Preparation method of imprinted electrode for electric sensing targeted detection of clotetracycline

Abstract

The invention provides a preparation method of an imprinted electrode for electric sensing targeted detection of clotetracycline. The preparation method comprises the following steps: (1) preparation of V2CTx MXene, (2) synthesis of Au-PtRu NA, (3) preparation of Au-PtRu / V2CTx / GCE, and (4) preparation of an imprinted electrode (MIP / Au-PtRu / V2CTx / GCE). According to the preparation method of the imprinted electrode for the electric sensing targeted detection of the clotetracycline, V2CTx MXene and Au-PtRu NA which are modified on the surface of the electrode layer by layer serve as electric sensing sensitizing materials, the introduced V2CTx MXene increases the specific surface area of an electrode interface, more binding sites are provided for the post-modified Au-PtRu NA, and due to introduction of the Au-PtRu NA, the specific surface area of the electrode interface is increased while V2CTx MXene sheet layer stacking is avoided, and the specific surface area of the electrode interface is increased. On the basis, the molecularly imprinted electrode which is high in sensitivity, high in selectivity, accurate and convenient to measure the chlorotetracycline (CTC) is prepared by combining a molecularly imprinted technology.

Description

Technical Field

[0001] The present invention belongs to the field of electrochemistry, and particularly relates to a preparation method of an electro-sensing targeted detection chlorotetracycline imprinted electrode. Background Art

[0002] Tetracyclines (TCs) are a class of antibiotics widely used in the treatment of various bacterial infections caused by Gram-positive / negative bacteria, rickettsia, mycoplasma, chlamydia, protozoa, and parasites. As one of the typical representatives, chlorotetracycline (CTC) not only has good broad-spectrum antibacterial activity but also can promote the growth of livestock. Due to its significant therapeutic effect and low cost, CTC has been widely used in many fields such as animal husbandry and aquaculture. However, the improper use of CTC will lead to its residues in the environment and food chain, which will pose potential hazards to human health after accumulation. Therefore, it is crucial to establish highly sensitive, highly selective, accurate, and convenient CTC analysis techniques and methods.

[0003] Two-dimensional (2D) transition metal carbides and nitrides (MXene) have received extensive attention in the fields of energy storage and conversion, environmental remediation, and sensing due to their large specific surface area, atomic-level thickness, excellent electrical properties, and rich surface chemistry. V2CT x As a member of the MXene material, it not only inherits the above advantages but also has a lower theoretical resistance compared with other MXene materials and is an excellent electrode modification material. In order to further improve the performance of V2CT x MXene and avoid problems such as sheet stacking, overlapping, and collapse, the combination / integration of V2CT x MXene with various noble metal-based conductive materials has become a current research hotspot. As a noble metal-based conductive material, noble metal nanoalloys (NA) have better performance than single-component nanomaterials due to their synergistic effects. Among all platinum group noble metals, PtRu NA has enhanced electrical properties and excellent surface activity. The alloying of Pt and Ru is beneficial to changing the electronic structure of Pt and significantly improving the sensing ability. At the same time, introducing relatively low-cost Ru can minimize the use of Pt while maintaining high activity. In addition, in order to improve the post-modifiability of the electrode interface, introducing gold (Au) components into PtRu NA is also essential because it has good biocompatibility and the introduced Au at the atomic level can further enhance the long-term stability of NA.

[0004] Molecular imprinting technology (MIT) is a technology that mimics the biological recognition process. The prepared molecularly imprinted polymers (MIPs) are called "artificial antibodies / receptors". It can obtain specific recognition ability according to different template molecules. The prepared MIP membrane has a specific spatial structure and recognition sites, and can selectively recognize target molecules. However, modifying the non-conductive MIP membrane alone on the electrode surface will affect the transmission of electrochemical signals, resulting in a decrease in detection sensitivity, and the exposed binding sites show uneven distribution, reducing the targeted recognition. Summary of the Invention

[0005] In view of this, the present invention aims to overcome the defects in the prior art and proposes a preparation method of an electro-sensing targeted detection chlorotetracycline imprinted electrode.

[0006] To achieve the above object, the technical solution of the present invention is realized as follows: The present invention provides a preparation method of an electro-sensing targeted detection chlorotetracycline imprinted electrode, including the following steps: Step 1 is to slowly immerse V2AlC into the etching agent, stir, wash, and centrifuge, collect the precipitate, and dry the precipitate to obtain V2CT x MXene nanomaterial; Step 2 is to add an auxiliary agent to an organic solvent containing a surfactant, stir and sonicate, then add a Pt-containing solution and a Ru-containing solution thereto, stir, then add an Au-containing solution thereto, stir, and then dropwise add a reducing agent. After the reaction is completed, age at room temperature. Wash and centrifuge the obtained mixture to obtain Au-PtRu NA; Step 3 is to disperse the V2CT x MXene in an alcohol solution, drop the obtained suspension onto the surface of GCE to obtain V2CT x / GCE. Prepare the Au-PtRu NA into an Au-PtRu NA-alcohol suspension, coat the Au-PtRu NA-alcohol suspension on the V2CT x / GCE surface, and evaporate the solvent to obtain Au-PtRu / V2CT x / GCE; Step 4 is to use CTC as a template molecule and oPD as a functional monomer, and prepare a MIP membrane precursor on the surface of the Au-PtRu / V2CT x / GCE electrode by the method of CV electro-polymerization. Immerse the precursor in the eluent, stir to remove the template molecule, wash and dry to obtain the imprinted electrode (MIP / Au-PtRu / V2CT x / GCE).

[0007] Further, the solid-liquid ratio of V2AlC to the etchant in Step 1 is 0.025 - 0.25 g: 1 mL; the etchant is an HF solution, and the mass concentration of HF is 30 - 70%.

[0008] Further, the stirring step in Step 1 is magnetic stirring for 1 - 7 days; the rotation speed of the centrifugation step in Step 1 is 2000 - 5000 rpm for 2 - 10 min.

[0009] Further, the solid-liquid ratio of the auxiliary agent, the organic solvent containing surfactant, the Pt-containing solution, the Ru-containing solution, the Au-containing solution, and the reducing agent in Step 2 is 0.01 - 0.1 g: 1 - 10 mL: 50 - 200 μL: 50 - 200 μL: 25 - 100 μL: 50 - 200 μL.

[0010] Further, the auxiliary agent is 1-adamantanecarboxylic acid; the Pt-containing solution is an H2PtCl6 solution with a concentration of 0.1 - 0.5 M; the Ru-containing solution is an RuCl3 solution with a concentration of 0.1 - 0.5 M; the Au-containing solution is an HAuCl4 solution with a concentration of 0.1 - 0.5 M; the reducing agent is a KBH4 solution with a concentration of 0.01 - 0.5 g•mL -1 ; the organic solvent containing surfactant in Step 2 is a polyvinylpyrrolidone-N,N-dimethylacetamide mixed solution with a concentration of 0.01 - 0.1 g•mL -1 .

[0011] Further, the time of the ultrasonic step in Step 2 is 0.5 - 10 min; the reaction time in Step 2 is 0.5 - 3 h; the aging time in Step 2 is 6 - 24 h; the rotation speed of the centrifugation step in Step 2 is 5000 - 12000 r•min -1 , and the time is 3 - 10 min.

[0012] Further, the mass ratio of V2CT x Mxene to Au-PtRu NA in Step 3 is 0.1 - 1:1.

[0013] Further, the molar ratio of CTC to oPD in Step 4 is 0.1 - 1:1; the eluent in Step 4 is a methanol-acetic acid eluent; the volume ratio of methanol to acetic acid in the methanol-acetic acid eluent is 1 - 19:1.

[0014] The described V2CT x MXene has a multi-layer flaky structure with a specific surface area of 5 - 50 m 2 •g -1 , an average pore diameter of 2 - 5 nm, and a pore volume of 0.01 - 0.05 cm 3 •g -1 ; Au - PtRu NA has a network structure with a particle size of 5 - 20 nm; the constructed Au - PtRu / V2CT x / GCE has enhanced electro - sensing signal; the imprinted electrode (MIP / Au - PtRu / V2CT x / GCE) has the ability to target - recognize CTC.

[0015] The present invention also provides an electro - sensing targeted detection of chlortetracycline imprinted electrode prepared by using the described preparation method.

[0016] The present invention also provides an application of the electro - sensing targeted detection of chlortetracycline imprinted electrode, and the application of the electrode in detecting animal - derived foods.

[0017] Compared with the prior art, the present invention has the following advantages: The preparation method of the electro - sensing targeted detection of chlortetracycline imprinted electrode according to the present invention uses the V2CT x MXene and Au - PtRu NA layer - by - layer modified on the electrode surface as electro - sensing sensitizing materials. The introduced V2CT x MXene increases the specific surface area of the electrode interface and provides more binding sites for the subsequently modified Au - PtRu NA. The introduction of Au - PtRu NA avoids the stacking of V2CT x MXene sheets while realizing the sensitization of the electro - sensing signal. On this basis, combined with the molecular imprinting technology, an imprinted electrode (MIP / Au - PtRu / V2CT x / GCE) with high sensitivity, high selectivity, accuracy, and convenience for CTC determination is prepared.

[0018] The MIP / Au - PtRu / V2CT x / GCE imprinted electrode according to the present invention respectively prepares multi - layer flaky V2CT x MXene with abundant mesopores and network - structured Au - PtRu NA through acid etching technology and one - step reduction method. After layer - by - layer modification on the GCE surface, the electro - sensing signal is amplified and the electro - sensing performance of the electrode is enhanced. Then, through the method of CV electro - polymerization on Au - PtRu / V2CT xMIPs with high targeting and good stability were synthesized on the / GCE surface, enabling highly sensitive and specific determination of CTC. Compared with the existing methods of large instrument analysis (HPLC and LC-MS), this method has the advantages of high sensitivity, strong selectivity, and simple sample pretreatment. Brief Description of the Drawings

[0019] Figure 1 V2AlC MAX and V2CT described in the embodiments of the present invention x Scanning electron microscope images and elemental mapping images of MXene: Among them, Figure A is 10 μm, Figure B is 1 μm, Figure C is 5 μm, Figure D is 1 μm, Figures a - d are the mapping images of Figure B, and Figures e - h are the mapping images of Figure D; Figure 2 V2CT described in the embodiments of the present invention x Transmission electron microscope images of MXene: Among them, Figure A is 100 nm, Figure B is 50 nm, Figure C is 10 nm, and Figure D is 5 nm; Figure 3 V2CT described in the embodiments of the present invention x N2 adsorption - desorption isotherm and pore size distribution diagram of MXene; Figure 4 Transmission electron microscope images of Au - PtRu NA described in the embodiments of the present invention: Among them, Figure A is 20 nm, Figure B is 100 nm, Figure C is 10 nm, Figure D is 5 nm, Figure E is 5 nm, Figures a - c are the mapping images of Figure B, Figure d is the SAED image of Figure C, Figures e - f are the enlarged images of Figure D, and Figure g is the enlarged image of Figure E; Figure 5 Au - PtRu / V2CT described in the embodiments of the present invention x CV diagram of / GCE; Figure 6 Au - PtRu / V2CT described in the embodiments of the present invention x EIS diagram of / GCE; Figure 7 MIP / Au - PtRu / V2CT described in the embodiments of the present invention x / GCE and NIP / Au - PtRu / V2CT x / GCE and MIP / Au - PtRu / V2CT x CV diagram of the re - adsorption of / GCE; Figure 8 MIP / Au - PtRu / V2CT described in the embodiments of the present invention x / GCE and NIP / Au - PtRu / V2CTx / GCE and MIP / Au-PtRu / V2CT x EIS diagram of re-adsorption on / GCE; Figure 9 MIP / Au-PtRu / V2CT described in the embodiment of the present invention x Elution kinetic curve of / GCE; Figure 10 MIP / Au-PtRu / V2CT described in the embodiment of the present invention x Adsorption kinetic curve of / GCE; Figure 11 MIP / Au-PtRu / V2CT described in the embodiment of the present invention x Response curve of / GCE to CTC with different concentrations; Figure 12 MIP / Au-PtRu / V2CT described in the embodiment of the present invention x Linear relationship diagram of / GCE to CTC with different concentrations; Figure 13 MIP / Au-PtRu / V2CT described in the embodiment of the present invention x Selectivity experiment diagram of / GCE to organic interferents; Figure 14 MIP / Au-PtRu / V2CT described in the embodiment of the present invention x Selectivity experiment diagram of / GCE to interfering ions. Detailed implementation manners

[0020] Unless otherwise defined, the technical terms used in the following embodiments have the same meaning as commonly understood by those skilled in the art to which the present invention belongs. The test reagents used in the following embodiments are all conventional biochemical reagents unless otherwise specified; the experimental methods are all conventional methods unless otherwise specified.

[0021] The present invention will be described in detail below with reference to the embodiments.

[0022] Example 1

[0023] A preparation method of an electro-sensing targeted detection tetracycline hydrochloride imprinted electrode includes the following steps: (1) Weigh 1.5 g of V2AlC powder, slowly immerse it in 20 mL of HF, and magnetically stir for 7 days at room temperature. Then wash it with deionized water and centrifuge at 3500 rpm for 4 min until the pH of the supernatant is close to 7. Finally, collect the obtained precipitate and dry it overnight under vacuum conditions to obtain V2CT x Mxene; (2) Prepare a polyvinylpyrrolidone-N,N-dimethylacetamide (PVP-DMAC) mixed solution with a concentration of 0.02 g•mL -1 . Then add 0.05 g of 1-adamantanecarboxylic acid (ACA) to the above 5 mL of the mixed solution, stir magnetically for 5 min, and after ultrasonic oscillation for 2 min, add 150 μL of H2PtCl6 solution (0.15 M) and 150 μL of RuCl3 solution (0.15 M) in sequence. After magnetic stirring for 10 min, add 50 μL of HAuCl4 solution (0.15 M) dropwise to the above mixed system. Measure 150 µL of the pre-prepared aqueous KBH4 solution (0.1 g•mL -1 ) and slowly add it dropwise. The color of the system turns black. After magnetic stirring for 1 h, stop the reaction and age it for 24 h at room temperature. Wash the obtained mixture 4 times with absolute ethanol and centrifuge (8000r•min -1 ) for 5 min to obtain Au-PtRu NA; (3) Disperse the V2CT x MXene (40 mg) prepared in step (1) in 10 mL of ethanol-aqueous solution (v:v = 1:1), and drop 10 μL of the suspension onto the surface of the GCE to obtain V2CT x / GCE. Prepare an Au-PtRu NA-ethanol suspension with the Au-PtRu NA prepared in step (2) at a concentration of 8mg•mL -1 . Measure 15 μL and coat it on the surface of V2CT x / GCE. After solvent evaporation, obtain Au-PtRu / V2CT x / GCE; (4) Using CTC (2 mM) as the template molecule and oPD (10 mM) as the functional monomer, prepare a MIP film precursor on the surface of the electrode prepared in step (3) by cyclic voltammetry (CV) method (potential range: 0 - 0.8 V, number of cycles: 8 times, scan rate: 50 mV•s -1 ) in acetic acid buffer solution (pH = 5.4). Then immerse the electrode in a methanol-acetic acid (v:v = 95:5) eluent and stir magnetically for 12 min to remove the template molecule. After washing and drying with deionized water, obtain the imprinted electrode (MIP / Au-PtRu / V2CT x / GCE).

[0024] The synthesized V2CT x MXene was characterized by scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption isotherm and pore size distribution, and the transmission electron microscopy of Au-PtRu NA was also carried out.

[0025] The prepared V2CT x The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images of MXene are shown as Figure 1-2 follows. It can be seen from the figures that the prepared material exhibits a multi-layered flake structure, such as a "wet book board", which is significantly different from the morphology of the precursor V2AlC MAX. Through Al element mapping analysis, it is known that the formed "wet book board" structure is obtained by selectively stripping the Al element by acid etching. At the same time Figure 2 a bundle of layered nanosheet structures can also be clearly observed, which is attributed to the unique characteristics of V2CT x MXene. The existence of the layered structure further confirms the successful synthesis of two-dimensional MXene materials.

[0026] Figure 3 This is the N2 adsorption-desorption isotherm and pore size distribution diagram of V2CT x MXene described in the embodiment of the present invention. The specific surface area of V2CT x MXene calculated by the BET method is 10.3 m 2 •g -1 -1, and the average pore diameter calculated by the BJH method is 3.65 nm, and the pore volume is 0.029 cm 3 •g -1 -1. This result confirms the existence of mesopores. The mesoporous structure can enhance the modifiability of the active region and provide a favorable microenvironment for electrochemical reactions.

[0027] Figure 4 This is the TEM image of Au-PtRu NA described in the embodiment of the present invention. The synthesized Au-PtRu NA has good dispersibility and a network structure. At the same time, the mapping images of Au, Pt, and Ru elements (as shown in Figure 4 Figures a-c in) confirm that the three elements are evenly distributed. Figure 4 The four diffraction rings presented in Figure d in belong to the (111), (200), (220), and (311) crystal planes of Au-PtRu NA in turn, indicating that it has a random and independent growth direction. After magnification, the lattice spacing of Au-PtRu NA is measured to be 0.225 nm (see Figure 4 Figure e in), which is consistent with the lattice spacing of the (111) crystal plane. In addition, the surface defects of Au-PtRu NA, such as stacking faults, dislocations, and interstitial defects in Figure 4 Figure f, and twin boundaries in Figure 4 Figure g, indicate that the surface of Au-PtRu NA has high active centers, which not only facilitate the post-modification of the electrode but also improve the electrochemical sensing ability.

[0028] Example 2

[0029] Study on the Sensitization Performance of Au - PtRu / V2CT x / GCE. As Figure 5 shown, the CV curves of different modified electrodes were measured in a 0.1 M KCl solution containing 1.0 mM [Fe(CN)6] 3- / 4- . All the electrodes presented a pair of typical redox characteristic peaks. The order of the anodic peak current was as follows: Au - PtRu / V2CT x / GCE > Au - PtRu / GCE > V2CT x / Au - PtRu / GCE > bare GCE > V2CT x / GCE. Among them, the GCE modified with the Au - PtRu / V2CT x nanocomposite showed the highest current response, which was based on the synergistic effect of Au - PtRu NA and V2CT x MXene. On the one hand, the unique layered structure of V2CT x MXene had a large specific surface area, which could provide a large number of anchoring sites for Au - PtRu NA. On the other hand, the post - modified Au - PtRu NA had high conductivity, which was attributed to its unique physical and chemical properties and alloy effect. To evaluate the charge transfer resistance (R ct ) of the modified electrodes, EIS experiments were carried out in a 0.1 M KCl solution containing 5.0 mM [Fe(CN)6] 3- / 4- . As Figure 6 shown, in the Nyquist plot, the bare GCE showed a semicircle in the high - frequency region, and the R ct value fitted according to the equivalent circuit was 233.2 Ω (see the inset). When V2CT x MXene was modified on the surface of the bare GCE and Au - PtRu / GCE, the obtained R ct values were 302.4 Ω and 98.4 Ω respectively. For the modification of Au - PtRu NA, the corresponding Nyquist plot presented a straight line, which was attributed to the dominant diffusion process. In addition, after the Au - PtRu / V2CT x nanocomposite was modified on the surface of the GCE, the semicircle in the high - frequency region disappeared, which was similar to the EIS curve of Au - PtRu / GCE. This indicated that the introduced highly conductive nanocomposite could effectively improve the charge transfer kinetics at the electrode / solution interface.

[0030] Example 3

[0031] Study on the imprinted electrode (MIP / Au - PtRu / V2CT x / GCE) and the non - imprinted electrode (NIP / Au - PtRu / V2CT xThe electrochemical performance of (MIP / Au-PtRu / V2CT Figure 7 The CV curves of the imprinted electrode and non-imprinted electrode before and after elution and the re-adsorption of CTC by the imprinted electrode are shown. In curves a and b, no redox peaks appear on the imprinted electrode and non-imprinted electrode before elution, indicating that the polymer film with non-conductive properties covers the electrode surface well. After elution with methanol-acetic acid (v:v = 95:5), obvious redox peak currents appear on the imprinted electrode (curve c), indicating that the template molecule (CTC) is successfully removed. The current response of the non-imprinted electrode (curve d) changes little. This slight change may be due to the formation of some cracks on the electrode surface during the elution process. When 150 μM CTC is re-adsorbed, the current response of the imprinted electrode (curve e) decreases significantly, which is because the formed imprinted cavity is occupied by CTC molecules again, hindering the transfer of electrons from the probe to the electrode interface. As Figure 8 shown, the EIS technique provides information on the change in charge transfer resistance at the electrode / electrolyte interface. According to the equivalent circuit embedded in the figure, the R ct values of the imprinted electrode before and after elution and after re-adsorption are 3284 Ω (curve a), 685.7 Ω (curve c), and 1400 Ω (curve e), respectively. The above results indicate that the prepared MIP film generates abundant imprinted cavities complementary to the template molecule and can target and recognize CTC. For the non-imprinted electrode before and after elution, the corresponding R ct values are 3358 Ω (curve b) and 3247 Ω (curve d), respectively, indicating that the NIP film without introducing the template molecule (CTC) does not form imprinted cavities, inhibits the diffusion and reaction of the probe, and thus has no targeting recognition ability for CTC molecules. In addition, the obtained EIS results are also consistent with the CV results, further confirming the successful preparation of the imprinted electrode (MIP / Au-PtRu / V2CT x / GCE).

[0032] Example 4

[0033] Study the elution and adsorption performance of the imprinted electrode (MIP / Au-PtRu / V2CT x / GCE). It can be seen that as the elution time increases, the DPV peak current value gradually increases and reaches the maximum value at 12 min, indicating that the template molecule (CTC) is well removed, and the formed imprinted cavity provides the maximum channel for the probe ions. Then, an adsorption experiment evaluation was carried out in a CTC solution containing 150 μM. As Figure 9 shown, as the adsorption time increases, the DPV current response value gradually decreases and reaches the adsorption equilibrium after 7 min, indicating that the imprinted cavity on the surface of the imprinted electrode is embedded with the template molecule and reaches the state of adsorption saturation. Figure 10

[0034] Example 5

[0035] Study the analytical performance of the imprinted electrode (MIP / Au-PtRu / V2CT x / GCE) for different concentrations of CTC. The DPV current response of the prepared imprinted electrode at CTC concentrations of 1 - 120 μM was measured using the [Fe(CN)6] 3- / 4- probe. As can be seen, under the optimal experimental conditions, as the CTC concentration increases, the obtained current response gradually decreases, indicating that the exposed imprinted cavity is occupied by CTC molecules, inhibiting the electron transfer process. At the same time, as Figure 11 shown, within the range of 1 - 120 μM, there is a good linear relationship between the CTC concentration and the difference in the response current. Figure 12

[0036] Example 6

[0037] Study the target adsorption performance of the imprinted electrode (MIP / Au-PtRu / V2CT x / GCE) for CTC. Tobramycin (TOB), doxycycline (DOX), ampicillin (AMP), chloramphenicol (CAP), hygromycin B (HYG), bisphenol A (BPA) at twice the CTC concentration and K + , Na + , Ca 2+ , Mg 2+ , Zn 2+ , Cu 2+ , Ni 2+ , Cd 2+ , Pb 2+ , Cl - , SO4 2- , NO3 - were selected as interfering substances. As Figure 13 and 14 shown, the ratio of the response signals (Δ I m / Δ I 0 ) with / without interfering substances ranges from 98.4% - 112.0%. The above results indicate that the MIP film formed after electro-polymerization and template molecule elution generates an imprinted cavity that can match the spatial structure of CTC, improving the target recognition ability of the imprinted electrode.

[0038] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.​

Claims

1. A method for preparing an electrosensing targeted detection chlortetracycline imprinted electrode, characterized in that: The steps include: Step 1 is to slowly immerse V2AlC into an etchant, stir, wash, centrifuge, collect the precipitate, and dry the precipitate to obtain V2CT. x MXene nanomaterials; Step 2 is to add the auxiliary agent to an organic solvent containing a surfactant, add a Pt solution and a Ru solution thereto after stirring and ultrasonication, add an Au solution thereto after stirring, dropwise add a reducing agent thereto after stirring, age at room temperature after the reaction is completed, wash the obtained mixture, centrifuge and obtain Au-PtRu NA; Step 3 is to convert the V2CT x MXene was dispersed in an alcohol solution, and the resulting suspension was dropwise applied to the GCE surface to obtain V2CT x / GCE, prepare the Au-PtRu NA into an Au-PtRu NA-alcohol suspension, and coat the Au-PtRu NA-alcohol suspension on V2CT x / GCE surface, and the solvent was evaporated to obtain Au-PtRu / V2CT x / GCE; Step 4 is to use CTC as a template molecule and oPD as a functional monomer in the Au-PtRu / V2CT x The MIP membrane precursor is prepared by CV electropolymerization on the surface of the Au / GCE electrode, and the precursor is immersed in an eluent, stirred to remove the template molecules, and washed and dried to obtain an imprinted electrode MIP / Au-PtRu / V2CT x / GCE.

2. The method for preparing the chlortetracycline imprinted electrode for electrical sensing targeted detection according to claim 1, characterized in that: The solid-to-liquid ratio of V2AlC to the etchant in step 1 is 0.025-0.25 g:1 mL; the etchant is HF solution, and the mass concentration of HF is 30-70%.

3. The method for preparing the chlortetracycline imprinted electrode for electrical sensing targeted detection according to claim 2, characterized in that: The stirring step in step 1 is magnetic stirring, and the time is 1-7 days; the rotation speed of the centrifugation step in step 1 is 2000-5000 rpm, and the time is 2-10 min.

4. The method for preparing the chlortetracycline imprinted electrode for electrical sensing targeted detection according to claim 1, characterized in that: The solid-liquid ratio of the auxiliary agent, the organic solvent containing a surfactant, the Pt solution, the Ru solution, the Au solution and the reducing agent in the step 2 is 0.01-0.1 g: 1-10 mL: 50-200 μL: 50-200 μL: 25-100 μL: 50-200 μL.

5. The method for preparing the chlortetracycline imprinted electrode for electrical sensing targeted detection according to claim 4, characterized in that: The auxiliary agent is 1-adamantanic acid; the Pt-containing solution is H2PtCl6 solution, and the concentration of the H2PtCl6 solution is 0.1-0.5 M; the Ru-containing solution is RuCl3 solution, and the concentration of the RuCl3 solution is 0.1-0.5 M; the Au-containing solution is HAuCl4 solution, and the concentration of the HAuCl4 solution is 0.1-0.5 M; the reducing agent is KBH4 solution, and the concentration of the KBH4 solution is 0.01-0.5 g•mL -1 The organic solvent containing a surfactant in step 2 is a polyvinyl pyrrolidone-N, N-dimethylacetamide mixed solution, and the concentration of the polyvinyl pyrrolidone-N, N-dimethylacetamide mixed solution is 0.01-0.1 g • mL -1 .

6. The method for preparing the chlortetracycline imprinted electrode for electrical sensing targeted detection according to claim 1, characterized in that: The duration of the ultrasonic step in step 2 is 0.5-10 min; the duration of the reaction in step 2 is 0.5-3 h; the duration of the aging step in step 2 is 6-24 h; the speed of the centrifugation step in step 2 is 5000-12000 r•min -1 , time is 3-10 min.

7. The method for preparing the chlortetracycline imprinted electrode for electrical sensing targeted detection according to claim 1, characterized in that: V2CT in step 3 x The mass ratio of Mxene to Au-PtRu NA is 0.1-1:

1.

8. The method for preparing the chlortetracycline imprinted electrode for electrical sensing targeted detection according to claim 1, characterized in that: The molar ratio of CTC to oPD in step 4 is 0.1-1:1; the eluent in step 4 is a methanol-acetic acid eluent; the volume ratio of methanol to acetic acid in the methanol-acetic acid eluent is 1-19:

1.

9. An electrical sensing targeted detection chlortetracycline imprinted electrode prepared by the preparation method according to any one of claims 1 to 8.

10. The use of the chlortetracycline imprinted electrode for electrical sensing targeted detection according to claim 9, characterized in that: The electrode is used in detecting animal-derived food.

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