An imprinted electrochemical sensor for detecting chlorpromazine and its preparation method

Abstract

The present invention discloses an imprinted electrochemical sensor for detecting chlorpromazine and a preparation method thereof. A saturated calomel electrode is used as a reference electrode, a platinum wire electrode is used as a counter electrode, and a stainless-steel acupuncture needle is used as a working electrode. Using the stainless-steel acupuncture needle as a substrate, copper and gold nanoparticles are sequentially modified on the surface of its tip through electrodeposition of metals to obtain an Au / Cu / ANE electrode. The electrode is immersed in a polymerization solution containing 3-aminophenylboronic acid and chlorpromazine, and an imprinted polymer film is formed by cyclic voltammetry electro-polymerization. Finally, the chlorpromazine molecules in the polymer film on the electrode surface are extracted by an eluent, so that an imprinted cavity capable of specifically recognizing chlorpromazine molecules is formed on the polymer film. The sensor prepared by the present invention can quickly detect the content of chlorpromazine in a solution, and the polymer film on the sensor surface can provide numerous imprinted sites for the oxidation of chlorpromazine. Moreover, it has strong anti-interference ability, high sensitivity, high stability, low cost, and simple preparation process.

Description

Technical Field

[0001] The present invention belongs to the field of electrochemical sensors, and specifically relates to an imprinted electrochemical sensor for detecting chlorpromazine and a preparation method thereof. Background Art

[0002] Chlorpromazine is a derivative of phenothiazine and is usually used to treat various mental diseases such as schizophrenia and mania. Like other drugs, chlorpromazine can also cause side effects. Excessive intake of chlorpromazine can lead to diseases such as epilepsy, abnormal heart rate, and Parkinson's disease, and long-term use can also cause liver damage. Therefore, the sensitive detection of chlorpromazine is of great significance.

[0003] Currently, the methods for detecting chlorpromazine mainly include high-performance liquid chromatography, liquid chromatography-mass spectrometry, spectrophotometry, etc. These detection methods are efficient and accurate, but have the disadvantages of high instrument operation cost, large and inconveniently portable equipment, and difficulty in real-time monitoring. Electrochemical methods have attracted much research attention due to their advantages of easy operation, low cost, simple preparation process, and rapid detection.

[0004] In addition, in human serum, coexisting substances may affect the detection of chlorpromazine. To improve selectivity, a recognition element is needed, and molecularly imprinted polymers are excellent candidate materials, which can provide electrochemical sensors with specific recognition properties. Molecular imprinting technology is to polymerize a template molecule with a suitable functional monomer to form a polymer, and then remove the template molecule encapsulated therein with an eluent, leaving a cavity that matches the structure of the template molecule. Currently, molecular imprinting technology has been widely used in the preparation process of electrochemical sensors, and the selectivity of the sensor for chlorpromazine can be improved through this technology. Summary of the Invention

[0005] An object of the present invention is to provide a preparation method of an imprinted electrochemical sensor for detecting chlorpromazine in view of the deficiencies of the prior art, using a saturated calomel electrode as the reference electrode, a platinum wire electrode as the counter electrode, and a stainless-steel acupuncture needle as the working electrode. The sensor can rapidly detect the content of chlorpromazine in a solution, and the polymer film on its surface can provide numerous imprinting sites for the oxidation of chlorpromazine. And the sensor has the advantages of strong anti-interference ability, high sensitivity, high stability, low cost, and simple preparation process.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] The imprinted electrochemical sensor uses a saturated calomel electrode as the reference electrode, a platinum wire electrode as the counter electrode, and the imprinted working electrode as the working electrode; it is characterized in that the imprinted working electrode is prepared by the following steps:

[0008] Step (1), pretreatment of the stainless-steel acupuncture needle;

[0009] After polishing the tip of the stainless-steel acupuncture needle with metallographic sandpaper, the polished part was ultrasonically cleaned successively with ethanol and deionized water, and then dried with nitrogen for standby.

[0010] Step (2), modification of nano-copper;

[0011] The tip part of the acupuncture needle electrode was immersed in an aqueous CuSO4 solution, and metallic Cu was deposited by cyclic voltammetry to obtain the electrode Cu / ANE; the voltage range of cyclic voltammetry was -1.0 V to -0.2 V; the number of deposition cycles was 5, and the deposition rate was 50 mV / s;

[0012] Step (3), modification of nano-gold;

[0013] The acupuncture needle electrode was immersed in an aqueous HAuCl4 solution, and metallic Au was deposited by cyclic voltammetry to obtain the electrode Au / Cu / ANE; the voltage range of cyclic voltammetry was -1.5 V to 0.5 V; the number of deposition cycles was 5, and the deposition rate was 25 mV / s.

[0014] Step (4), modification of the imprinted polymer membrane;

[0015] The acupuncture needle electrode was immersed in a phosphate buffer solution containing the monomer 3-aminophenylboronic acid and the template molecule chlorpromazine, and a molecularly imprinted polymer membrane was electro-polymerized on the surface of the acupuncture needle by cyclic voltammetry; the molar ratio of 3-aminophenylboronic acid to chlorpromazine was 1:1 to 1:5, and the voltage range of cyclic voltammetry was -0.2 V to 1.0 V; the number of deposition cycles was 20, and the deposition rate was 100 mV / s.

[0016] Step (5), elution of the template molecule

[0017] The prepared electrode was immersed in an eluent to remove the chlorpromazine molecules embedded in the imprinted membrane, and the final imprinted electrode was obtained.

[0018] Preferably, the concentration of the aqueous CuSO4 solution in step (2) is 5 mmol / L.

[0019] Preferably, the concentration of the aqueous HAuCl4 solution in step (3) is 8 mmol / L.

[0020] Preferably, the pH value of the buffer solution in step (4) is 5.0 to 9.0.

[0021] Preferably, the eluent in step (4) is a solution with a volume ratio of methanol:acetic acid of 9:1.

[0022] Another object of the present invention is to provide an imprinted electrochemical sensor for detecting chlorpromazine, an imprinted electrochemical sensor for detecting chlorpromazine, using a saturated calomel electrode as a reference electrode, a platinum wire electrode as a counter electrode, and an imprinted working electrode prepared by the method of any one of claims 1 to 4 as a working electrode.

[0023] Using stainless steel acupuncture needles as substrates, the needle tips were sequentially modified with copper and gold nanoparticles via electrodeposition. The electrodes were then immersed in a polymerization solution containing the monomer 3-aminophenylboronic acid and the template molecule chlorpromazine, where cyclic voltammetry was used to form an imprinted polymer film. Finally, the chlorpromazine molecules within the polymer film on the electrode surface were extracted using a 9:1 methanol:acetic acid mixture as an eluent, resulting in the formation of imprinted cavities on the polymer film that specifically recognize chlorpromazine molecules. This resulted in an imprinted electrochemical sensor capable of detecting chlorpromazine.

[0024] The beneficial effects of the present invention are as follows:

[0025] 1) This invention uses 3-aminophenylboronic acid as a monomer, leveraging the boronic acid groups in its structure to covalently bond with chlorpromazine molecules. Electropolymerization is then performed by immersing an electrode in a mixed solution of 3-aminophenylboronic acid and chlorpromazine to form a molecularly imprinted polymer film. After elution, the electrode is provided with imprinted sites that specifically recognize chlorpromazine molecules. The adsorption of chlorpromazine molecules by the boronic acid groups enables a rapid response of the electrode to chlorpromazine molecules. This sensor exhibits strong anti-interference capabilities, high sensitivity, and excellent stability.

[0026] 2) The present invention utilizes a suitable scan rate during copper deposition, which facilitates copper deposition on the surface of the acupuncture needle electrode. This results in a more uniform and dense copper distribution, forming a popcorn-like structure. This provides more contact area for subsequent gold deposition, resulting in a dendritic structure for the gold nanoparticles. This composite metal structure increases the surface area of the imprinted electrode where the metal layer contacts the chlorpromazine molecules after elution to form a cavity, enhancing the efficiency of electron transfer between the chlorpromazine molecules and the electrode, effectively improving the electrode's electrocatalytic performance.

[0027] 3) The present invention uses stainless steel acupuncture needles as the sensor substrate, which is small in size, low in cost and simple in preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 These are the performance curves of the electrochemical sensors prepared under different conditions in Examples 1 to 4, where A is the electrochemical performance curve under different molar ratios of the template molecule chlorpromazine to the monomer 3-aminophenylboronic acid, B is the electrochemical performance curve under different pH values of the polymerization solution, C is the electrochemical performance curve under different scan rates during electropolymerization, and D is the electrochemical performance curve under different numbers of electropolymerization cycles during electropolymerization.

[0029] Figure 2 Differential pulse response curves of the electrodes prepared in Example 5 and Comparative Example 1, where a is the imprinted electrode after elution, b is the non-imprinted electrode after elution, c is the electrode modified with nano-gold copper alloy, d is the imprinted electrode before elution, and e is the non-imprinted electrode before elution.

[0030] Figure 3 Cyclic voltammograms of the electrochemical sensors prepared in Example 5 and Comparative Example 1, where a is the bare acupuncture needle electrode, b is the acupuncture needle electrode modified with nano-gold copper alloy, c is the imprinted electrode before elution, d is the imprinted electrode after elution, e is the non-imprinted electrode before elution, and f is the non-imprinted electrode after elution.

[0031] Figure 4 Differential pulse response curves of the electrochemical sensor prepared in Example 5 in 0.1 mol / L phosphate buffer solution (pH = 7.0) containing different concentrations of chlorpromazine. The chlorpromazine concentrations are 1x10 -6 , 2.5x10 -6 , 5x10 -6 , 1x10 -5 , 2x10 -5 , 4x10 -5 , 6x10 -5 , 8x10 -5 , 1x10 -4 , 2x10 -4 , 4x10 -4 , 6x10 -4 , 8x10 -4 , 1x10 - 3 mol / L.

[0032] Figure 5 SEM images of the Cu / AN electrode obtained by electrodepositing copper nanoparticles on a stainless steel acupuncture needle. The resolution of (a) is 100 nm, and the resolution of (b) is 500 nm.

[0033] Figure 6 SEM images of the Au / Cu / AN electrode obtained by depositing gold nanoparticles on the Cu / AN electrode. The resolution of (a) is 500 nm, and the resolution of (b) is 5 μm. Detailed Description of the Invention

[0034] The following provides a detailed description of the specific embodiments of the present invention. It should be understood that the specific embodiments described herein are only for explaining and illustrating the present invention and are not intended to limit the present invention.

[0035] Example 1: Influence of different molar ratios of template molecule chlorpromazine to monomer 3-aminophenylboronic acid on electrochemical performance

[0036] 1) Pretreatment of acupuncture needles: After polishing the tip of the stainless-steel acupuncture needle with metallographic sandpaper, the polished part was ultrasonically cleaned with ethanol and deionized water for 5 min in sequence, and then dried with nitrogen for standby.

[0037] 2) Modification of nano-copper: The pretreated acupuncture needle electrode was used as the working electrode, the saturated calomel electrode was used as the reference electrode, and the platinum wire electrode was used as the counter electrode. The tip part of the acupuncture needle electrode was immersed in a 5 mM aqueous solution of CuSO4 and deposited by cyclic voltammetry for 5 cycles, with the voltage range of -1.0 V to -0.2 V and the scanning rate of 50 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Cu / ANE, which was dried with nitrogen for standby.

[0038] 3) Modification of nano-gold: The acupuncture needle electrode was immersed in an 8 mM aqueous solution of HAuCl4 and cycled by cyclic voltammetry for 5 cycles, with the voltage range of -1.5 V to 0.5 V and the scanning rate of 25 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Au / Cu / ANE, which was dried with nitrogen for standby.

[0039] 4) Modification of the imprinted polymer film: The acupuncture needle electrode was immersed in a 0.1 mol / L phosphate buffer solution (pH = 7.0) containing 3-aminophenylboronic acid and chlorpromazine with a molar ratio of 1:1, and polymerized by cyclic voltammetry for 20 cycles, with the voltage range of -0.2 V to 1.0 V and the scanning rate of 100 mV / s. Then the electrode was rinsed with deionized water and dried with nitrogen for standby.

[0040] 5) Elution of the template molecule: The prepared electrode was immersed in a solution with a volume ratio of methanol to acetic acid of 9:1 for 10 min to remove the chlorpromazine molecules embedded in the imprinted membrane. Then the electrode was rinsed with deionized water to obtain the imprinted electrode MIP / 3-APBA / Au / Cu / ANE, which was dried with nitrogen for standby.

[0041] The prepared imprinted electrode was immersed in a phosphate buffer solution (pH = 7.0) containing 0.1 mmol / L chlorpromazine, and electrochemical detection was carried out by differential pulse voltammetry. The results are as Figure 1 shown in A. When the molar ratio of 3-aminophenylboronic acid to chlorpromazine is 3:1, the oxidation current value is the largest, indicating that the molar ratio of 3-aminophenylboronic acid to chlorpromazine of 3:1 is the optimal ratio of the monomer to the template molecule in the polymerization solution.

[0042] Example 2: Influence of different pH values of the polymerization solution on electrochemical performance

[0043] 1) Pretreatment of acupuncture needles: After grinding the tip of the stainless-steel acupuncture needle with metallographic sandpaper, the ground part was successively ultrasonically cleaned with ethanol and deionized water for 5 min, and then dried with nitrogen for later use.

[0044] 2) Modification of nano-copper: Using the pretreated acupuncture needle electrode as the working electrode, the saturated calomel electrode as the reference electrode, and the platinum wire electrode as the counter electrode, the tip part of the acupuncture needle electrode was immersed in a 5 mM aqueous CuSO4 solution and deposited by cyclic voltammetry for 5 cycles, with the voltage range of -1.0 V to -0.2 V and the scanning rate of 50 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Cu / ANE, and dried with nitrogen for later use.

[0045] 3) Modification of nano-gold: The acupuncture needle electrode was immersed in an 8 mM aqueous HAuCl4 solution and cycled by cyclic voltammetry for 5 cycles, with the voltage range of -1.5 V to 0.5 V and the scanning rate of 25 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Au / Cu / ANE, and dried with nitrogen for later use.

[0046] 4) Modification of the imprinted polymer film: The acupuncture needle electrode was immersed in a 0.1 mol / L phosphate buffer solution (pH = 5.0 - 9.0) containing 3-aminophenylboronic acid and chlorpromazine in a molar ratio of 3:1, and polymerized by cyclic voltammetry for 20 cycles, with the voltage range of -0.2 V to 1.0 V and the scanning rate of 100 mV / s. Then the electrode was rinsed with deionized water and dried with nitrogen for later use.

[0047] 5) Elution of template molecules: The prepared electrode was immersed in a solution of methanol:acetic acid = 9:1 for 10 min to remove the chlorpromazine molecules embedded in the imprinted membrane. Then the electrode was rinsed with deionized water to obtain the imprinted electrode MIP / 3-APBA / Au / Cu / ANE, and dried with nitrogen for later use.

[0048] The prepared imprinted electrode was immersed in a phosphate buffer solution (pH = 7.0) containing 0.1 mmol / L chlorpromazine, and electrochemical detection was carried out by differential pulse voltammetry. The results are as Figure 1 shown in Figure B. When the pH value of the polymerization solution was 7.0, the oxidation current value was the largest, indicating that pH = 7.0 was the optimal pH value for the polymerization solution of 3-aminophenylboronic acid and chlorpromazine.

[0049] Example 3: Influence of different numbers of electro-polymerization cycles on electrochemical performance during electro-polymerization

[0050] 1) Pretreatment of acupuncture needles: After grinding the tip of the stainless-steel acupuncture needle with metallographic sandpaper, the ground part was successively ultrasonically cleaned with ethanol and deionized water for 5 min, and then dried with nitrogen for later use.

[0051] 2) Modification of nano-copper: The pre-treated acupuncture needle electrode was used as the working electrode, the saturated calomel electrode as the reference electrode, and the platinum wire electrode as the counter electrode. The tip part of the acupuncture needle electrode was immersed in a 5 mM aqueous solution of CuSO4 and deposited for 5 cycles by cyclic voltammetry. The voltage range was -1.0 V to -0.2 V, and the scanning rate was 50 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Cu / ANE, which was dried with nitrogen and reserved for use.

[0052] 3) Modification of nano-gold: The acupuncture needle electrode was immersed in an 8 mM aqueous solution of HAuCl4 and cycled for 5 cycles by cyclic voltammetry. The voltage range was -1.5 V to 0.5 V, and the scanning rate was 25 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Au / Cu / ANE, which was dried with nitrogen and reserved for use.

[0053] 4) Modification of the imprinted polymer membrane: The acupuncture needle electrode was immersed in a 0.1 mol / L phosphate buffer solution (pH = 7.0) containing 3-aminophenylboronic acid and chlorpromazine in a molar ratio of 3:1 and polymerized for 10 - 30 cycles by cyclic voltammetry. The voltage range was -0.2 V to 1.0 V, and the scanning rate was 100 mV / s. Then the electrode was rinsed with deionized water, dried with nitrogen and reserved for use.

[0054] 5) Elution of the template molecule: The prepared electrode was immersed in a solution of methanol:acetic acid = 9:1 for 10 min to remove the chlorpromazine molecules embedded in the imprinted membrane. Then the electrode was rinsed with deionized water to obtain the imprinted electrode MIP / 3-APBA / Au / Cu / ANE, which was dried with nitrogen and reserved for use.

[0055] The prepared imprinted electrode was immersed in a phosphate buffer solution (pH = 7.0) containing 0.1 mmol / L chlorpromazine, and differential pulse voltammetry was used for electrochemical detection. The results are as Figure 1 shown in D. When the number of electropolymerization cycles was 20, the oxidation current value was the largest, indicating that 20 cycles was the optimal number of cycles during electropolymerization.

[0056] Example 4: Influence of different scanning rates on electrochemical performance during electropolymerization

[0057] 1) Pretreatment of the acupuncture needle: After the tip of the stainless steel acupuncture needle was polished with metallographic sandpaper, the polished part was ultrasonically cleaned with ethanol and deionized water for 5 min in sequence, dried with nitrogen and reserved for use.

[0058] 2) Modification of nano - copper: The pretreated acupuncture needle electrode was used as the working electrode, the saturated calomel electrode was used as the reference electrode, and the platinum wire electrode was used as the counter electrode. The tip part of the acupuncture needle electrode was immersed in a 5 mM aqueous solution of CuSO4, and cyclic voltammetry was used to deposit for 5 cycles. The voltage range was - 1.0 V to - 0.2 V, and the scanning rate was 50 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Cu / ANE, and after drying with nitrogen, it was reserved for use.

[0059] 3) Modification of nano - gold: The acupuncture needle electrode was immersed in an 8 mM aqueous solution of HAuCl4, and cyclic voltammetry was used to cycle for 5 cycles. The voltage range was - 1.5 V to 0.5 V, and the scanning rate was 25 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Au / Cu / ANE, and after drying with nitrogen, it was reserved for use.

[0060] 4) Modification of the imprinted polymer film: The acupuncture needle electrode was immersed in a 0.1 mol / L phosphate buffer solution (pH = 7.0) containing 3 - aminophenylboronic acid and chlorpromazine in a molar ratio of 3:1, and cyclic voltammetry was used to polymerize for 20 cycles. The voltage range was - 0.2 V to 1.0 V, and the scanning rate was 25 - 150 mV / s. Then the electrode was rinsed with deionized water, and after drying with nitrogen, it was reserved for use.

[0061] 5) Elution of the template molecule: The prepared electrode was immersed in a solution of methanol: acetic acid = 9:1 for 10 min to remove the chlorpromazine molecules embedded in the imprinted membrane. Then the electrode was rinsed with deionized water to obtain the imprinted electrode MIP / 3 - APBA / Au / Cu / ANE, and after drying with nitrogen, it was reserved for use.

[0062] The prepared imprinted electrode was immersed in a phosphate buffer solution (pH = 7.0) containing 0.1 mmol / L chlorpromazine, and differential pulse voltammetry was used for electrochemical detection. The results are as Figure 1 shown in Figure C. When the electro - polymerization rate was 100 mV / s, the oxidation current value was the largest, indicating that 100 mV / s was the optimal electro - polymerization rate.

[0063] Example 5

[0064] 1) Pretreatment of the acupuncture needle: After the tip of the stainless - steel acupuncture needle was polished with metallographic sandpaper, the polished part was ultrasonically cleaned with ethanol and deionized water for 5 min in sequence, and after drying with nitrogen, it was reserved for use.

[0065] 2) Modification of nano - copper: The pretreated acupuncture needle electrode was used as the working electrode, the saturated calomel electrode was used as the reference electrode, and the platinum wire electrode was used as the counter electrode. The tip part of the acupuncture needle electrode was immersed in a 5 mM aqueous CuSO4 solution and deposited for 5 cycles by cyclic voltammetry. The voltage range was - 1.0 V to - 0.2 V, and the scanning rate was 50 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Cu / ANE, which was dried with nitrogen and reserved for use.

[0066] 3) Modification of nano - gold: The acupuncture needle electrode was immersed in an 8 mM aqueous HAuCl4 solution and cycled for 5 cycles by cyclic voltammetry. The voltage range was - 1.5 V to 0.5 V, and the scanning rate was 25 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Au / Cu / ANE, which was dried with nitrogen and reserved for use.

[0067] 4) Modification of the imprinted polymer membrane: The acupuncture needle electrode was immersed in a 0.1 mol / L phosphate buffer solution (pH = 7.0) containing 3 - aminophenylboronic acid and chlorpromazine in a molar ratio of 3:1 and polymerized for 20 cycles by cyclic voltammetry. The voltage range was - 0.2 V to 1.0 V, and the scanning rate was 100 mV / s. Then the electrode was rinsed with deionized water, dried with nitrogen and reserved for use.

[0068] 5) Elution of the template molecule: The prepared electrode was immersed in a solution of methanol: acetic acid = 9:1 for 10 min to remove the chlorpromazine molecules embedded in the imprinted membrane. Then the electrode was rinsed with deionized water to obtain the imprinted electrode MIP / 3 - APBA / Au / Cu / ANE, which was dried with nitrogen and reserved for use.

[0069] Figure 5 Figure 13 is the SEM image of the Cu / AN electrode obtained by electrodepositing copper nanoparticles on a stainless - steel acupuncture needle. The resolution of (a) is 100 nm, and the resolution of (b) is 500 nm.

[0070] Figure 6 Figure 17 is the SEM image of the Au / Cu / AN electrode obtained by depositing gold nanoparticles on the basis of the Cu / AN electrode. The resolution of (a) is 500 nm, and the resolution of (b) is 5 μm.

[0071] Comparative Example 1

[0072] 1) Pretreatment of the acupuncture needle: After the tip of the stainless - steel acupuncture needle was polished with metallographic sandpaper, the polished part was ultrasonically cleaned with ethanol and deionized water for 5 min in sequence, dried with nitrogen and reserved for use.

[0073] 2) Modification of nano-copper: The pretreated acupuncture needle electrode was used as the working electrode, the saturated calomel electrode was used as the reference electrode, and the platinum wire electrode was used as the counter electrode. The tip part of the acupuncture needle electrode was immersed in a 5 mM aqueous CuSO4 solution and deposited for 5 cycles by cyclic voltammetry. The voltage range was -1.0 V to -0.2 V, and the scanning rate was 50 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Cu / ANE, which was dried with nitrogen and reserved for use.

[0074] 3) Modification of nano-gold: The acupuncture needle electrode was immersed in an 8 mM aqueous HAuCl4 solution and cycled for 5 cycles by cyclic voltammetry. The voltage range was -1.5 V to 0.5 V, and the scanning rate was 25 mV / s. Then the electrode was rinsed with deionized water to obtain the electrode Au / Cu / ANE, which was dried with nitrogen and reserved for use.

[0075] 4) Modification of the polymer film: The acupuncture needle electrode was immersed in a 0.1 mol / L phosphate buffer solution (pH = 7.0) containing 3-aminophenylboronic acid and polymerized for 20 cycles by cyclic voltammetry. The voltage range was -0.2 V to 1.0 V, and the scanning rate was 100 mV / s. Then the electrode was rinsed with deionized water to obtain the non-imprinted electrode, which was dried with nitrogen and reserved for use.

[0076] Test Example 1

[0077] The eluted imprinted electrode (a) (the electrode prepared in Example 5), the eluted non-imprinted electrode (the electrode prepared in Comparative Example 1), the nano-gold copper modified electrode (c) (the electrode prepared in step (3) of Example 5), the imprinted electrode before elution (d) (the electrode prepared in step (4) of Example 5), and the non-imprinted electrode before elution (e) (the electrode prepared in step (4) of Comparative Example 5) were used as the working electrode, the saturated calomel electrode was used as the reference electrode, and the platinum wire electrode was used as the counter electrode. Differential pulse voltammetry was used for detection in a 0.1 mol / L phosphate buffer solution (pH = 7.0) containing 0.1 mmol / L chlorpromazine. The scanning voltage range was 0.2 V to 0.8 V. The results are as follows Figure 2As shown, it can be seen that there are no obvious electrical signals in the visible electrodes before elution (d) and (e). This is because the electrode surface is covered by a polymer film, which hinders the electron transfer between the electrode and chlorpromazine molecules. After elution, the template molecules in the surface-imprinted polymer film of the eluted imprinted electrode (a) are extracted, forming surface-imprinted cavities, which have the properties of adsorbing and fixing chlorpromazine molecules, making it easier for electrons to transfer on the metal surface. A higher current peak is detected in the figure after the imprinted electrode is eluted, indicating that the imprinted electrochemical sensor has been obtained at this time. The non-imprinted electrode (b) does not add the template molecule chlorpromazine when polymerizing 3-aminophenylboric acid, but there will be unpolymerized 3-aminophenylboric acid molecules remaining on the polymer film. When these molecules are eluted, the polymer film becomes porous, which also promotes the electron transfer of chlorpromazine molecules on the internal metal layer, and an electrical signal is also generated during detection. The imprinted electrode (a) provides more imprinting sites than the non-imprinted electrode (b), so its peak current value is higher and the detection performance is better.

[0078] Test Example 2

[0079] The bare acupuncture needle electrode (a), the nano-gold copper modified electrode (b) (the electrode prepared in step (3) of Example 5), the imprinted electrode before elution (c) (the electrode prepared in step (4) of Example 5), the imprinted electrode after elution (d) (the electrode prepared in Example 5), the non-imprinted electrode before elution (e) (the electrode prepared in step (4) of Comparative Example 1), and the non-imprinted electrode after elution (f) (the electrode prepared in Comparative Example 5) were used as working electrodes, the saturated calomel electrode was used as the reference electrode, and the platinum wire electrode was used as the counter electrode. Cyclic voltammetry was used for detection in a 0.1 mol / L phosphate buffer solution (pH = 7.0) containing 0.5 mmol / L chlorpromazine. The scanning voltage range was 0.4 V to 0.9 V, and the scanning voltage rate was 100 mV / s. The results are as Figure 3 shown. The oxidation peak current detected by the imprinted electrode is the largest, indicating that the imprinted electrochemical sensor has been obtained at this time, and the conclusion is consistent with that described in Test Example 1.

[0080] Test Example 3

[0081] Using the saturated calomel electrode as the reference electrode and the platinum wire electrode as the counter electrode, the imprinted electrochemical sensor prepared as described in the steps of Example 5 was used as the working electrode. Electrochemical signals were detected in a 0.1 mol / L phosphate buffer solution (pH = 7.0) containing chlorpromazine with a concentration ranging from 1x10 -3 mol / L to 1x10 -6 mol / L. The results are as Figure 4 shown. As the concentration of chlorpromazine in the solution increases, its peak current value also increases.

[0082] The above embodiments are not limitations on the present invention. The present invention is not limited to the above embodiments. As long as it meets the requirements of the present invention, it falls within the protection scope of the present invention.

Claims

1. A preparation method of an imprinted electrochemical sensor for detecting chlorpromazine, wherein the imprinted electrochemical sensor uses a saturated calomel electrode as a reference electrode, a platinum wire electrode as a counter electrode, and an imprinted working electrode as a working electrode; characterized in that The imprinted working electrode is prepared by the following steps: Step (1), pretreatment of the stainless-steel acupuncture needle; After the tip of the stainless-steel acupuncture needle is polished with metallographic sandpaper, the polished part is ultrasonically cleaned with ethanol and deionized water in sequence, and then dried with nitrogen for standby; Step (2), modification of nano-copper; The tip part of the acupuncture needle electrode is immersed in an aqueous CuSO4 solution, and metal Cu is deposited by cyclic voltammetry to obtain the electrode Cu / ANE; wherein the voltage range of cyclic voltammetry is -1.0V to -0.2V; The number of deposition cycles is 5, and the deposition rate is 50mV / s; Step (3), modification of nano-gold; The acupuncture needle electrode is immersed in an aqueous HAuCl4 solution, and metal Au is deposited by cyclic voltammetry to obtain the electrode Au / Cu / ANE; wherein the voltage range of cyclic voltammetry is -1.5V to 0.5V; the number of deposition cycles is 5, and the deposition rate is 25mV / s; Step (4), modification of the imprinted polymer film; The acupuncture needle electrode is immersed in a phosphate buffer solution containing the monomer 3-aminophenylboronic acid and the template molecule chlorpromazine, and a molecularly imprinted polymer film is electro-polymerized on the surface of the acupuncture needle by cyclic voltammetry; wherein the molar ratio of 3-aminophenylboronic acid to chlorpromazine is 1:1 to 1:5, and the voltage range of cyclic voltammetry is -0.2V to 1.0V; the number of deposition cycles is 20, and the deposition rate is 100mV / s; Step (5), elution of the template molecule The prepared electrode is immersed in an eluent to remove the chlorpromazine molecules embedded in the imprinted membrane, so that an imprinted cavity capable of specifically recognizing chlorpromazine molecules is formed on the polymer film, and the final imprinted working electrode is obtained.

2. The method according to claim 1, wherein The concentration of the CuSO4 aqueous solution in step (2) is 5mmol / L.

3. The method according to claim 1, characterized in that The concentration of the HAuCl4 aqueous solution in step (3) is 8mmol / L.

4. The method according to claim 1, wherein The pH value of the buffer solution in step (4) is 5.0 to 9.

0.

5. The method according to claim 1, wherein In step (5), the eluent uses a solution with a volume ratio of methanol: acetic acid of 9:

1.

6. An imprinted electrochemical sensor for detecting chlorpromazine, using a saturated calomel electrode as the reference electrode, a platinum wire electrode as the counter electrode, and the imprinted working electrode prepared by any one of the methods of claims 1-5 as the working electrode.

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