Nickel-based composite nano enzyme as well as preparation method and application thereof
Synthesis of nickel-based composite nanoenzymes by electrochemical deposition method in microfluidic electrochemical system has solved the problems of high synthesis conditions, long time and uneven modification in the prior art, and achieved efficient and low-cost nickel-based composite nanoenzyme synthesis, which is suitable for the application of a variety of electrochemical sensors.
Patent Information
- Application Number
- CN202510298803.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-13
- Publication Date
- 2025-06-13
AI Technical Summary
The synthesis conditions of existing nickel-based composite nanoenzymes are high, time-consuming, and uneven modifications. Traditional electrochemical synthesis methods require a large amount of electrolyte solutions, resulting in high costs and difficulty in handling waste liquids.
A microfluidic electrochemical system is used to build a device, and nickel-based composite nanoenzymes are synthesized on the surface of the working electrode through electrochemical deposition. The nickel-based nanomaterial and conductive polymer electrolyte are used for electrodeposition to form a nickel-based composite nanoenzyme with a large specific surface area.
It realizes efficient synthesis of nickel-based composite nanoenzymes, has good electron transfer performance and excellent electrocatalytic performance, reduces synthesis cost and energy consumption, simplifies the equipment structure, and is suitable for electrochemical sensors of neurotransmitters, glucose and ascorbic acid.
Smart Images
Figure CN120138434A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of electrochemical synthesis and analysis, and particularly relates to a nickel-based composite nanozyme and a preparation method and application thereof. Background Art
[0002] Compared with small molecule detection methods such as colorimetry, surface-enhanced Raman scattering method, and fluorescence analysis method, the electrochemical detection method has the advantages of easy integration, fast detection speed, and low cost, which makes electrochemical detection more suitable for continuous monitoring. The detection performance of an electrochemical sensing device depends on the electron transfer performance and electrocatalytic performance of the sensitive element.
[0003] Currently, sensors with Ni 3 (HHTP) 2 -based composite nanozymes as sensitive elements are mainly prepared by chemically synthesizing nickel-based composite nanozymes and then drop-coating them on the working electrode, which has the disadvantages of high synthesis conditions, long time consumption, and uneven modification. Compared with the chemical synthesis method, the electrodeposition method can simply control the synthesis rate, the uniformity and sensing performance of nickel-based composite nanozymes by changing the composition and concentration of the electrolyte solution and the type and magnitude of the electrical signal. In addition, since the electrodeposition process does not require a high-temperature and high-pressure environment, its energy consumption is significantly reduced, and it is more green and safe. However, traditional electrochemical synthesis and detection methods still require a large amount of electrolyte solution, which will increase the cost and the difficulty of waste liquid treatment. Therefore, the in-situ synthesis of sensitive elements and the sensing of analytes using a microfluidic electrochemical system can improve the integration degree of the system and reduce the synthesis and detection costs.
[0004] Therefore, it is necessary to develop a nickel-based composite nanozyme that has a large specific surface area, good electron transfer performance, and excellent electrocatalytic performance. Summary of the Invention
[0005] The purpose of the present invention is to provide a nickel-based composite nanozyme that has a large specific surface area, good electron transfer performance, and excellent electrocatalytic performance in view of the deficiencies of the prior art.
[0006] To achieve the above purpose, the present invention adopts the following technical solutions:
[0007] A preparation method of a nickel-based composite nanozyme, comprising the following steps:
[0008] Step S1, device assembly: Lay the PDMS membrane with a microchannel flat on a glass slide, place the working area of the working electrode downward in the microchannel of the PDMS membrane, buckle the PDMS gland on the PDMS microchannel membrane, and make the working electrode embedded in the gland. Assemble the reference electrode and the counter electrode, and then insert the inlet tube and the outlet tube to form a microfluidic electrochemical device;
[0009] Step S2, Electrochemical Deposition: Inject the electrolyte containing nickel-based nanomaterials and conductive polymers into the microfluidic electrochemical device. After the electrodeposition reaction, the nickel-based composite nanozyme is formed on the surface of the working electrode.
[0010] Preferably, in step S1, the working electrode is selected from at least one of indium tin oxide glass, gold electrode, and glassy carbon electrode.
[0011] Preferably, in step S2, the nickel-based nanomaterials are selected from Ni 3 (HHTP) 2 。
[0012] Preferably, in step S2, the conductive polymers are selected from at least one of polypyrrole, polyaniline, and poly(3,4-ethylenedioxythiophene).
[0013] Preferably, in step S2, the volume of the electrolyte is 100 - 200 μL.
[0014] Preferably, in step S2, the concentration of nickel-based nanomaterials in the electrolyte is 0.25 - 1 mg / mL, and the concentration of conductive polymers is 10 - 200 mM.
[0015] Preferably, in step S2, the potential during the deposition reaction is 0.7 - 0.9 V, and the time is 40 - 300 s.
[0016] In addition, the present invention also provides a nickel-based composite nanozyme prepared by the above method.
[0017] In addition, the present invention also provides an application of the above nickel-based composite nanozyme, and the nickel-based composite nanozyme is used for neurotransmitters, glucose, and ascorbic acid in an electrochemical sensor.
[0018] Preferably, the application of a nickel-based composite nanozyme in an electrochemical sensor includes the following steps:
[0019] Step S1, Introduce a buffer solution and a test solution into the microfluidic electrochemical device;
[0020] Step S2, Obtain the sensitivity and detection limit of the sensor according to the current response generated by the nickel-based composite nanozyme on the working electrode;
[0021] Among them, the buffer solution is selected from phosphate buffer solution.
[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0023] 1) The present invention provides a method for preparing a nickel-based composite nanozyme. By constructing a microfluidic-electrochemical system and synthesizing a novel nickel-based composite nanozyme on the electrode surface through copolymerization in the micro-system, it is used for the detection of neurotransmitters, glucose, and ascorbic acid in electrochemical sensors.
[0024] 2) The nickel-based composite nanozyme prepared by the present invention has a large specific surface area, good electron transfer performance and excellent electrocatalytic performance. The microfluidic electrochemical sensor constructed with the working electrode modified by it as the sensitive element has the advantages of simple detection equipment, small sample demand, and easy portability compared with other traditional sensing methods, and has good application value and development prospects in the early screening of diseases, home health monitoring and drug research and development. Brief Description of the Drawings
[0025] Figure 1 It is a flowchart for constructing a microfluidic electrochemical device.
[0026] Figure 2 It is the nickel-based composite nanozyme Ppy-Ni 3 (HHTP) 2 Characterization diagram of scanning electron microscope SEM.
[0027] Figure 3 It is the nickel-based composite nanozyme Ppy-Ni prepared by the present invention 3 (HHTP) 2 Characterization diagram of atomic force microscope AFM.
[0028] Figure 4 It is the nickel-based composite nanozyme Ppy-Ni prepared by the present invention 3 (HHTP) 2 X-ray photoelectron spectroscopy XPS characterization diagram.
[0029] Figure 5 It is the sensitivity and detection limit of the nickel-based composite nanozyme prepared in Example 1 as a sensor in a microfluidic electrochemical device.
[0030] Among them, 1 - glass slide; 2 - PDMS microchannel; 3 - working electrode; 4 - flow channel tube; 5 - reference electrode; 6 - counter electrode; 7 - PDMS gland. Detailed Embodiments
[0031] To make the technical solutions and advantages of the present invention clearer, the following will combine specific embodiments to clearly and completely describe the technical solutions of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.
[0032] According to the first aspect of the present application, the present application provides a method for preparing a nickel-based composite nanozyme, comprising the following steps:
[0033] Step S1, device assembly: lay the PDMS membrane with microchannels flat on the glass slide, place the working area of the working electrode downward in the microchannels of the PDMS membrane, buckle the PDMS gland on the PDMS microchannel membrane, and embed the working electrode in the gland. Assemble the reference electrode and the counter electrode, and then insert the liquid inlet tube and the liquid outlet tube to form a microfluidic electrochemical device;
[0034] Step S2, electrochemical deposition: inject the electrolyte containing nickel-based nanomaterials and conductive polymers into the microfluidic electrochemical device, and after the electrodeposition reaction, form the nickel-based composite nanozyme on the surface of the working electrode.
[0035] Among them, to prepare the nickel-based composite nanozyme, the present invention first constructs a microfluidic electrochemical device, which is composed of a glass slide, a PDMS microchannel, a working electrode, a PDMS gland, a reference electrode, a counter electrode, a liquid inlet tube, a liquid outlet tube and a fixture. Then, use this device for one-step in-situ electrodeposition synthesis of nickel-based composite nanozymes.
[0036] In some embodiments, the prepared nickel-based composite nanozyme is Ppy-Ni 3 (HHTP) 2 。
[0037] In some embodiments, in step S1, the working electrode is selected from at least one of indium tin oxide glass, gold electrode and glassy carbon electrode.
[0038] In some embodiments, in step S2, the nickel-based nanomaterials are selected from Ni 3 (HHTP) 2 。
[0039] In some embodiments, in step S2, the conductive polymers are selected from at least one of polypyrrole, polyaniline and poly(3,4-ethylenedioxythiophene).
[0040] In some embodiments, in step S2, the concentration of nickel-based nanomaterials in the electrolyte is 0.25-1 mg / mL, for example, it can be 0.25 mg / mL, 0.45 mg / mL, 0.5 mg / mL, 0.65 mg / mL, 0.75 mg / mL, 0.85 mg / mL, 0.95 mg / mL or 1 mg / mL, and the concentration of conductive polymers is 10-200 mM, for example, it can be 10 mM, 20 mM, 50 mM, 100 mM, 150 mM or 200 mM.
[0041] Among them, when the concentration of the nickel-based nanomaterial is less than this range, it will lead to insufficient conductivity of the solution and unable to perform electrodeposition. When the concentration of the nickel-based nanomaterial is greater than this range, it will lead to too intense deposition reaction and uneven deposition. When the concentration of the conductive polymer is less than this range, it will lead to difficulty in monomer polymerization and unable to form a film. When the concentration of the conductive polymer is greater than this range, it will lead to too intense deposition reaction and uneven deposition.
[0042] In some embodiments, in step S2, the volume of the electrolyte is 100 - 200 μL, for example, it can be 100 μL, 120 μL, 140 μL, 160 μL, 180 μL or 200 μL.
[0043] In some embodiments, in step S2, the potential during the deposition reaction is 0.7 - 0.9 V, for example, it can be 0.7 V, 0.8 V or 0.9 V, and the time is 40 - 300 s, for example, it can be 40 s, 50 s, 100 s, 150 s, 200 s, 250 s or 300 s. Among them, when the potential is less than this range, it will lead to insufficient reaction activation energy and the electrodeposition reaction cannot occur. When the potential is greater than this range, it will lead to too intense deposition reaction and uneven deposition.
[0044] According to the second aspect of the present application, the present application provides a nickel-based composite nanozyme prepared by the above steps.
[0045] According to the third aspect of the present application, the present application provides an application of the above nickel-based composite nanozyme. The nickel-based composite nanozyme is used for neurotransmitters, glucose and ascorbic acid in an electrochemical sensor.
[0046] In some embodiments, an application in a nickel-based composite nanozyme electrochemical sensor includes the following steps:
[0047] Step S1: Introduce a buffer solution and a solution to be measured into the microfluidic electrochemical device;
[0048] Step S2: Obtain the sensitivity and detection limit of the sensor according to the current response generated by the nickel-based composite nanozyme on the working electrode;
[0049] Among them, the buffer solution is selected from phosphate buffer solution.
[0050] In some embodiments, the sensitivity and detection limit of the sensor are obtained according to the current response generated by solutions to be measured with different concentrations.
[0051] To make the technical solutions and advantages of the present invention clearer, the present invention and its beneficial effects will be further described in detail below in conjunction with specific embodiments and the accompanying drawings of the specification. However, the embodiments of the present invention are not limited thereto.
[0052] Example 1
[0053] (1) Preparation of nickel-based composite nanozyme
[0054] Step S1, device assembly: Lay the PDMS membrane with microchannels flat on a glass slide ultrasonically cleaned with absolute ethanol and ultrapure water. Place the indium tin oxide glass working electrode with an effective area controlled by UV-cured insulating ink to be 15 mm 2 downward in the microchannels of the PDMS membrane. Fasten the PDMS gland on the PDMS microchannel membrane, and embed the working electrode in the gland. Assemble the silver / silver chloride wire reference electrode and the platinum wire counter electrode, and then insert the inlet tube and the outlet tube to form a microfluidic electrochemical device; as Figure 1 shown.
[0055] Step S2, electrochemical deposition: Inject the electrolyte containing 0.5 mg / mL nickel-based nanomaterial Ni 3 (HHTP) 2 and 100 mM conductive polymer pyrrole into the microfluidic electrochemical device. After applying an electric current for a deposition reaction at a voltage of 0.75 v for 40 s, the nickel-based composite nanozyme Ppy-Ni 3 (HHTP) 2 is formed on the surface of the working electrode. The nickel-based composite nanozyme Ppy-Ni 3 (HHTP) 2 is prepared, and its scanning electron microscope (SEM) characterization diagram, atomic force microscope (AFM) characterization diagram, and X-ray photoelectron spectroscopy (XPS) characterization diagram are as Figures 2 - 4 shown.
[0056] Among them, the volume of the electrolyte in step S2 is 150 μL.
[0057] (2) Application of nickel-based composite nanozyme in electrochemical sensors
[0058] Step S1, introduce phosphoric acid into the microfluidic electrochemical device to configure dopamine solutions with different concentrations (500 nM - 100 μM);
[0059] Step S2, obtain the sensitivity and detection limit of the sensor according to the current response generated by the nickel-based composite nanozyme on the working electrode. The results are as Figure 5 shown.
[0060] Example 2
[0061] The difference from Example 1 is the preparation process of the nickel-based composite nanozyme. In step S2 of this example, the volume of the electrolyte is 100 μL, the concentration of the nickel-based nanomaterial is 0.25 mg / mL, and the concentration of the conductive polymer is 10 mM.
[0062] The rest is the same as Example 1 and will not be elaborated here.
[0063] Example 3
[0064] Different from Example 1 is the preparation process of the nickel-based composite nanozyme. In step S2 of this example, the volume in the electrolyte is 200 μL, the concentration of the nickel-based nanomaterial is 1 mg / mL, and the concentration of the conductive polymer is 200 mM.
[0065] The rest is the same as in Example 1 and will not be elaborated here.
[0066] Example 4
[0067] Different from Example 1 is the preparation process of the nickel-based composite nanozyme. In step S2 of this example, the potential during the deposition reaction is 0.7 V.
[0068] The rest is the same as in Example 1 and will not be elaborated here.
[0069] Example 5
[0070] Different from Example 1 is the preparation process of the nickel-based composite nanozyme. In step S2 of this example, the potential during the deposition reaction is 0.9 V and the time is 300 s.
[0071] The rest is the same as in Example 1 and will not be elaborated here.
[0072] Example 6
[0073] Different from Example 1 is the preparation process of the nickel-based composite nanozyme. In step S2, the conductive polymer is selected from poly(3,4-ethylenedioxythiophene).
[0074] The rest is the same as in Example 1 and will not be elaborated here.
[0075] Example 7
[0076] Different from Example 1 is the application process of the nickel-based composite nanozyme in the electrochemical sensor. In step S1, the test solution is a glucose solution with a concentration of 500 nM - 100 μM.
[0077] The rest is the same as in Example 1 and will not be elaborated here.
[0078] Example 8
[0079] Different from Example 1 is the application process of the nickel-based composite nanozyme in the electrochemical sensor. In step S1, the test solution is an ascorbic acid solution with a concentration of 500 nM - 100 μM.
[0080] The rest is the same as in Example 1 and will not be elaborated here.
[0081] Comparative Example 1
[0082] Different from Example 1 in the preparation process of the nickel-based composite nanozyme, in this comparative example, cysteine and nickel chloride were dissolved in water, and then the pH of the solution was adjusted to 10. After ultrasonic mixing for 15 min to make it uniform, it was placed in a high-pressure hydrothermal reaction kettle and subjected to hydrothermal reaction at 180 °C for 8 h. After the hydrothermal reaction was completed, it was naturally cooled to room temperature, and the obtained reaction solution was subjected to solid-liquid separation to obtain a solid precipitate. The obtained solid precipitate was washed with pure water multiple times and then freeze-dried to obtain nickel-doped carbon nanozyme.
[0083] The rest is the same as that in Example 1 and will not be elaborated here.
[0084] Comparative Example 2
[0085] Different from Example 1 in the preparation process of the nickel-based composite nanozyme, in this comparative example, in step S2, the concentration of the nickel-based nanomaterial in the electrolyte was 2 mg / mL, and the concentration of the conductive polymer was 10 mM.
[0086] The rest is the same as that in Example 1 and will not be elaborated here.
[0087] Comparative Example 3
[0088] Different from Example 1 in the preparation process of the nickel-based composite nanozyme, in this comparative example, in step S2, the concentration of the nickel-based nanomaterial in the electrolyte was 0.25 mg / mL, and the concentration of the conductive polymer was 300 mM.
[0089] The rest is the same as that in Example 1 and will not be elaborated here.
[0090] Comparative Example 4
[0091] Different from Example 1 in the preparation process of the nickel-based composite nanozyme, in this comparative example, in step S2 during the deposition reaction, the potential was 1.5 V.
[0092] The rest is the same as that in Example 1 and will not be elaborated here.
[0093] Comparative Example 5
[0094] Different from Example 1 in the preparation process of the nickel-based composite nanozyme, in this comparative example, in step S2 during the deposition reaction, the time was 20 s.
[0095] The rest is the same as that in Example 1 and will not be elaborated here.
[0096] From the comparison between Example 1 and Comparative Example 1, it can be obtained that the preparation process of the nickel-based composite nanozyme synthesized by the conventional chemical method is complex, the synthesis conditions are relatively harsh, and the time consumption is long. However, the preparation method of the nickel-based composite nanozyme provided in this application can simply control the synthesis rate by changing the composition and concentration of the electrolyte and the type and magnitude of the electrical signal without a high-temperature and high-pressure environment, and its energy consumption is significantly reduced, which is more green and safe.
[0097] According to Figures 2 - 4 the characterization diagram of the nickel-based composite nanozyme, it can be seen that the nickel-based composite nanozyme prepared in the present invention has a large specific surface area, good electron transfer performance and excellent electrocatalytic performance. According to Figure 5 the sensitivity and detection limit of the nickel-based composite nanozyme prepared in Example 1 as a sensor in the microfluidic electrochemical device, it can be seen that the nickel-based composite nanozyme prepared in this application can solve the problems of high synthesis conditions, long time consumption, uneven modification of the existing nickel-based composite nanozyme, complex equipment and large sample demand during detection.
[0098] According to the disclosure and teachings of the above specification, those skilled in the art to which the present invention pertains can also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the above specific embodiments, and any obvious improvements, substitutions or variations made by those skilled in the art on the basis of the present invention all fall within the protection scope of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.
Claims
1. A method for preparing a nickel-based composite nanozyme, characterized in that: The following steps are involved: Step S1, device assembly: lay the PDMS membrane containing the microfluidic channel flat on a glass slide, place the working electrode with the working area facing downward in the microfluidic channel of the PDMS membrane, buckle the PDMS gland on the PDMS microfluidic channel membrane, and embed the working electrode in the gland, assemble the reference electrode and the counter electrode, and then insert the liquid inlet and outlet tubes to form a microfluidic electrochemical device; Step S2, electrochemical deposition: injecting an electrolyte containing nickel-based nanomaterials and a conductive polymer into the microfluidic electrochemical device, and forming the nickel-based composite nanozyme on the surface of the working electrode after an electrodeposition reaction.
2. The method for preparing the nickel-based composite nanozyme according to claim 1, characterized in that: In step S1, the working electrode is selected from at least one of indium tin oxide glass, a gold electrode and a glassy carbon electrode.
3. The method for preparing the nickel-based composite nanozyme according to claim 1, characterized in that: In step S2, the nickel-based nanomaterial is selected from Ni3(HHTP)2.
4. The method for preparing the nickel-based composite nanozyme according to claim 1, characterized in that: The conductive polymer is selected from at least one of polypyrrole, polyaniline and poly (3,4-ethylenedioxythiophene).
5. The method for preparing the nickel-based composite nanozyme according to claim 1 or 3, characterized in that: In step S2, the volume of the electrolyte is 100-200 μL.
6. The method for preparing the nickel-based composite nanozyme according to claim 1, characterized in that: In step S2, the concentration of the nickel-based nanomaterial in the electrolyte is 0.25-1 mg / mL, and the concentration of the conductive polymer is 10-200 mM.
7. The method for preparing the nickel-based composite nanozyme according to claim 1, characterized in that: In step S2, the deposition reaction is carried out at a potential of 0.7-0.9 V and for a time of 40-300 s.
8. A nickel-based composite nanozyme, characterized in that: The nickel-based composite nanozyme is prepared by the preparation method according to any one of claims 1 to 7.
9. An application of a nickel-based composite nanozyme, characterized in that: The nickel-based composite nanozyme described in claim 8 is used in electrochemical sensors for neurotransmitters, glucose and ascorbic acid.
10. The use of the nickel-based composite nanozyme according to claim 9, characterized in that: The following steps are involved: Step S1, introducing a test solution prepared in a buffer solution into the microfluidic electrochemical device; Step S2, obtaining the sensitivity and detection limit of the sensor according to the current response generated by the nickel-based composite nanozyme catalyzing the analyte on the working electrode; Wherein, the buffer is selected from phosphate buffer.