Dual-response self-supporting monatomic electrode material, preparation method thereof and application of dual-response self-supporting monatomic electrode material in synchronous detection of multi-component small biological molecules
By preparing self-supporting single-atom electrode materials and utilizing the dispersion and coordination environment regulation of Fe single atoms, the problem of simultaneous detection of cysteine and ascorbic acid by traditional electrodes was solved, achieving high-resolution synchronous detection, improving the sensitivity and reliability of detection, and making it suitable for wearable devices and biomedical analysis.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-14
- Publication Date
- 2026-04-14
AI Technical Summary
Existing technologies make it difficult to simultaneously and distinguishably detect cysteine and ascorbic acid at the same electrode interface. The two have similar oxidation potentials and are prone to mutual interference during electrochemical oxidation, making it difficult for traditional electrodes to achieve high-resolution synchronous detection.
Using self-supporting single-atom electrode materials, and through the dispersion and coordination environment regulation of Fe single atoms combined with chelation method, distinguishable dual-response electrochemical detection of cysteine and ascorbic acid can be achieved. The material does not require conductive binders, can be freely cut, and is suitable for wearable electrochemical detection devices.
Clear separation of the oxidation peaks of cysteine and ascorbic acid was achieved, improving the signal-to-noise ratio and sensitivity of the detection. It is suitable for the analysis of multi-component reducing small molecules in complex biological systems and has broad application potential in biomedical analysis and health monitoring.
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Abstract
Description
Technical Field
[0001] This invention relates to a dual-response self-supporting single-atom electrode material, its preparation method, and its application in the simultaneous detection of multi-component biological small molecules, belonging to the field of biodetection technology. Background Technology
[0002] Cysteine and ascorbic acid are small molecules that are widely present in physiological systems and have closely related functions. Cysteine plays a key role in protein synthesis, metal ion balance, and antioxidant defense, while ascorbic acid, as an important biological reducing agent, participates in free radical scavenging and cell protection processes. The concentration changes of both in body fluids are often correlated, reflecting the body's redox balance and are closely related to the occurrence and development of various diseases, such as abnormal liver function, neurodegenerative diseases, cancer, and cardiovascular diseases.
[0003] Therefore, simultaneous detection of cysteine and ascorbic acid in the same detection system not only helps to accurately assess the redox state and metabolic synergies in the body, but also can be used for early disease screening, pharmacological effect assessment, and health status monitoring. Compared with single-molecule detection, simultaneous detection provides richer biochemical information, significantly improving the reliability of analytical diagnosis and its clinical application value.
[0004] However, cysteine and ascorbic acid have similar oxidation potentials and electron transfer kinetics during electrochemical oxidation, and they easily interfere with each other in physiological systems, making it difficult for traditional electrodes to distinguish their oxidation signals. Existing research has mostly focused on achieving selective detection of cysteine in the presence of ascorbic acid, such as the literature "Lee, PT; Lowinsohn, D.; Compton, RG The selective electrochemical detection of homocysteine in the presence of glutathione, cysteine, and ascorbic acid using carbon electrodes. The Analyst 2014, 139 (15), 3755-3762. DOI: 10.1039 / c4an00372a", while reports on high-resolution simultaneous detection of both in a single electrode system are still very few.
[0005] Therefore, there is an urgent need to develop a functional electrode material with dual-response electrochemical activity, which can simultaneously and distinguishably detect multiple small molecules at the same electrode interface, thereby promoting the development and application of multi-component electrochemical sensing technology. Summary of the Invention
[0006] To address the shortcomings of existing technologies, this invention provides a dual-response self-supporting single-atom electrode material, its preparation method, and its application in the simultaneous detection of multi-component small biological molecules. The self-supporting single-atom electrode material of this invention requires no conductive binder, can be freely cut, and is suitable for wearable electrochemical detection devices. Through the dispersion and coordination environment regulation of Fe single atoms, distinguishable dual-response electrochemical detection of cysteine and ascorbic acid is achieved. It can be used for the analysis and detection of multi-component reducing small molecules in complex biological systems, and has broad application potential in biomedical analysis, disease diagnosis, and health monitoring.
[0007] The technical solution of the present invention is as follows:
[0008] A method for preparing a dual-response self-supporting single-atom electrode material includes the following steps:
[0009] The chelating agent, pore-forming agent, binding agent, iron salt, and dispersant are fully dispersed in deionized water, and a supporting material is added. After hydrothermal reaction, washing, drying, and then heat treatment, a dual-response self-supporting single-atom electrode material is obtained.
[0010] According to a preferred embodiment of the present invention, the chelating agent is one or a combination of two or more of glucose, fructose, galactose, mannose or maltose.
[0011] According to a preferred embodiment of the present invention, the pore-forming agent is one or a combination of two or more of zinc gluconate, zinc nitrate hexahydrate, zinc acetate, or zinc sulfate.
[0012] According to a preferred embodiment of the present invention, the combination agent is one of histidine, lysine, or cysteine.
[0013] According to a preferred embodiment of the present invention, the metallic iron salt is one or a combination of two or more of ferric nitrate nonahydrate, ferric chloride, or ferric sulfate.
[0014] According to a preferred embodiment of the present invention, the dispersant is conductive carbon black, preferably EC-600JD, BP2000 or Vulcan XC-72.
[0015] According to the present invention, the preferred mass ratio of chelating agent, pore-forming agent, and binding agent is 1-1.5:0.4-1:0.2-0.5, preferably 1.1:0.5:0.25; the preferred mass ratio of chelating agent to dispersant is 1-1.5:0.03-0.1, preferably 1.1:0.05; the preferred mass ratio of iron salt to chelating agent is 0.05-0.1:1-1.5, preferably 0.07:1.1; and the preferred mass ratio of chelating agent to deionized water is 1-1.5:30-80 g / mL, preferably 1.1:40 g / mL.
[0016] According to the present invention, the preferred conditions for sufficient dispersion are as follows: ultrasonication for 0.5-3 hours.
[0017] According to a preferred embodiment of the present invention, the support material is one or a combination of two or more of carbon paper, carbon cloth, or graphite paper. The amount of support material added to the reactor should ensure that there is no overlap between them to guarantee uniform catalyst growth; the specific amount can be adjusted according to the size of the reactor.
[0018] According to a preferred embodiment of the present invention, the hydrothermal reaction temperature is 120-140°C and the hydrothermal reaction time is 2-5 h.
[0019] According to a preferred embodiment of the present invention, the heat treatment temperature is 800-1000℃, the heat treatment time is 1-3 h, and the heat treatment atmosphere is nitrogen, argon or helium.
[0020] According to the present invention, the synthesized self-supporting single-atom electrode material supports autonomous cutting and can be cut into the required area and pattern.
[0021] A dual-response self-supporting single-atom electrode material is prepared by the above method.
[0022] The above-mentioned dual-response self-supporting single-atom electrode material is used in the simultaneous detection of multi-component biological small molecules.
[0023] According to the present invention, the multi-component biomolecules are preferably cysteine and / or ascorbic acid.
[0024] According to a preferred embodiment of the present invention, the detection method comprises the following steps: differential pulse voltammetry is performed in a three-electrode system, with the working electrode being a self-supporting single-atom electrode material, the reference electrode being Ag / AgCl, and the counter electrode being carbon paper, carbon cloth, carbon rod, Pt wire, or Pt sheet. The working electrode, reference electrode, and counter electrode are immersed in the test sample for testing. Alternatively, the three electrodes can be integrated into a miniature sensing material to achieve miniaturized and integrated detection. Compared to other detection methods, differential pulse voltammetry has a better signal-to-noise ratio and detection sensitivity.
[0025] The technical features and beneficial effects of this invention are as follows:
[0026] 1. Structural innovation: This electrode achieves uniform dispersion of single atoms through chelation and grows directly on the conductive substrate in situ to form a self-supporting structure. It does not require conductive binders, can be freely cut, and is suitable for wearable electrochemical detection devices.
[0027] 2. Highly Sensitive Dual-Response Activity: Through the dispersion of Fe single atoms and the regulation of the coordination environment, it achieves distinguishable dual-response electrochemical signal output for cysteine and ascorbic acid, as well as a stable and highly sensitive electrochemical response. Its mechanism mainly includes:
[0028] ①Single-atom Fe central structure characteristics: The Fe atom exists in the Fe–N4 coordination structure. The unfilled d orbitals endow it with obvious Lewis acid characteristics and local electronic asymmetry, which allows it to have coordination or charge transfer interactions with cysteine thiol and ascorbic acid enediol structures of different strengths.
[0029] ② Atomic-level dispersion effect: Fe active centers are uniformly dispersed on the surface of conductive carbon or oxide support, reducing non-specific adsorption and clustering effects, thereby effectively separating the oxidation peaks of both.
[0030] 3. Excellent detection performance: In differential pulse voltammetry, the oxidation peaks of cysteine and ascorbic acid molecules are clearly separated, achieving high-resolution simultaneous detection.
[0031] 4. The preparation method is simple and scalable: the chelation method has mild conditions and controllable process, and is suitable for the extended preparation of other transition metal single-atom systems.
[0032] 5. Broad application prospects: It can be used for the analysis and detection of multi-component reducing small molecules in complex biological systems, and has broad application potential in fields such as biomedical analysis, disease diagnosis and health monitoring.
[0033] 6. The chelating agent and co-forming agent of this invention form a stable coordination structure with Fe to anchor the Fe active centers, effectively inhibiting the migration and aggregation of metal atoms during heat treatment, thereby achieving single-atom dispersion. The dispersant is used to improve the uniformity of the precursor system, reducing local enrichment in the synthesized precursor. Iron salts are the source of Fe single-atom active centers and are the core of electrocatalytic activity. The ratio of the chelating agent / co-forming agent to the iron salt is controlled in this invention; this ratio is a key factor determining whether Fe can be anchored in a single-atom state. An excessively high iron salt ratio will form nanoclusters. Dispersants and pore-forming agents need to be added to increase the specific surface area and enhance electrode performance. Attached Figure Description
[0034] Figure 1 Transmission electron microscope image of the single-atom electrode material prepared in Example 1;
[0035] Figure 2 Aberration-corrected high-angle annular dark-field scanning transmission electron microscope image of the single-atom electrode material prepared in Example 1;
[0036] Figure 3 The current response diagrams of the two components of the single-atom electrode material prepared in Example 1 were tested simultaneously.
[0037] Figure 4 The single-atom electrode material prepared in Example 1 was subjected to 0 V vs. Ag / AgCl A graph showing the functional relationship between ascorbic acid concentration and current magnitude.
[0038] Figure 5 The single-atom electrode material prepared for Example 1 was subjected to a temperature of 0.42 V. vs. Ag / AgCl A graph showing the functional relationship between cysteine concentration and current magnitude. Detailed Implementation
[0039] To better understand the present invention, specific embodiments are described below.
[0040] Unless otherwise specified, the experimental methods used in the examples are conventional methods.
[0041] Unless otherwise specified, all materials and reagents used in the examples are commercially available.
[0042] Example 1
[0043] A method for preparing a dual-response self-supporting single-atom electrode material includes the following steps:
[0044] 1.1 g of chelating agent fructose, 0.5 g of pore-forming agent zinc nitrate hexahydrate, 0.25 g of binding agent lysine, 70 mg of ferric nitrate nonahydrate, and 50 mg of dispersant EC-600JD were added to 40 mL of deionized water, stirred until homogeneous, and ultrasonically mixed for at least 1 hour to obtain a uniform ink-like consistency. A 1 cm × 2 cm piece of carbon paper was added to the above liquid, and the mixture was transferred to a high-pressure reactor lined with tetrafluoroethylene. The reaction temperature was 130 °C, and the hydrothermal reaction was carried out for 3 hours. After the reaction was completed, the support material was removed and washed at least three times with deionized water. It was then freeze-dried at -50 °C in a freeze dryer. After complete drying, under nitrogen protection, the temperature was raised to 900 °C at a rate of 5 °C / min and held for 2 hours to obtain a self-supporting single-atom electrode material.
[0045] The transmission image of the self-supporting single-atom electrode material prepared in this embodiment is as follows: Figure 1 As shown in the figure, the material exhibits a uniform amorphous carbon-based structure with consistent overall contrast and no obvious metal nanoparticles or clusters, indicating that the iron species are highly dispersed within the carbon framework. (Aberration-corrected transmission image) Figure 2 Several isolated bright spots with slightly higher brightness are visible. These spots are individual Fe sites at the atomic scale, with atomic numbers higher than the surrounding carbon / nitrogen matrix, thus appearing as isolated enhanced spots in Z-contrast imaging. The bright spots are randomly and uniformly distributed within the field of view, indicating that Fe atoms are effectively anchored in the coordination environment of the carbon-based framework. No particulate structures >1 nm were observed in the image, further demonstrating that this synthesis method can suppress iron aggregation and achieve a single-atom dispersed state.
[0046] Example 2
[0047] A method for preparing a dual-response self-supporting single-atom electrode material is as described in Example 1, except that the chelating agent is glucose; other steps and conditions are the same as in Example 1.
[0048] Example 3
[0049] A method for preparing a dual-response self-supporting single-atom electrode material is as described in Example 1, except that the pore-forming agent is zinc gluconate; other steps and conditions are the same as in Example 1.
[0050] Example 4
[0051] A method for preparing a dual-response self-supporting single-atom electrode material is as described in Example 1, except that the coagulant is histidine; other steps and conditions are the same as in Example 1.
[0052] Example 5
[0053] A method for preparing a dual-response self-supporting single-atom electrode material is as described in Example 1, except that the metal iron salt is ferric chloride; other steps and conditions are the same as in Example 1.
[0054] Example 6
[0055] A method for preparing a dual-response self-supporting single-atom electrode material is as described in Example 1, except that the dispersant is BP2000; other steps and conditions are the same as in Example 1.
[0056] Example 7
[0057] A method for preparing a dual-response self-supporting single-atom electrode material includes the following steps: 1 g of chelating agent fructose, 0.4 g of pore-forming agent zinc nitrate hexahydrate, 0.2 g of binding agent lysine, 50 mg of ferric nitrate nonahydrate, and 30 mg of dispersant EC-600JD are added to 30 mL of deionized water, stirred until homogeneous, and ultrasonically mixed for at least 1 h to obtain a uniform ink-like consistency. A 1 cm × 2 cm piece of carbon paper is added to the above liquid, and the mixture is transferred to a high-pressure reactor lined with tetrafluoroethylene. The reaction temperature is 120 °C, and the hydrothermal reaction is carried out for 5 h. After the reaction is complete, the supporting material is removed and washed with deionized water at least 3 times. It is then freeze-dried at -50 °C in a freeze dryer. After complete drying, under nitrogen protection, the temperature is raised to 800 °C at a rate of 5 °C / min and held for 3 h to obtain the self-supporting single-atom electrode material.
[0058] Example 8
[0059] A method for preparing a dual-response self-supporting single-atom electrode material includes the following steps: 1.5 g of chelating agent fructose, 1 g of pore-forming agent zinc nitrate hexahydrate, 0.5 g of binding agent lysine, 100 mg of ferric nitrate nonahydrate, and 100 mg of dispersant EC-600JD are added to 80 mL of deionized water, stirred until homogeneous, and ultrasonically mixed for at least 1 h to obtain a uniform ink-like consistency. A 1 cm × 2 cm piece of carbon paper is added to the above liquid, and the mixture is transferred to a high-pressure reactor lined with tetrafluoroethylene. The reaction temperature is 140 °C, and the hydrothermal reaction is carried out for 2 h. After the reaction is complete, the supporting material is removed and washed at least three times with deionized water. It is then freeze-dried at -50 °C in a freeze dryer. After complete drying, under nitrogen protection, the temperature is raised to 1000 °C at a rate of 5 °C / min and held for 1 h to obtain the self-supporting single-atom electrode material.
[0060] Application Example 1
[0061] Simultaneous detection of multiple components of small biological molecules
[0062] The simultaneous detection of multiple components of small biological molecules was performed using an electrochemical testing method in a three-electrode system. The working electrode was a self-supporting single-atom electrode material prepared by the method in Example 1, the reference electrode was Ag / AgCl, and the counter electrode was carbon paper.
[0063] The test solution was a 0.1 M phosphate buffer solution (pH=7.2) with a pH close to that of sweat, in which a certain amount of cysteine and ascorbic acid were dissolved. The selected testing method was differential pulse voltammetry, with the working electrode, reference electrode, and counter electrode immersed in the test solution. The test voltage was -0.2 V to 0.65 V. vs. Ag / AgCl The potential increment (IncrE) is 0.005 V; the pulse amplitude (Amplitude) is 0.05 V; the pulse width (Pulse Width) is 0.05 seconds; the sampling width (Sampling Width) is 0.0167 seconds; the pulse period (Pulse Period) is 0.5 seconds; and the quiet time (QuietTime) is 2 seconds.
[0064] Test results as follows Figure 3 As shown in the figure, this electrode material exhibits good peak separation characteristics when simultaneously detecting ascorbic acid (AA) and cysteine (Cys). Oxidation peaks of the two components appear near 0 V and 0.42 V, respectively, with clear peak shapes and no obvious overlap, indicating that the electrode interface has good selectivity for different molecules. The relationship between the oxidation peak current and concentration was extracted and fitted. Figure 4 and Figure 5 It can be observed that the current signal exhibits a good linear correlation with the concentration of the target molecule (R0). 2The value >0.98 indicates that the electrode material has excellent sensitivity and reliable quantitative analysis capability in the detection of multi-component small biological molecules.
Claims
1. A method for preparing a dual-response self-supporting single-atom electrode material, characterized in that, Including the following steps: The chelating agent, pore-forming agent, binding agent, iron salt, and dispersant are fully dispersed in deionized water, and a supporting material is added. After hydrothermal reaction, washing, drying, and then heat treatment, a dual-response self-supporting single-atom electrode material is obtained.
2. The method for preparing the dual-response self-supporting single-atom electrode material according to claim 1, characterized in that, The chelating agent is one or a combination of two or more of glucose, fructose, galactose, mannose or maltose.
3. The method for preparing the dual-response self-supporting single-atom electrode material according to claim 1, characterized in that, The pore-forming agent is one or a combination of two or more of zinc gluconate, zinc nitrate hexahydrate, zinc acetate, or zinc sulfate.
4. The method for preparing the dual-response self-supporting single-atom electrode material according to claim 1, characterized in that, The combination agent is one of histidine, lysine, or cysteine.
5. The method for preparing the dual-response self-supporting single-atom electrode material according to claim 1, characterized in that, The metallic iron salt is one or a combination of two or more of the following: ferric nitrate nonahydrate, ferric chloride, or ferric sulfate.
6. The method for preparing the dual-response self-supporting single-atom electrode material according to claim 1, characterized in that, Includes one or more of the following conditions: i. The dispersant is conductive carbon black, preferably EC-600JD, BP2000 or Vulcan XC-72; ii. The mass ratio of chelating agent, pore-forming agent, and binding agent is 1-1.5:0.4-1:0.2-0.5, preferably 1.1:0.5:0.25; the mass ratio of chelating agent to dispersant is 1-1.5:0.03-0.1, preferably 1.1:0.05; the mass ratio of iron salt to chelating agent is 0.05-0.1:1-1.5, preferably 0.07:1.1; the mass ratio of chelating agent to deionized water is 1-1.5:30-80 g / mL, preferably 1.1:40 g / mL; iii. The conditions for sufficient dispersion are as follows: ultrasonic treatment for 0.5-3 hours; iv. The supporting material is one or a combination of two or more of carbon paper, carbon cloth or graphite paper; v. The hydrothermal reaction temperature is 120-140℃, and the hydrothermal reaction time is 2-5 h; vi. The heat treatment temperature is 800-1000℃, the heat treatment time is 1-3 h, and the heat treatment atmosphere is nitrogen, argon or helium.
7. A dual-response self-supporting single-atom electrode material, prepared by the method described in any one of claims 1-6.
8. The application of the dual-response self-supporting single-atom electrode material as described in claim 7 in the simultaneous detection of multi-component biological small molecules.
9. The application according to claim 8, characterized in that, The multi-component biomolecules are cysteine and / or ascorbic acid.
10. The application according to claim 8, characterized in that, The detection method is as follows: Differential pulse voltammetry is used in a three-electrode system. The working electrode is a self-supporting single-atom electrode material, the reference electrode is Ag / AgCl, and the counter electrode is carbon paper, carbon cloth, carbon rod, Pt wire or Pt sheet. The working electrode, reference electrode and counter electrode are immersed in the test sample for testing.