Electrocatalytic urea synthesis system and method based on DNA nanoreactor

Abstract

The invention discloses an electrocatalytic urea synthesis system and method based on a DNA nano-reactor, and belongs to the crossing field of electrochemical catalysis and nano-biotechnology. The system comprises a DNA nanoreactor, a catalytic activity center, an electrochemical device, an electric field regulation and control system and an in-situ monitoring and feedback system, the DNA nanoreactor adopts a DNA origami technology to construct a three-dimensional hollow structure and loads bimetallic nanoparticles, and efficient synthesis of urea is realized by accurately controlling reaction conditions. The local concentration of reactants is remarkably improved through the confinement effect and the molecular recognition function of the DNA nanostructure, the Faraday efficiency and the yield of urea are effectively improved, the reaction potential is reduced, and meanwhile accurate regulation and control of the reaction process are achieved through an intelligent monitoring system. The system can operate under the conditions of normal temperature and normal pressure, is suitable for resource utilization of industrial wastewater nitrate, has the characteristics of low energy consumption, environmental friendliness and the like, meets the requirements of green chemical development, and conforms to the national double-carbon policy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electrochemical catalysis and nanobiotechnology, in particular to an electrocatalytic urea synthesis system and method based on a DNA nanoreactor, which is suitable for efficient, low-energy green synthesis of urea and resource utilization of wastewater nitrate. BACKGROUND

[0002] Urea is the most widely used nitrogen fertilizer in the world. The current industrial system uses the Bosch-Meiser process to produce urea. The raw material ammonia (NH3) is prepared by the high-energy Haber-Bosch process, and carbon dioxide (CO2) is derived from the steam methane reforming process, which also has high emissions. These two processes not only require harsh conditions of high temperature and high pressure, but also consume 1% of the global energy supply every year and produce more than 200 million tons of CO2 net emissions, becoming an important source of energy consumption and greenhouse gas emissions.

[0003] Electrocatalytic urea synthesis technology is considered a revolutionary alternative to traditional processes due to its mild reaction conditions and environmental friendliness. Currently, the field of electrocatalytic urea synthesis faces two major challenges: the instability of DNA nanostructures and low mass transfer and reaction efficiency. In biomolecular reactors, the stability of DNA structures in electrochemical environments is severely threatened. In addition, traditional immobilization methods such as Au-S bonding cause DNA structures to adhere closely to the electrode surface, resulting in steric hindrance effects that hinder the approach of reactants to active sites.

[0004] In existing solutions, microfluidic reactor technology can improve mass transfer, but its channel size is much larger than that of DNA structures, making it impossible to achieve precise confinement. At the same time, high pressure drop can cause mechanical damage to DNA structures. In terms of biological-electrochemical interface optimization, the technology of carbon nanotube forest electrodes loaded with DNAzyme has the problem of uneven distribution of active sites, and does not solve the problem of DNA denaturation induced by electric field. Another technology stabilizes G-quadruplexes through a fixed frequency AC electric field (1 kHz), but cannot adapt to the needs of different reaction stages, and lacks an in-situ monitoring module.

[0005] Therefore, it is of great significance to develop an electrocatalytic urea synthesis system that can efficiently catalyze C-N coupling, reduce reaction overpotential, and realize CO2 and NO3 - resource utilization, to promote the development of green chemical industry and achieve the "double carbon" goal. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application provides an electrocatalytic urea synthesis system and method based on a DNA nanoreactor. The catalyst obtained using the system has excellent Faraday efficiency and high urea synthesis yield.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: an electrocatalytic urea synthesis system and method based on a DNA nanoreactor, comprising a DNA nanoreactor, a catalytic active center, an electrochemical device, an electric field control system, and an in-situ monitoring and feedback system;

[0008] The DNA nanoreactor is a three-dimensional hollow structure constructed based on DNA origami technology, presenting a precise polyhedral geometric configuration. By designing a specific sequence of DNA single strands (72-mer stapled chains), it self-assembles to form an icosahedral rigid framework. The structural stability is significantly enhanced by introducing five cross-chains (three stapled chains are added to each DNA bundle), and it can withstand a 0.3MPa fluid shear force. The inner wall is modified with specific functional groups (amino, carboxyl, thiol groups, with a density of 12 / 100nm). 2 ), can selectively enrich reactant molecules such as CO2 and nitrogen-containing compounds, with a cavity size of 5-50nm, a wall thickness of 3.2nm (composed of cross-arranged DNA double helices), and a vertex angle error controlled within ±5° (confirmed by cryo-electron microscopy 3D reconstruction);

[0009] The catalytic active center refers to the loading of bimetallic nanoparticles at specific sites of the DNA nanoreactor, with the particle size controlled within the range of 2-10 nm, for synergistic activation of reactants;

[0010] The electrochemical device includes a working electrode (DNA nanoreactor modified electrode), a counter electrode and a reference electrode, and the electrolyte contains 0.1-0.5M KHCO3 and 0.05-0.2M KNO3, with a pH of 7-9;

[0011] The electric field control system adopts a multi-electrode array design, including working electrodes, counter electrodes, and reference electrodes, and is equipped with an intelligent electric field generator. It can output programmable waveforms (frequency 1-100Hz, voltage ±0.1-0.5V), waveform duty cycle 10-90%, potential scan rate 1-100mV / s, and automatically adjust parameters for different reaction stages. The working potential is controlled within a range of 0.2-0.4V lower than traditional methods, with a potential control error of ±5mV and a current density control error of ±0.5mA / cm 2 , response time <100ms;

[0012] The in-situ monitoring and feedback system includes a FRET probe system, an SPR sensor, and a microelectrode array. The reaction parameters are dynamically adjusted through a closed-loop control algorithm. The data acquisition frequency is 100-1000 Hz, the control algorithm update cycle is 0.1-1.0 s, the parameter adjustment accuracy is ±1%, and the system delay is <50 ms.

[0013] The present invention also discloses an electrocatalytic urea synthesis method based on the above system, comprising the following steps:

[0014] Step 1: The DNA nanoreactor is modified to the surface of the conductive substrate by covalent bonding to construct a working electrode. The DNA nanoreactor is prepared by self-assembly technology, with M13mp18 single-stranded DNA (7249 nt) as the backbone, and 72 stapled chains (42-52 nt) are used to form a working electrode on the surface of the conductive substrate. 2+ The icosahedral structure (25 nm in diameter, 3.2 nm in wall thickness) was formed by gradient annealing at 95°C → 65°C → 25°C in buffer. The inner wall was modified with amino, carboxyl and thiol groups (12 / 100 nm). 2 ), the cavity size is adjustable from 5 to 50 nm, and the conductive substrate is made of carbon-based or metal-based materials;

[0015] Step 2: Prepare a reaction electrolyte containing a carbon source and a nitrogen source, wherein the carbon source is high-purity carbon dioxide gas (99.999%), and the nitrogen source is a nitrate-containing compound, wherein the main nitrogen source is 0.1M KNO3, and the alternative nitrogen source is a NO3-containing compound. - The anti-interference performance was verified by adding 0.1M NaCl to simulated wastewater (50-200ppm) and adjusting the electrolyte pH to 7-9 through the buffer system to maintain stable ionic strength and conductivity.

[0016] Step 3: At 25-45°C and 0.1-0.3 MPa, apply a working potential of -0.4 to -0.8 V (vs. RHE) and drive the electrocatalytic reaction in a constant potential mode with a current density of 10-50 mA / cm 2 ;

[0017] Step 4: The reaction progress is tracked in real time using an in situ monitoring system. FRET probes are used to label the DNA framework and detect the dynamics of urea formation (sensitivity 0.1-0.8 μM, response time less than 45 seconds). The electric field parameters, including potential, application method, and duration, are dynamically adjusted.

[0018] Step 5: After the reaction is completed, the DNA carrier is removed by ultrafiltration and centrifugation, urea is enriched by solid phase extraction, and the urea yield is quantitatively detected by high performance liquid chromatography to calculate the Faradaic efficiency.

[0019] The present invention has the following advantages:

[0020] 1. The icosahedral nanoreactor constructed based on DNA origami technology has its inner wall modified with specific functional groups (amino, carboxyl, and thiol groups), which can achieve selective enrichment of reactant molecules such as CO2 and nitrogen-containing compounds. The confinement effect and molecular recognition function of the nanoreactor can significantly increase the local concentration of reactants, effectively improving the Faradaic efficiency and yield of urea by 2-3 times compared with traditional methods;

[0021] 2. The bimetallic synergistic catalytic system loaded by specific sites of DNA backbone can effectively promote C-N coupling reaction, the reaction potential is reduced by 0.2-0.4V, and the energy consumption is significantly reduced;

[0022] 3. The intelligent monitoring feedback system can realize precise regulation of the reaction process, and ensure that the system is always in the optimal working state;

[0023] 4. The nitrate in industrial wastewater can be used as a nitrogen source to realize the resource utilization of pollutants;

[0024] 5. The whole system operates under mild conditions (normal temperature and pressure), and the carbon source uses industrial captured CO2 (purity ≥ 99.99%), which meets the requirements of green chemistry development. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0026] Figure 1 It is a structural schematic diagram of the present application.

[0027] Figure 2 It is a urea yield and Faraday efficiency diagram of Cu-Pd bimetallic catalyst in embodiment one of the present application. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0029] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

[0030] Embodiment one

[0031] A DNA nanoreactor-based electrocatalytic urea synthesis system and method, comprising a DNA nanoreactor, a catalytically active center, an electrochemical device, an electric field regulation system, and an in-situ monitoring and feedback system.

[0032] The DNA nanoreactor is a three-dimensional hollow structure based on DNA origami technology, forming a regular geometric structure of icosahedron, with the inner wall modified with specific functional groups (amino, carboxyl, thiol), which can selectively enrich CO2 and nitrogen-containing compound reactant molecules, and the cavity size is 20 nm.

[0033] The catalytically active center refers to a bimetallic nanoparticle loaded at a specific site of the DNA backbone, using a Cu-Pd (copper-palladium ratio 2:1-1:2) bimetallic system, with a particle size controlled within 3-6 nm, for the synergistic activation of reactants, with a loading density of 15 / 100 nm 2 DNA area;

[0034] The electrochemical device includes a working electrode (DNA nanoreactor modified electrode, carbon paper substrate, loading capacity 0.5 mg / cm 2 ), a counter electrode (platinum mesh or graphite rod), and a reference electrode (Ag / AgCl, filled with saturated KCl solution), and an electrolyte containing 0.25 M KHCO3 and 0.1 M KNO3, with a pH value of 7.0-8.0;

[0035] The electric field regulation system adopts a multi-electrode array design, including a working electrode, a counter electrode, and a reference electrode, and is equipped with an intelligent electric field generator, which can output programmable waveforms (frequency 10-50 Hz, voltage ±0.3 V), with a duty cycle of 90%, a potential scanning rate of 50 mV / s, and automatically adjusting parameters for different reaction stages, with a working potential control within a range of 0.2-0.4 V lower than traditional methods, a potential control error of ±5 mV, and a current density control error of ±0.5 mA / cm 2 , with a response time of <100 ms;

[0036] The in-situ monitoring and feedback system includes a FRET probe system (sensitivity 0.1-1.0%, response time 1-10 s), an SPR sensor (resolution 0.001-0.010°, corresponding concentration 0.1-1.0 μM, sampling frequency 10-100 Hz), and a microelectrode array (electrode diameter 50 μm, spacing 500 μm, response time 1-10 ms), which dynamically adjusts reaction parameters through a closed-loop control algorithm, with a data acquisition frequency of 100-1000 Hz, a control algorithm update period of 0.1-1.0 s, a parameter adjustment accuracy of ±1%, and a system delay of <50 ms.

[0037] A DNA nanoreactor-based electrocatalytic urea synthesis system and method, comprising the following steps:

[0038] Step 1: First, a high-purity carbon paper substrate (thickness 500 μm) was pretreated and ultrasonically cleaned with acetone, ethanol, and ultrapure water (30 kHz, 20 min), dried with nitrogen, and then vacuum-dried at 80°C for 3 h. The prepared DNA nanoreactor was then dispersed in PBS buffer (10 mM, pH 7.4) and coated using a drop coating method (control loading 0.5-1.5 mg / cm 2 ) for loading and finally fixed with 0.5% Nafion solution to form a uniform modified layer.

[0039] Step 2: Accurately weigh KHCO₃ (0.25 M) and KNO₃ (0.1 M), dissolve them in ultrapure water (resistivity ≥ 18.2 MΩ·cm), and stir magnetically (400 rpm) for 40 min until completely dissolved. Adjust the pH to 7.5 (accuracy ±0.1) with 0.1 M KOH solution. Then, introduce high-purity CO₂ (purity ≥ 99.99%, 50 mL / min) until saturated (45 min), maintaining a gentle CO₂ bubbling (10 mL / min).

[0040] Step 3. Assemble the reaction system using an H-type electrolytic cell separated by a Nafion membrane (type 117). Maintain a 3.0 cm distance between the working electrode and the counter electrode, and a 5 mm distance between the tip of the reference electrode capillary and the working electrode. Set the reaction temperature to 30°C (accuracy ±0.5°C), the pressure to 0.20 MPa (accuracy ±0.01 MPa), the operating potential to -0.40 to -0.80 V (vs. RHE, accuracy ±5 mV), and maintain magnetic stirring (300 rpm).

[0041] Step 4: FRET probe (fluorescence signal collected every 3 min), SPR sensor (sampling frequency 8 Hz) and microelectrode array (resolution 0.1 mA / cm 2 ) for in-situ monitoring. Based on the monitoring data, a PID algorithm was used to dynamically adjust the reaction parameters: potential adjustment range ±10-50mV, frequency adjustment range ±1-10Hz, and temperature adjustment range ±0.5-1.0°C. Comprehensive parameter optimization was performed every 10 minutes.

[0042] Step 5: After 5 h of reaction, samples were collected and filtered through a 0.22 μm filter to remove the DNA carrier. Urea was enriched by solid-phase extraction and stored at -20°C. Urea was quantified using high-performance liquid chromatography (HPLC, C18 column, UV detector at 210 nm) and Faradaic efficiency was calculated. All operations were performed under an inert atmosphere (e.g., Ar) to ensure the accuracy of the experimental results.

[0043] Example 2

[0044] A DNA nanoreactor-based electrocatalytic urea synthesis system and method, comprising a DNA nanoreactor, a catalytically active center, an electrochemical device, an electric field regulation system, and an in-situ monitoring and feedback system;

[0045] The DNA nanoreactor is a three-dimensional hollow structure based on DNA origami technology, forming a regular geometric structure of icosahedron, with the inner wall modified with specific functional groups (amino, carboxyl, thiol), which can selectively enrich CO2 and nitrogen-containing compound reactant molecules, and the cavity size is 30 nm;

[0046] The catalytically active center refers to a bimetallic nanoparticle loaded at a specific site of the DNA backbone, using a Cu-Zn (copper-zinc ratio 3:1-1:3) bimetallic system, with a particle size controlled within 6-9 nm, for the synergistic activation of reactants, with a loading density of 20 / 100 nm 2 DNA area;

[0047] The electrochemical device includes a working electrode (DNA nanoreactor modified electrode, carbon paper substrate, loading capacity 1.0 mg / cm 2 ), a counter electrode (platinum mesh or graphite rod), and a reference electrode (Ag / AgCl, filled with saturated HCl solution), and an electrolyte containing 0.35M KHCO3 and 0.2M KNO3, with a pH value of 7.5-8.5;

[0048] The electric field regulation system adopts a multi-electrode array design, including a working electrode, a counter electrode, and a reference electrode, and is equipped with an intelligent electric field generator, which can output programmable waveforms (frequency 60 Hz, voltage ±0.3V), with a duty cycle of 80%, a potential scanning rate of 80 mV / s, and automatically adjusting parameters for different reaction stages, with a working potential controlled within a range of 0.2-0.4V lower than traditional methods, a potential control error of ±5mV, and a current density control error of ±0.5mA / cm 2 , with a response time <100ms;

[0049] The in-situ monitoring and feedback system includes a FRET probe system (sensitivity 0.1-1.0%, response time 1-10s), an SPR sensor (resolution 0.001-0.010°, corresponding concentration 0.1-1.0μM, sampling frequency 10-100Hz), and a microelectrode array (electrode diameter 30μm, spacing 300μm, response time 1-10ms), which dynamically adjusts reaction parameters through a closed-loop control algorithm, with a data acquisition frequency of 100-1000Hz, a control algorithm update period of 0.1-1.0s, a parameter adjustment accuracy of ±1%, and a system delay <50ms;

[0050] A DNA nanoreactor-based electrocatalytic urea synthesis system and method, comprising the following steps:

[0051] Step 1: First, a high-purity carbon paper substrate (thickness 300 μm) was pretreated and ultrasonically cleaned with acetone, ethanol, and ultrapure water (40 kHz, 15 min), dried with nitrogen, and then vacuum-dried at 100°C for 4 h. The prepared DNA nanoreactor was then dispersed in PBS buffer (10 mM, pH 8.0) and coated using a drop coating method (control loading 1.5-2.0 mg / cm 2 ) for loading and finally fixed with 0.3% Nafion solution to form a uniform modified layer.

[0052] Step 2: Accurately weigh KHCO₃ (0.35 M) and KNO₃ (0.2 M), dissolve them in ultrapure water (resistivity ≥ 18.2 MΩ·cm), and stir magnetically (600 rpm) for 60 min until completely dissolved. Adjust the pH to 8.0 (accuracy ±0.1) with 0.1 M HCl solution. Then, introduce high-purity CO₂ (purity ≥ 99.99%, 30 mL / min) until saturated (60 min), maintaining a gentle CO₂ bubbling (8 mL / min).

[0053] Step 3. Assemble the reaction system using an H-type electrolytic cell separated by a Nafion membrane (type 117). Maintain a 3.0 cm distance between the working electrode and the counter electrode, and a 4 mm distance between the tip of the reference electrode capillary and the working electrode. Set the reaction temperature to 35.0°C (accuracy ±0.5°C), the pressure to 0.15 MPa (accuracy ±0.01 MPa), the operating potential to -0.40 to -0.80 V (vs. RHE, accuracy ±5 mV), and maintain magnetic stirring (200 rpm).

[0054] Step 4: FRET probe (fluorescence signal collected every 5 min), SPR sensor (sampling frequency 10 Hz) and microelectrode array (resolution 0.1 mA / cm 2 ) for in-situ monitoring. Based on the monitoring data, a PID algorithm was used to dynamically adjust the reaction parameters: potential adjustment range ±10-20mV, frequency adjustment range ±1-15Hz, and temperature adjustment range ±1.5-2.0°C. Comprehensive parameter optimization was performed every 15 minutes.

[0055] Step 5: After 6 hours of reaction, samples were collected and filtered through a 0.22 μm filter to remove the DNA carrier. Urea was enriched by solid-phase extraction and stored at -5°C. Urea was quantified using high-performance liquid chromatography (HPLC, C18 column, UV detector at 210 nm) and Faradaic efficiency was calculated. All operations were performed under an inert atmosphere (e.g., Ar) to ensure the accuracy of the experimental results.

Claims

1. A DNA nanoreactor-based electrocatalytic urea synthesis system and method, characterized in that: It includes DNA nanoreactor, catalytic active center, electrochemical device, electric field control system and in-situ monitoring and feedback system.

2. The electrocatalytic urea synthesis system and method based on DNA nanoreactor according to claim 1, characterized in that: The DNA nanoreactor is a three-dimensional hollow structure constructed based on DNA origami technology, presenting a precise polyhedral geometric configuration. By designing a specific sequence of DNA single strands (72-mer stapled chains), it self-assembles to form an icosahedral rigid framework. The structural stability is significantly enhanced by introducing five cross-chains (three stapled chains are added to each DNA bundle), and it can withstand a 0.3MPa fluid shear force. The inner wall is modified with specific functional groups (amino, carboxyl, thiol groups, with a density of 12 / 100nm). 2 ), can selectively enrich reactant molecules such as CO2 and nitrogen-containing compounds, the cavity size is 5-50nm, the wall thickness is 3.2nm (composed of cross-arranged DNA double helices), and the vertex angle error is controlled within ±5° (confirmed by cryo-electron microscopy three-dimensional reconstruction).

3. The electrocatalytic urea synthesis system and method based on DNA nanoreactor according to claim 1, characterized in that: The catalytic active center refers to the bimetallic nanoparticles loaded at specific sites of the DNA nanoreactor, with the particle size controlled within the range of 2-10 nm, for synergistic activation of reactants.

4. The electrocatalytic urea synthesis system and method based on DNA nanoreactor according to claim 1, characterized in that: The electrochemical device includes a working electrode (DNA nanoreactor modified electrode), a counter electrode and a reference electrode. The electrolyte contains 0.1-0.5M KHCO3 and 0.05-0.2M KNO3, and the pH is 7-9.

5. The electrocatalytic urea synthesis system and method based on DNA nanoreactor according to claim 1, characterized in that: The electric field control system adopts a multi-electrode array design, including working electrodes, counter electrodes, and reference electrodes, and is equipped with an intelligent electric field generator. It can output programmable waveforms (frequency 1-100Hz, voltage ±0.1-0.5V), waveform duty cycle 10-90%, potential scan rate 1-100mV / s, and automatically adjust parameters for different reaction stages. The working potential is controlled within a range of 0.2-0.4V lower than traditional methods, with a potential control error of ±5mV and a current density control error of ±0.5mA / cm 2 , response time <100ms.

6. The electrocatalytic urea synthesis system and method based on DNA nanoreactor according to claim 1, characterized in that: The in-situ monitoring and feedback system includes a FRET probe system, an SPR sensor, and a microelectrode array. The reaction parameters are dynamically adjusted through a closed-loop control algorithm. The data acquisition frequency is 100-1000Hz, the control algorithm update period is 0.1-1.0s, the parameter adjustment accuracy is ±1%, and the system delay is <50ms.

7. The electrocatalytic urea synthesis system and method based on DNA nanoreactor according to claim 1, characterized in that: The method comprises the following steps: Step 1: The DNA nanoreactor is modified to the surface of the conductive substrate by covalent bonding to construct a working electrode. The DNA nanoreactor is prepared by self-assembly technology, with M13mp18 single-stranded DNA (7249 nt) as the backbone, and 72 stapled chains (42-52 nt) are used to form a working electrode on the surface of the conductive substrate. 2+ The icosahedral structure (25 nm in diameter, 3.2 nm in wall thickness) was formed by gradient annealing at 95°C → 65°C → 25°C in buffer. The inner wall was modified with amino, carboxyl and thiol groups (12 / 100 nm). 2 ), the cavity size is adjustable from 5 to 50 nm, and the conductive substrate is made of carbon-based or metal-based materials; Step 2: Prepare a reaction electrolyte containing a carbon source and a nitrogen source, wherein the carbon source is high-purity carbon dioxide gas (99.999%), and the nitrogen source is a nitrate-containing compound, wherein the main nitrogen source is 0.1M KNO3, and the alternative nitrogen source is a NO3-containing compound. - The anti-interference performance was verified by adding 0.1M NaCl to simulated wastewater (50-200ppm) and adjusting the electrolyte pH to 7-9 through the buffer system to maintain stable ionic strength and conductivity. Step 3: At 25-45°C and 0.1-0.3 MPa, apply a working potential of -0.4 to -0.8 V (vs. RHE) and drive the electrocatalytic reaction in a constant potential mode with a current density of 10-50 mA / cm 2 ; Step 4: The reaction progress is tracked in real time using an in situ monitoring system. FRET probes are used to label the DNA framework and detect the dynamics of urea formation (sensitivity 0.1-0.8 μM, response time less than 45 seconds). The electric field parameters, including potential, application method, and duration, are dynamically adjusted. Step 5: After the reaction is completed, the DNA carrier is removed by ultrafiltration and centrifugation, urea is enriched by solid phase extraction, and the urea yield is quantitatively detected by high performance liquid chromatography to calculate the Faradaic efficiency.

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