Preparation method of high-sensitivity rutin electrochemical sensor and electrochemical sensor prepared thereby

Abstract

The application relates to a preparation method of a high-sensitivity rutin electrochemical sensor and the prepared electrochemical sensor. A rutin electrochemical sensing electrode modified by a Ti3C2-CNTs-Au / CD-MOF-CNTs nanometer material composite is constructed, and the electrochemical sensing electrode is used for rapid detection of the rutin content in buckwheat and orange juice samples. The sensor has the advantages of fast detection speed, convenient operation, low cost and real-time monitoring. The rutin sensor prepared by the application has the advantages of a wide linear range and a low detection limit, and has good selectivity under the condition of the existence of interfering substances.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of electrochemical detection, and in particular to a preparation method of a high-sensitivity rutin electrochemical sensor based on Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE. BACKGROUND

[0002] Rutin (Ru) belongs to a group of naturally occurring flavonoids, which are widely present in various plants, such as buckwheat, and locust tree. Importantly, rutin has a series of physiological activities, such as antioxidant, antiviral, anti-inflammatory, anticancer and antitumor, and is also often used for clinical treatment of some diseases, including diabetes, hypertension, senile dementia and neuroinflammation. Therefore, it is very necessary to develop a rapid and effective technology to detect and quantify rutin in plants and medicines.

[0003] Some commonly used analytical methods, such as high performance liquid chromatography, capillary electrophoresis and spectrophotometry, have been used for the determination of rutin. However, some of these methods are time-consuming, high-cost or require complex pretreatment processes, which hinders their further application. Compared with these methods, electrochemical determination method has the advantages of good reliability, fast reaction, inexpensive instrument, low energy consumption, simple operation, time saving, high sensitivity and strong selectivity, and especially its equipment is portable and can be determined on site. In recent years, with the development of nanoscience and nanotechnology, many nanomaterial electrodes capable of significantly improving the signal strength of electrochemical sensors and realizing ultra-sensitive determination have been applied to the electrochemical determination of rutin. However, according to the investigation, it is still a challenge to use two-dimensional (2D) materials to manufacture new type electrochemical sensors to realize sensitive, rapid and simple detection of rutin.

[0004] Transition metal carbides (MXenes) as a new type of two-dimensional (2D) layered material are obtained by selective etching of A layer in MAX phase (M is an early transition metal, A basically refers to elements in group 13 to 14, and X represents C / or N). It was first synthesized by Michael Naguib and his colleagues in 2011. MXene material has good conductivity, good structural / chemical stability and a large number of redox active sites, which makes it have broad application prospects in the fields of energy storage, biomedicine, optics and the like. Among them, Ti3C2 is a typical representative of MXene phase material. Due to its excellent metal conductivity, hydrophilicity and surface group adjustable performance, Ti3C2 shows good application prospect in electrochemical sensing.

[0005] Alkali metal ion and cyclodextrin (CD) based cyclodextrin-metal-organic framework (CD-MOF) has been reported as a new green MOF. Due to the unique adsorption and encapsulation ability of CD-MOF, it is often used as a carrier and adsorbent. However, the application of CD-MOF in the field of electrochemical sensors is rarely reported. Therefore, it is novel to improve the sensitivity and detection capability of the sensor by the strong enrichment performance of CD-MOF. SUMMARY

[0006] The application provides a preparation method of a high-sensitivity rutin electrochemical sensor based on Ti3C2-CNTs-Au / CD-MOF-CNTs, which can effectively solve the problems of low electrocatalytic activity and low sensitivity in the rutin detection process.

[0007] The application achieves the above-mentioned technical effects by adopting the following technical solutions.

[0008] The application provides a preparation method of a high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs, which comprises the following steps:

[0009] (1) Multi-layer Ti3C2 MXene synthesis: Ti3AlC2 is dispersed in HF at room temperature, and the obtained solid product is washed with ultrapure water under continuous stirring until the pH value of the supernatant reaches 5.5-6.5, and then dried to obtain multi-layer Ti3C2 MXene;

[0010] (2) Preparation of Ti3C2-CNTs-Au: The multi-layer Ti3C2 MXene prepared in step (1) and acidized multi-walled carbon nanotubes are dispersed in deionized water, and then chloroauric acid solution and NaBH4 are sequentially added thereto under stirring, the product is collected by centrifugation at room temperature and washed with water and ethanol for several times, and finally dried to obtain Ti3C2-CNTs-Au;

[0011] (3) Preparation of CD-MOF-CNTs: gamma-cyclodextrin and KOH are added to water and dispersed and dissolved, a filter membrane is used for filtration, methanol is diffused into the filtrate by diffusion method for several days, after the diffusion is completed, the supernatant is collected, and acidized multi-walled carbon nanotubes are added, after dispersion, cetyltrimethylammonium bromide is added and incubated, and finally the precipitate is collected by centrifugation to obtain CD-MOF-CNTs;

[0012] (4) The Ti3C2-CNTs-Au and CD-MOF-CNTs are mixed with the dispersion liquid and dispersed to obtain a dispersion liquid, then the Ti3C2-CNTs-Au dispersion liquid and the CD-MOF-CNTs dispersion liquid are mixed to obtain a composite material, and the mixed composite material is drop-coated on the surface of a clean glassy carbon electrode and dried to obtain a modified electrode.

[0013] The preparation method of the high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs of the application, the dispersion liquid in step (4) is N,N-dimethylformamide.

[0014] The preparation method of the high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs of the application, the dispersion in step (2), step (3) and step (4) is dispersed by ultrasonic.

[0015] The preparation method of the high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs of the application, the clean glassy carbon electrode surface in step (4) is realized by the following method: polishing the glassy carbon electrode with Al2O3 powder, then placing the glassy carbon electrode in ethanol and ultrapure water for ultrasonic washing using an ultrasonic cleaner, and then drying under an infrared lamp to obtain a clean glassy carbon electrode.

[0016] The preparation method of the high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs of the application, the pH value of the supernatant in step (1) is 6.

[0017] The preparation method of the high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs of the application, the modified electrode is obtained by infrared drying in step (4).

[0018] The preparation method of the high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs of the application, the incubation in step (3) is carried out at room temperature, and the time is 2.5-4 hours.

[0019] The preparation method of the high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs of the application, the concentration of the dispersion liquid of Ti3C2-CNTs-Au and CD-MOF-CNTs in step (4) is 1-4 mg / mL, and the volume ratio of the Ti3C2-CNTs-Au dispersion liquid and the CD-MOF-CNTs dispersion liquid when mixed is 2-4:1.

[0020] The application further provides a high-sensitivity rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs, which is prepared by the preparation method, and takes the Ti3C2-CNTs-Au / CD-MOF-CNTs modified electrode as a working electrode, a graphite electrode or a platinum wire electrode as a counter electrode, and an Ag / AgCl electrode as a reference electrode, with a potential range of 0.1V-0.8V, a scanning amplitude of 50mV, a pulse width of 200ms and an environment solution of a phosphate buffer solution with pH=5.8-6.2.

[0021] The application further provides an application of the electrochemical sensor in measuring the concentration of rutin.

[0022] The application has the following beneficial effects:

[0023] When the rutin electrochemical sensing electrode modified by the Ti3C2-CNTs-Au / CD-MOF-CNTs nanometer material composite is used for rapid detection of the rutin content in buckwheat and orange juice samples (i.e. actual natural plant samples), the sensor has the advantages of fast detection speed, convenient operation, low cost and real-time monitoring; the rutin sensor prepared by the application has a linear range of 2nM-800nM, a detection limit of 0.6nM (a signal-to-noise ratio of 3), and does not cause interference to the detection of rutin in the presence of cysteine, quercetin, baicalein, daidzein, morin and apigenin interferents, so that the rutin sensor has a wide linear range, a low detection limit and good selectivity. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figures la-le respectively, SEM images of Ti3C2 MXene, CD-MOF-1, Ti3C2-CNTs-Au, CD-MOF-CNTs and Ti3C2-CNTs-Au / CD-MOF-CNTs;

[0025] Figure 2 are respectively impedance spectra of bare GCE, Ti3C2 / GCE, Ti3C2-CNTs-Au / GCE, CD-MOF-1 / GCE, CD-MOF-CNTs / GCE and Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE in 5mM [Fe(CN)6]3- / 4- solution containing 0.1M KCl;

[0026] Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE in 0.1M PBS (pH=6.0) under different rutin concentrations (2nM-800μM);

[0027] Figure 3 are respectively DPV responses of Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE under different rutin concentrations (2nM-800μM) in 0.1M PBS (pH=6.0);

[0028] Figure 4The linear relationship curve diagram between the steady-state current and the rutin concentration;

[0029] Figure 5 The repeatability test of the sensor prepared by the Ti3C2-CNTs-Au / CD-MOF-CNTs modified electrode for detecting rutin in 0.1M PBS buffer solution containing 100 nM Ru and having a pH of 6.0;

[0030] Figure 6 The repeatability test of the sensor prepared by the Ti3C2-CNTs-Au / CD-MOF-CNTs modified electrode for detecting rutin in 0.1M PBS buffer solution containing 100 nM Ru and having a pH of 6.0;

[0031] Figure 7 The stability test of the sensor prepared by the Ti3C2-CNTs-Au / CD-MOF-CNTs modified electrode for detecting rutin in 0.1M PBS buffer solution containing 100 nM Ru and having a pH of 6.0;

[0032] Figure 8 The anti-interference ability of the sensor is verified by adding various interference substances in 0.1M PBS buffer solution containing 120 nM Ru and having a pH of 6.0, and detecting the change of the peak current by the DPV technology. DETAILED DESCRIPTION

[0033] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application.

[0034] Example 1

[0035] The embodiments of the present application provide a preparation method of a high-sensitivity rutin electrochemical sensor of Ti3C2-CNTs-Au / CD-MOF-CNTs, which comprises the following steps:

[0036] (1) Synthesis of multi-layer Ti3C2 MXene: The multi-layer Ti3C2 is generated by immersing Ti3AlC2 in HF at room temperature, and the aluminum element is selectively etched by HF. First, 1 gram of Ti3AlC2 is dispersed in 20 milliliters of HF, and continuously stirred at room temperature for 36 hours. Next, the obtained product is washed several times with ultrapure water until the pH value of the supernatant reaches 6, so as to remove the excess HF. Finally, the multi-layer Ti3C2 is collected and dried.

[0037] (2) Preparation of Ti3C2-CNTs-Au: 25 mg of multilayer Ti3C2 MXene and 25 mg of acidified multi-walled carbon nanotubes were ultrasonically dispersed in 100 mL of deionized water, and then 500 μL of 1% chloroauric acid solution and 24 mg of NaBH4 were sequentially added thereto under stirring, stirred at room temperature for 12 h, the product was collected by centrifugation and washed with water and ethanol for several times, and finally dried at 50°C under vacuum for 12 h to obtain Ti3C2-CNTs-Au.

[0038] (3) Preparation of CD-MOF-CNTs: To obtain CD-MOF-CNTs, 20 mg of acidified multi-walled carbon nanotubes were added to the supernatant after diffusion was completed, ultrasonically dispersed for 1 h, then CTAB was added and incubated for 3 h, and finally the precipitate was collected by centrifugation to obtain CD-MOF-CNTs.

[0039] (4) First, prepare dispersions of Ti3C2-CNTs-Au (2 mg / mL) and CD-MOF-CNTs (2 mg / mL) (dispersant: N,N-dimethylformamide) and ultrasonically disperse for 1 h. Next, take 12 μL of Ti3C2-CNTs-Au dispersion and 4 μL of CD-MOF-CNTs ultrasonic mixture for 30 min. Then, the mixed composite material is drop-coated on the surface of a clean glassy carbon electrode, dried under an infrared lamp and collected to obtain a modified electrode.

[0040] Example 2

[0041] The present application provides a preparation method of a high-sensitivity rutin electrochemical sensor of Ti3C2-CNTs-Au / CD-MOF-CNTs, comprising the following steps:

[0042] (1) Synthesis of multilayer Ti3C2 MXene: Multilayer Ti3C2 is produced by immersing Ti3AlC2 in HF at room temperature, and the aluminum element is selectively etched by HF. First, 1 gram of Ti3AlC2 is dispersed in 20 milliliters of HF and continuously stirred at room temperature for 30 hours. Next, the obtained product is washed several times with ultrapure water until the pH value of the supernatant reaches 5.5 to remove excess HF. Finally, the multilayer Ti3C2 is collected and dried.

[0043] (2) Preparation of Ti3C2-CNTs-Au: 25 mg of multilayer Ti3C2 MXene and 25 mg of acidified multi-walled carbon nanotubes were ultrasonically dispersed in 100 mL of deionized water, and then 500 μL of 1% chloroauric acid solution and 24 mg of NaBH4 were sequentially added thereto under stirring, stirred at room temperature for 12 h, the product was collected by centrifugation and washed with water and ethanol for several times, and finally dried at 50°C under vacuum for 12 h to obtain Ti3C2-CNTs-Au.

[0044] (3) Preparation of CD-MOF-CNTs: To obtain CD-MOF-CNTs, 20 mg of acidized multi-walled carbon nanotubes were added to the supernatant after diffusion was completed, ultrasonic dispersion was performed for 1 h, then CTAB was added and incubated for 2.5 h, and finally the precipitate was collected by centrifugation to obtain CD-MOF-CNTs.

[0045] (4) First, dispersions of Ti3C2-CNTs-Au (1 mg / mL) and CD-MOF-CNTs (1 mg / mL) were prepared (dispersant: N,N-dimethylformamide) and ultrasonic dispersion was performed for 1 h. Next, 8 μL of the Ti3C2-CNTs-Au dispersion and 4 μL of the CD-MOF-CNTs were mixed ultrasonically for 30 min. Then, the mixed composite material was drop-cast on the surface of a clean glassy carbon electrode, dried under an infrared lamp, and collected to obtain the modified electrode.

[0046] Example 3

[0047] The present application provides a preparation method of a high-sensitivity rutin electrochemical sensor of Ti3C2-CNTs-Au / CD-MOF-CNTs, comprising the following steps:

[0048] (1) Synthesis of multi-layer Ti3C2 MXene: Multi-layer Ti3C2 is produced by immersing Ti3AlC2 in HF at room temperature, and the aluminum element is selectively etched by HF. First, 1 gram of Ti3AlC2 was dispersed in 20 milliliters of HF and continuously stirred at room temperature for 36 hours. Next, the obtained product was washed several times with ultrapure water until the pH value of the supernatant reached 6.5 to remove excess HF. Finally, the multi-layer Ti3C2 was collected and dried.

[0049] (2) Preparation of Ti3C2-CNTs-Au: 25 mg of multi-layer Ti3C2 MXene and 25 mg of acidized multi-walled carbon nanotubes were ultrasonically dispersed in 100 mL of deionized water, then 500 μL of 1% chloroauric acid solution and 24 mg of NaBH4 were sequentially added thereto under stirring, stirred at room temperature for 12 h, the product was collected by centrifugation and washed with water and ethanol several times, and finally dried under vacuum at 50°C for 12 h to obtain Ti3C2-CNTs-Au.

[0050] (3) Preparation of CD-MOF-CNTs: To obtain CD-MOF-CNTs, 20 mg of acidized multi-walled carbon nanotubes were added to the supernatant after diffusion was completed, ultrasonic dispersion was performed for 1 h, then CTAB was added and incubated for 4 h, and finally the precipitate was collected by centrifugation to obtain CD-MOF-CNTs.

[0051] (4) First, the dispersions of Ti3C2-CNTs-Au (4 mg / mL) and CD-MOF-CNTs (4 mg / mL) were configured respectively (dispersant: N, N-dimethylformamide) and ultrasonically dispersed for 1 h. Next, 16 μL of Ti3C2-CNTs-Au dispersion and 4 μL of CD-MOF-CNTs were mixed ultrasonically for 30 min. Then, the mixed composite material was drop-coated on the surface of a clean glassy carbon electrode, dried under an infrared lamp, and the modified electrode was obtained.

[0052] The pretreatment of the glassy carbon electrode in Examples 1-3 produced a clean glassy carbon electrode surface: the glassy carbon electrode was polished with 0.05 μm Al2O3 powder, and then ultrasonically washed in ethanol and ultrapure water for 5 min each using an ultrasonic cleaner. Subsequently, a clean glassy carbon electrode was obtained by drying under an infrared lamp.

[0053] Comparative Example:

[0054] As a comparative example, CD-MOF-1 was used instead of CD-MOF-CNTs, and the synthesis of CD-MOF-1 was as follows: 3.24 g of γ-cyclodextrin and 1.12 g of KOH were added to 100 mL of water and ultrasonically dispersed and dissolved, filtered using a 0.45 μm filter membrane, and methanol was diffused into the filtrate by diffusion method for several days. After the diffusion was completed, the supernatant was collected, and 80 mg of cetyltrimethylammonium bromide (CTAB) was added, resulting in a large amount of precipitate, the suspension was incubated at room temperature for 3 h, the precipitate was collected, and washed with isopropanol 3 times, and vacuum dried at 50°C for 12 h to obtain monodisperse CD-MOF-1. Subsequently, a modified electrode was prepared with Ti3C2-CNTs-Au in the same way as Example 1.

[0055] Effect Example:

[0056] The electrocatalytic activity of Ti3C2-CNTs-Au / CD-MOF-CNTs nanocomposite was measured by cyclic voltammetry and electrochemical impedance spectroscopy, which showed that the electrochemical sensor had unique redox electrochemical catalytic activity and could be used for electrochemical detection of rutin. In a PBS electrolyte (pH = 6.0), a bare glassy carbon electrode or a modified glassy carbon electrode was used as the working electrode, a platinum electrode was used as the auxiliary electrode, and an Ag / AgCl electrode was used as the reference electrode. In a 5 mM [Fe(CN)6] 3- / 4- solution containing 0.1 M KCl, the EIS Nyquist plots of bare GCE, Ti3C2 / GCE, Ti3C2-CNTs-Au / GCE, CD-MOF-1 / GCE, CD-MOF-CNTs / GCE and Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE were obtained, and the impedance radius was observed.

[0057] The Ti3C2-CNTs-Au / CD-MOF-CNTs rutin electrochemical sensor was tested in the following environment: the Ti3C2-CNTs-Au / CD-MOF-CNTs modified electrode was used as the working electrode, the platinum wire electrode was used as the counter electrode, and the Ag / AgCl electrode was used as the reference electrode. The potential range was -0.1V to 0.8V, the scan amplitude was 50mV, the pulse width was 200ms, and the entire test was conducted in PBS buffer solution with pH=6.0.

[0058] Scanning electron micrographs of materials, such as Figures la-le As shown, Ti3C2 exhibits a classic accordion-like structure. Figure la CD-MOF-1 exhibits a uniform cubic structure. Figure lb This indicates that the synthesis of Ti3C2 and CD-MOF-1 was successful. Figure lc The results show that carbon nanotubes and Au have adhered to Ti3C2, indicating that Ti3C2-CNTs-Au has been successfully prepared. Similarly, Figure Id This indicates that the carbon nanotubes encapsulate CD-MOF-1 and are uniformly dispersed. After combining these two materials, CD-MOF-1 can be seen bound around Ti3C2-CNTs-Au, indicating that the composite process was successful and effective.

[0059] As attached Figure 2 The image shows the EIS Nyquist plots of bare GCE, Ti3C2 / GCE, Ti3C2-CNTs-Au / GCE, CD-MOF-1 / GCE, CD-MOF-CNTs / GCE, and Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE in a 5 mM [Fe(CN)6]3- / 4- solution containing 0.1 M KCl.

[0060] The impedance curve radius of the Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE is close to that of a straight line. In summary, the Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE electrochemical sensor exhibits strong electrocatalytic activity.

[0061] As attached Figure 3 The DPV plots of rutin at different concentrations on Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE in 0.1M PBS buffer (pH 6.0) show that the oxidation potential of rutin is between 0.20V and 0.50V. The response current on the electrode increases with increasing rutin concentration, with a detection limit of 0.6 nM.

[0062] As attached Figure 4The linear relationship between the concentration of rutin and the peak current is shown in the graph. As can be seen from the graph, in the concentration range of 2nM-800nM detected in the text, the concentration of rutin and the peak current showed a linear relationship, the linear curve was y1=0.10x-0.55, and the correlation coefficient R2=0.9928.

[0063] As shown in the accompanying Figure 5 The prepared Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE modified 8 glassy carbon electrodes were used to detect rutin, and the 8 electrodes were basically unbiased, indicating that the prepared Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE electrochemical sensor had good reproducibility.

[0064] As shown in the accompanying Figure 6 The repeatability test of a single electrode was carried out by DPV technology, and the peak current signal changed slightly after 10 repeated tests, indicating that the prepared Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE electrochemical sensor had good reproducibility.

[0065] As shown in the accompanying Figure 7 The test of a single electrode with different storage times (days) was carried out by DPV technology, and the peak current signal changed slightly on the modified electrodes stored in the refrigerator for 0, 4, 8, 12, 16 and 20 days, indicating that the prepared Ti3C2-CNTs-Au / CD-MOF-CNTs / GCE electrochemical sensor had good stability.

[0066] As shown in the accompanying Figure 8 As shown in the accompanying

[0067] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit the technical solutions. Those of ordinary skill in the art should understand that those who modify or equivalently replace the technical solutions of the present application without departing from the purpose and scope of the technical solutions should be covered in the scope of the claims of the present application.

Claims

1. A method for preparing a highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs, characterized in that, Includes the following steps: (1) Synthesis of multilayer Ti3C2MXene: Ti3AlC2 was dispersed in HF at room temperature, and the solid product obtained was washed with ultrapure water with continuous stirring until the pH value of the supernatant reached 5.5-6.

5. After drying, multilayer Ti3C2MXene was obtained. (2) Preparation of Ti3C2-CNTs-Au: The multilayer Ti3C2MXene and acidified multiwalled carbon nanotubes prepared in step (1) were dispersed in deionized water, and then chloroauric acid solution and NaBH4 were added to it in sequence under stirring. The product was collected by stirring and centrifugation at room temperature and washed with water and ethanol several times. Finally, it was dried to obtain Ti3C2-CNTs-Au. (3) Preparation of CD-MOF-CNTs: γ-cyclodextrin and KOH were added to water and dispersed and dissolved. The mixture was filtered through a filter membrane. Methanol was diffused into the filtrate by diffusion. After diffusion, the supernatant was collected and acidified multi-walled carbon nanotubes were added. After dispersion, hexadecyltrimethylammonium bromide was added and incubated. Finally, the precipitate was collected by centrifugation to obtain CD-MOF-CNTs. (4) Ti3C2-CNTs-Au and CD-MOF-CNTs were mixed with the dispersion liquid and dispersed to obtain the dispersion liquid. Next, Ti3C2-CNTs-Au dispersion liquid and CD-MOF-CNTs dispersion liquid were mixed to obtain the composite material. The mixed composite material was drop-coated on the surface of a clean glassy carbon electrode and dried to obtain the modified electrode.

2. The method for preparing the highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs according to claim 1, characterized in that, The dispersion in step (4) is N,N-dimethylformamide.

3. The method for preparing the highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs according to claim 1, characterized in that, In step (2), step (3) and step (4), dispersion is performed using ultrasound.

4. The method for preparing the highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs according to claim 1, characterized in that, The clean glassy carbon electrode surface in step (4) is achieved by the following method: polishing the glassy carbon electrode with Al2O3 powder, then ultrasonically cleaning the glassy carbon electrode in ethanol and ultrapure water respectively using an ultrasonic cleaner, and then drying it under an infrared lamp to obtain a clean glassy carbon electrode.

5. The method for preparing the highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs according to claim 1, characterized in that, The pH value of the supernatant in step (1) is 6.

6. The method for preparing the highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs according to claim 1, characterized in that, In step (4), the modified electrode is obtained by infrared drying.

7. The method for preparing the highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs according to claim 1, characterized in that, The incubation in step (3) is carried out at room temperature for 2.5-4 hours.

8. The method for preparing the highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs according to claim 1, characterized in that, In step (4), the concentrations of the dispersions of Ti3C2-CNTs-Au and CD-MOF-CNTs are both 1-4 mg / mL, and the volume ratio of Ti3C2-CNTs-Au dispersion to CD-MOF-CNTs dispersion is 2-4:

1.

9. A highly sensitive rutin electrochemical detection electrode based on Ti3C2-CNTs-Au / CD-MOF-CNTs, characterized in that, The electrode prepared by the method described in any one of claims 1-8 has a working electrode modified with Ti3C2-CNTs-Au / CD-MOF-CNTs, a counter electrode made of graphite or platinum wire, and a reference electrode made of Ag / AgCl. The potential range is 0.1V-0.8V, the scanning amplitude is 50mV, the pulse width is 200ms, and the environmental solution is a phosphate buffer solution with pH = 5.8-6.

2.

10. The application of the highly sensitive rutin electrochemical detection electrode according to claim 9 in measuring rutin concentration.

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