipid bilayer insulating mask.

[0065] Example 2

[0066] This embodiment systematically studies the crucial role of the hydrophilic layer on the workpiece surface in the formation of the phospholipid bilayer insulating mask, verifying the necessity of hydrophilic treatment in near-atomic scale electrolytic machining. The specific process includes: preparing two groups of pure nickel workpieces with different surface hydrophobic angles (…). Figure 12 The hydrophilic group had a hydrophobic angle of 4°±2°, and the moderately hydrophilic group had a hydrophobic angle of 50°±5°. The hydrophilic group underwent the same plasma treatment as in Example 1, while the moderately hydrophilic group only underwent simple cleaning, degreasing, and drying. A phospholipid bilayer insulating mask was constructed by self-assembly on an atomically flat surface and an unmodified α-hemolysin ion channel protein was embedded within it. Figure 13 The integrity of the mask was evaluated by testing the CV curves and breakdown voltage using cyclic voltammetry. The results showed that the CV curve of the hydrophilic surface was a flat, linear curve (current density <1 nA / cm²). 2 The hydrophilic surface showed uniform mask coverage, while the CV curve of the hydrophobic surface showed significant redox peaks, indicating severe mask failure. This comparison clearly reveals that the hydrophilic layer on the workpiece surface, by reducing the hydrophobic angle (which needs to be less than 10°), can effectively promote the dense self-assembly of phospholipid monomers, forming a high-performance insulating mask, thus providing a prerequisite for the confined dissolution processing of ion channel proteins.

Claims

1. A biomimetic confined interface for near-atomic scale electrochemical processing, characterized in that, include: A phospholipid bilayer insulating mask supported on the anode surface of the workpiece; And ion channel proteins embedded in the phospholipid bilayer insulating mask; wherein the ion channel proteins form unique electrolyte channels at the nanoscale or near-atomic scale in the phospholipid bilayer insulating mask.

2. A method for preparing the biomimetic confined interface as described in claim 1, characterized in that, Includes the following steps: (a) Pre-treating the atomically flat anode surface of the workpiece and forming a hydrophilic surface modification layer; (b) Forming a dense phospholipid bilayer insulating mask on the pre-treated anode surface of the workpiece through the self-assembly of phospholipid monomers in the electrolyte; (c) Embedding an ion channel protein or its functional analogue into the phospholipid bilayer insulating mask through hydrophobic interactions, so that the transmembrane pores of the ion channel protein penetrate the mask to form the unique electrolyte channel.

3. The method according to claim 2, characterized in that, In step (a), the pretreatment includes degreasing, washing, drying, and plasma treatment; the surface modification layer is a hydrophilic layer formed by plasma treatment.

4. The method according to claim 2, characterized in that, In step (b), the raw materials used for self-assembly are selected from at least one of dioleoylphosphatidylcholine, natural phospholipids, synthetic phospholipids, or block copolymers.

5. The method according to claim 2, characterized in that, In step (c), the ion channel protein structure allows selective passage of electrolyte ions and smooth discharge of electrolyte products, and its transmembrane hydrophobic region structure matches the hydrophobic region thickness of the phospholipid bilayer insulating mask.

6. The method according to claim 2, characterized in that, Following step (c), the process further includes a step of performing a stability enhancement treatment on the phospholipid bilayer insulating mask, wherein the stability enhancement treatment is a polymerization, crosslinking, or a combination thereof.

7. The method according to claim 2, characterized in that, The ion channel protein has tunable charge properties on its inner wall, enabling it to exhibit a preset stable charge property under the pH conditions of the processing electrolyte, thereby optimizing the transport selectivity of specific reactive ions.

8. A method for near-atomic-scale confined dissolution and electrolytic processing of ion channel proteins based on the biomimetic confined interface described in claim 1, characterized in that, The method includes the following steps: (i) placing a workpiece with the biomimetic confined interface as an anode in an electrolyte; (ii) applying a pulsed electric field between the anode and the tool cathode, wherein the pulse width of the pulsed electric field is on the order of picoseconds to nanoseconds and the amplitude is on the order of millivolts; (iii) the pulsed electric field drives the reactive ions in the electrolyte to be directionally transported through the unique electrolyte channel of the ion channel protein to a very small micro-region on the surface of the workpiece anode, thereby triggering the electrochemical dissolution and removal of metal atoms in the micro-region.

9. The method according to claim 8, characterized in that, In step (iii), the shape and depth of the nanostructure are controlled by controlling the number of times and parameters of the pulsed electric field applied.

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