An electrochemical method for the detection of 3-amino-2-oxazolidinone
By preparing conjugated microporous polymer and gold nanoparticle-modified electrodes on screen-printed carbon electrodes, and combining them with differential pulse voltammetry, the problems of high cost or high false positive rate of existing detection methods are solved, realizing low-cost, rapid and sensitive detection of 3-amino-2-oxazolidinone, which is suitable for monitoring furazolidone metabolites in food.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHONGKAI UNIV OF AGRI & ENG
- Filing Date
- 2023-10-16
- Publication Date
- 2026-06-26
AI Technical Summary
Existing methods for detecting 3-amino-2-oxazolidinone suffer from problems such as expensive instruments, high levels of expertise required, or high false positive rates, making it difficult to achieve rapid, sensitive, and low-cost on-site analysis.
An electrochemical detection method was established by using a screen-printed carbon electrode modified with conjugated microporous polymers and gold nanoparticles, combined with differential pulse voltammetry. The method involves preparing CMP/AuNPs/SPCE on the electrode surface for the detection of 3-amino-2-oxazolidinone.
A lightweight, portable, low-cost, and simple detection method is provided, which can rapidly and sensitively detect 3-amino-2-oxazolidinone in animal-derived foods, significantly improving charge transfer rate and response current, and is suitable for monitoring furazolidone metabolites.
Abstract
Description
Technical Field
[0001] This invention relates to the field of electrochemical detection technology, specifically to an electrochemical detection method for 3-amino-2-oxazolidinone. Background Technology
[0002] 3-Amino-2-oxazolidinone (AOZ) is a metabolite of furazolidone. Because furazolidone is metabolized rapidly in vivo, and its metabolite 3-amino-2-oxazolidinone remains stable after binding to proteins, it exhibits significant toxic side effects. Therefore, establishing a rapid detection method for 3-amino-2-oxazolidinone is of great importance for comprehensively monitoring furazolidone residues and promoting food quality and safety.
[0003] Currently, the main methods for detecting 3-amino-2-oxazolidinone (AOZ) include high-performance liquid chromatography (HPLC) and immunochromatography. HPLC is accurate and sensitive, but the instruments are expensive and highly specialized, making it difficult to perform on-site analysis. Immunochromatography is simple, sensitive, and specific, but has a high false positive rate. Electrochemical methods offer advantages such as ease of operation, speed, sensitivity, and low cost; however, there are few reports on the electrochemical analysis of AOZ. Therefore, we propose an electrochemical detection method for 3-amino-2-oxazolidinone. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides an electrochemical detection method for 3-amino-2-oxazolidinone, which solves the problems mentioned in the background section.
[0005] To achieve the above objectives, the present invention provides an electrochemical detection method for 3-amino-2-oxazolidinone, comprising the following specific steps:
[0006] (1) Preparation of conjugated microporous polymers
[0007] Place triaminoguanidine hydrochloride in a 250mL three-necked flask, add 60mL of water, heat to 80℃, and then slowly add 80mL of tris(4-formylphenyl)amine tetrahydrofuran solution under electromagnetic stirring.
[0008] After reacting for 12 hours, the sample was washed and filtered with water-tetrahydrofuran solution. Finally, the sample was dried in a vacuum oven at 80°C to obtain a reddish-brown solid powder, which is the CMP product. The product was then stored in a dehumidifying cabinet for later use.
[0009] (2) Preparation of gold nanoparticles
[0010] Take 1 mL of chloroauric acid solution in a beaker, add 99 mL of water, heat to boiling with a constant temperature magnetic stirrer, and then add 6 mL of 1% sodium citrate dropwise.
[0011] Then heat until the reaction solution turns wine red, stop heating, continue stirring for 15 minutes, and then cool naturally to room temperature. Make up to 100 mL with pure water to obtain the AuNPs product, and store it in a refrigerator at 4°C for later use.
[0012] (3) Preparation of CMP / AuNPs / SPCE
[0013] 5 μL of AuNPs was dropped onto the surface of SPCE and air-dried at room temperature to obtain AuNPs / SPCE;
[0014] Then, 2 mg of CMP was ultrasonically dispersed in 2 mL of ultrapure water. After uniform dispersion, 5 μL of CMP dispersion was drop-coated onto the surface of AuNPs / SPCE. After drying at room temperature, CMP / AuNPs / SPCE was obtained, which is the modified electrode for measuring AOZ.
[0015] Furthermore, the electrochemical detection method for 3-amino-2-oxazolidinone also includes the following specific steps:
[0016] (4) Electrochemical detection of AOZ
[0017] 30 μL of 0.1 mol / L PBS solution containing AOZ was dropped onto the surface of CMP / AuNPs / SPCE. After standing for 30 s, differential pulse voltammetry was performed at -0.6 to 0.6 V, with a potential increment of 6 mV and a potential amplitude of 50 mV to obtain the relationship curve between different response current values (I) and potential (E).
[0018] Furthermore, the electrochemical detection method for 3-amino-2-oxazolidinone also includes the following specific steps:
[0019] (5) Characterization of CMP / AuNPs / SPCE
[0020] A. Cyclic voltammetry (CV): 30 μL of 5 mmol / L K3Fe(CN)6 solution is dropped onto the surface of SPCE or modified electrode. Cyclic voltammetry is used to scan one cycle at a potential of -0.5 to 0.8 V and a scan rate of 50 mV / s to obtain the electrochemical response of K3Fe(CN)6 on the electrode.
[0021] B. Electrochemical impedance spectroscopy (EIS): 30 μL of 5 mmol / L K3Fe(CN)6 solution is dropped onto the surface of SPCE or modified electrode. The electrode is characterized by AC impedance spectroscopy at an amplitude of 5 mV and a frequency range of 0.1–100,000 Hz to obtain the AC impedance spectrum.
[0022] Furthermore, in the preparation of the conjugated microporous polymer in step (1), the triaminoguanidine hydrochloride is specifically 0.281 g and 2 mmol.
[0023] Furthermore, in the preparation process of the conjugated microporous polymer in step (1), the electromagnetic stirring rate is 240 r / min.
[0024] Furthermore, in the preparation of the conjugated microporous polymer in step (1), the tri(4-formylphenyl)amine in the tetrahydrofuran solution is specifically 0.658 g and 2 mmol.
[0025] Furthermore, in the preparation of the conjugated microporous polymer in step (1), the volume ratio of water to tetrahydrofuran in the water-tetrahydrofuran solution is 1:4.
[0026] Furthermore, in the preparation process of gold nanoparticles in step (2), the glassware to be used in the experiment must first be cleaned with nitric acid-hydrochloric acid solution before preparation, wherein the volume ratio of nitric acid to hydrochloric acid is 1:3.
[0027] Furthermore, in step (2) of the preparation of gold nanoparticles, the concentration of the chloroauric acid solution is 0.01%.
[0028] Furthermore, in step (4) of the electrochemical detection of AOZ, the pH of the PBS solution is 7.0.
[0029] This invention provides an electrochemical detection method for 3-amino-2-oxazolidinone, which has the following advantages: This method involves drop-coating gold nanoparticles (AuNPs) with large specific surface area and excellent conductivity, along with a conjugated microporous polymer (CMP), onto the surface of a screen-printed carbon electrode (SPCE) to prepare an electrochemically modified electrode for AOZ determination: CMP / AuNPs / SPCE. An electrochemical detection method for AOZ determination based on this modified electrode is established using differential pulse voltammetry. This modified electrode is lightweight and portable, and its preparation method is simple and easy to implement, facilitating batch production. It is readily available and cost-effective, requiring only 30 μL of sample, and can be used for rapid on-site detection of furazolidone metabolite AOZ in animal-derived foods, providing a new technical means for monitoring furazolidone metabolite AOZ in food. Furthermore, the large specific surface area and active groups on the surface of AuNPs and CMPs provide more interaction sites, which is conducive to AOZ reaching the electrode surface and undergoing oxidation. In addition, AuNPs and CMPs have a good synergistic effect, which has a good electrocatalytic effect on the oxidation of AOZ, significantly improving the charge transfer rate and significantly enhancing the response current of AOZ on CMP / AuNPs / SPCE. Detailed Implementation
[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to specific embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0031] An electrochemical detection method for 3-amino-2-oxazolidinone, comprising the following specific steps:
[0032] (1) Preparation of conjugated microporous polymers
[0033] Place triaminoguanidine hydrochloride in a 250mL three-necked flask, add 60mL of water, heat to 80℃, and then slowly add 80mL of tris(4-formylphenyl)amine tetrahydrofuran solution under electromagnetic stirring.
[0034] After reacting for 12 hours, the sample was washed and filtered with water and tetrahydrofuran. Finally, the sample was dried in a vacuum oven at 80°C to obtain a reddish-brown solid powder, which is the CMP product. The product was then stored in a dehumidifying cabinet for later use.
[0035] (2) Preparation of gold nanoparticles
[0036] Take 1 mL of chloroauric acid solution in a beaker, add 99 mL of water, heat to boiling with a constant temperature magnetic stirrer, and then add 6 mL of 1% sodium citrate dropwise.
[0037] Then heat until the reaction solution turns wine red, stop heating, continue stirring for 15 minutes, and then cool naturally to room temperature. Make up to 100 mL with pure water to obtain the AuNPs product, and store it in a refrigerator at 4°C for later use.
[0038] (3) Preparation of CMP / AuNPs / SPCE
[0039] 5 μL of AuNPs was dropped onto the surface of SPCE and air-dried at room temperature to obtain AuNPs / SPCE;
[0040] Then, 2 mg of CMP was ultrasonically dispersed in 2 mL of ultrapure water. After uniform dispersion, 5 μL of CMP dispersion was drop-coated onto the surface of AuNPs / SPCE. After drying at room temperature, CMP / AuNPs / SPCE was obtained, which is the modified electrode for measuring AOZ.
[0041] The electrochemical detection method for 3-amino-2-oxazolidinone also includes the following specific steps:
[0042] (4) Electrochemical detection of AOZ
[0043] 30 μL of 0.1 mol / L PBS solution containing AOZ was dropped onto the surface of CMP / AuNPs / SPCE. After standing for 30 s, differential pulse voltammetry was performed at -0.6 to 0.6 V, with a potential increment of 6 mV and a potential amplitude of 50 mV to obtain the relationship curve between different response current values (I) and potential (E).
[0044] The electrochemical detection method for 3-amino-2-oxazolidinone also includes the following specific steps:
[0045] (5) Characterization of CMP / AuNPs / SPCE
[0046] A. Cyclic voltammetry (CV): 30 μL of 5 mmol / L K3Fe(CN)6 solution is dropped onto the surface of SPCE or modified electrode. Cyclic voltammetry is used to scan one cycle at a potential of -0.5 to 0.8 V and a scan rate of 50 mV / s to obtain the electrochemical response of K3Fe(CN)6 on the electrode.
[0047] B. Electrochemical impedance spectroscopy (EIS): 30 μL of 5 mmol / L K3Fe(CN)6 solution is dropped onto the surface of SPCE or modified electrode. The electrode is characterized by AC impedance spectroscopy at an amplitude of 5 mV and a frequency range of 0.1–100,000 Hz to obtain the AC impedance spectrum.
[0048] In step (1) the preparation of the conjugated microporous polymer, the amount of triaminoguanidine hydrochloride is 0.281 g and 2 mmol. In step (1) the preparation of the conjugated microporous polymer, the electromagnetic stirring speed is 240 r / min. In step (1) the preparation of the conjugated microporous polymer, the amount of tri(4-formylphenyl)amine in the tetrahydrofuran solution is 0.658 g and 2 mmol. In step (1) the preparation of the conjugated microporous polymer, the volume ratio of water to tetrahydrofuran in the water-tetrahydrofuran solution is 1:4. In step (2) the preparation of gold nanoparticles, the glassware to be used in the experiment must first be cleaned with nitric acid-hydrochloric acid solution before preparation, wherein the volume ratio of nitric acid to hydrochloric acid is 1:3. In step (2) the preparation of gold nanoparticles, the concentration of chloroauric acid solution is 0.01%. In step (4) the electrochemical detection of AOZ, the pH of the PBS solution is 7.0.
[0049] Example 1
[0050] Chicken samples were cut into small pieces and pulverized evenly. 2.0 g (±0.01 g) of the chicken sample was then weighed into a 50 mL centrifuge tube, 10 mL of ethyl acetate was added, and the mixture was ultrasonically extracted for 10 min. After centrifugation at 10000 r / min for 10 min, the supernatant was collected. This process was repeated once, and the supernatants were combined. 10 mL of n-hexane was added to remove fat. After centrifugation, the lower layer was collected and rotary evaporated at 30℃ until the ethyl acetate was completely removed. 5 mL of pH 7.0 PBS was added to dissolve the effluent before testing. For detection, 30 μL of the chicken sample solution was dropped onto a CMP / AuNPs / SPCE surface. After standing for 30 s, differential pulse voltammetry was performed at -0.6 to 0.6 V, with a potential increment of 6 mV and a potential amplitude of 50 mV. The relationship curve between different response current values (I) and potential (E) was obtained, allowing the detection of AOZ in the chicken sample.
[0051] Example 2
[0052] Cut the beef sample into small pieces and grind it evenly. Then weigh 2.0 g (±0.01 g) of the beef sample into a 50 mL centrifuge tube, add 10 mL of ethyl acetate, and extract by sonication for 10 min. Centrifuge at 10000 r / min for 10 min and take out the supernatant. Repeat the operation once and combine the supernatants. Evaporate at 30℃ until the ethyl acetate is completely removed. Add 5 mL of pH 7.0 PBS to dissolve and then test. For detection, drop 30 μL of the beef sample solution to be tested onto a CMP / AuNPs / SPCE surface. After standing for 30 s, perform differential pulse voltammetry scanning under the conditions of -0.6 to 0.6 V, potential increment of 6 mV, and potential amplitude of 50 mV. Obtain the relationship curve between different response current values (I) and potential (E), and the AOZ contained in the beef sample can be detected.
[0053] Example 3
[0054] Weigh 3.0 g (±0.01 g) of milk sample into a 50 mL centrifuge tube, add 30 mL of pH 7.0 PBS, sonicate for 10 min, centrifuge at 10000 r / min for 10 min, take out the supernatant, repeat the centrifugation once for the remaining liquid, and combine the supernatants for testing; for detection, drop 30 μL of the milk sample solution to be tested onto the CMP / AuNPs / SPCE surface, let stand for 30 s, and then perform differential pulse voltammetry scanning under the conditions of -0.6 to 0.6 V, potential increment of 6 mV, and potential amplitude of 50 mV to obtain the relationship curve between different response current values (I) and potential (E), and the AOZ contained in the milk sample can be detected.
[0055] Example 4
[0056] Weigh 3.0 g (±0.01 g) of honey sample into a 50 mL centrifuge tube, add 30 mL of pH 7.0 PBS to dissolve, centrifuge at 10000 r / min for 10 min, and take the supernatant for testing; during detection, drop 30 μL of the honey sample solution to be tested onto the CMP / AuNPs / SPCE surface, let stand for 30 s, and then perform differential pulse voltammetry scanning under the conditions of -0.6 to 0.6 V, potential increment of 6 mV, and potential amplitude of 50 mV to obtain the relationship curve between different response current values (I) and potential (E), which can detect the AOZ contained in the honey sample.
[0057] In summary, the electrochemical detection method for this 3-amino-2-oxazolidinone includes the following specific steps:
[0058] (1) Preparation of conjugated microporous polymer: Triaminoguanidine hydrochloride (0.281 g, 2 mmol) was placed in a 250 mL three-necked flask, 60 mL of water was added, and the mixture was heated to 80 °C. Then, 80 mL of tris(4-formylphenyl)amine (0.658 g, 2 mmol) tetrahydrofuran solution was slowly added under electromagnetic stirring at a rate of 240 r / min. After reacting for 12 h, the mixture was washed and filtered with water-tetrahydrofuran solution, where the volume ratio of water to tetrahydrofuran was 1:4. Finally, the obtained sample was dried in a vacuum oven at 80 °C to obtain a reddish-brown solid powder, i.e., the CMP product, which was then stored in a dehumidifying cabinet for later use.
[0059] (2) Preparation of gold nanoparticles: Before preparation, the glassware to be used in the experiment should be cleaned with nitric acid-hydrochloric acid solution, in which the volume ratio of nitric acid to hydrochloric acid is 1:3. Take 1 mL of chloroauric acid solution (0.01%) in a beaker and add 99 mL of water. Heat to boiling with a constant temperature magnetic stirrer, and then add 6 mL of 1% sodium citrate dropwise. Then heat until the reaction solution turns wine red, stop heating, continue stirring for 15 min and cool naturally to room temperature. Make up to 100 mL with pure water to obtain AuNPs product, and store it in a refrigerator at 4℃ for later use.
[0060] (3) Preparation of CMP / AuNPs / SPCE: 5 μL of AuNPs was dropped onto the surface of SPCE and dried at room temperature to obtain AuNPs / SPCE; then 2 mg of CMP was ultrasonically dispersed in 2 mL of ultrapure water. After uniform dispersion, 5 μL of CMP dispersion was dropped onto the surface of AuNPs / SPCE and dried at room temperature to obtain CMP / AuNPs / SPCE, which is the modified electrode for measuring AOZ.
[0061] (4) Electrochemical detection of AOZ: 30 μL of 0.1 mol / L PBS solution containing AOZ was dropped onto the CMP / AuNPs / SPCE surface, where the pH of the PBS solution was 7.0. After standing for 30 s, differential pulse voltammetry was performed at -0.6 to 0.6 V, with a potential increment of 6 mV and a potential amplitude of 50 mV to obtain the relationship curve between different response current values (I) and potential (E).
[0062] (5) Characterization of CMP / AuNPs / SPCE
[0063] A. Cyclic voltammetry (CV): 30 μL of 5 mmol / L K3Fe(CN)6 solution is dropped onto the surface of SPCE or modified electrode. Cyclic voltammetry is used to scan one cycle at a potential of -0.5 to 0.8 V and a scan rate of 50 mV / s to obtain the electrochemical response of K3Fe(CN)6 on the electrode.
[0064] B. Electrochemical impedance spectroscopy (EIS): 30 μL of 5 mmol / L K3Fe(CN)6 solution is dropped onto the surface of SPCE or modified electrode. The electrode is characterized by AC impedance spectroscopy at an amplitude of 5 mV and a frequency range of 0.1–100,000 Hz to obtain the AC impedance spectrum.
[0065] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. An electrochemical detection method for 3-amino-2-oxazolidinone, characterized in that, The electrochemical detection method for 3-amino-2-oxazolidinone includes the following specific steps: (1) Preparation of conjugated microporous polymer (CMP) Place triaminoguanidine hydrochloride in a 250 mL three-necked flask, add 60 mL of water, heat to 80 °C, and then slowly add 80 mL of tris(4-formylphenyl)amine tetrahydrofuran solution under electromagnetic stirring; After reacting for 12 h, the sample was washed and filtered with water-tetrahydrofuran solution. Finally, the sample was dried in a vacuum oven at 80 °C to obtain a reddish-brown solid powder, which is the CMP product. The product was then stored in a dehumidifying cabinet for later use. (2) Preparation of gold nanoparticles Take 1 mL of chloroauric acid solution in a beaker, add 99 mL of water, heat to boiling with a constant temperature magnetic stirrer, and then add 6 mL of 1% sodium citrate dropwise. Then heat until the reaction solution turns wine red, stop heating, continue stirring for 15 min, and then cool naturally to room temperature. Make up to 100 mL with pure water to obtain the AuNPs product, and store it in a refrigerator at 4 ℃ for later use. (3) Preparation of CMP / AuNPs / SPCE 5 µL of AuNPs was dropped onto the SPCE surface and air-dried at room temperature to obtain AuNPs / SPCE; Then, 2 mg of CMP was ultrasonically dispersed in 2 mL of ultrapure water. After uniform dispersion, 5 µL of CMP dispersion was drop-coated onto the surface of AuNPs / SPCE. After drying at room temperature, CMP / AuNPs / SPCE was obtained, which is the modified electrode for measuring AOZ. (4) Electrochemical detection of AOZ 30 µL of 0.1 mol / L PBS solution containing AOZ was dropped onto the surface of CMP / AuNPs / SPCE. After standing for 30 s, differential pulse voltammetry was performed at -0.6 to 0.6 V, with a potential increment of 6 mV and a potential amplitude of 50 mV to obtain the relationship curve between different response current values (I) and potential (E).
2. The electrochemical detection method for 3-amino-2-oxazolidinone according to claim 1, characterized in that: In the preparation of the conjugated microporous polymer in step (1), the triaminoguanidine hydrochloride is specifically 0.281 g and 2 mmol.
3. The electrochemical detection method for 3-amino-2-oxazolidinone according to claim 1, characterized in that: In step (1), during the preparation of the conjugated microporous polymer, the electromagnetic stirring rate is 240 r / min.
4. The electrochemical detection method for 3-amino-2-oxazolidinone according to claim 1, characterized in that: In the preparation of the conjugated microporous polymer in step (1), the tri(4-formylphenyl)amine in the tetrahydrofuran solution is specifically 0.658 g and 2 mmol.
5. The electrochemical detection method for 3-amino-2-oxazolidinone according to claim 1, characterized in that: In the preparation of the conjugated microporous polymer in step (1), the volume ratio of water to tetrahydrofuran in the water-tetrahydrofuran solution is 1:
4.
6. The electrochemical detection method for 3-amino-2-oxazolidinone according to claim 1, characterized in that: In the preparation of gold nanoparticles in step (2), the glassware to be used in the experiment must be cleaned with nitric acid-hydrochloric acid solution before preparation, wherein the volume ratio of nitric acid to hydrochloric acid is 1:
3.
7. The electrochemical detection method for 3-amino-2-oxazolidinone according to claim 1, characterized in that: In step (2), during the preparation of gold nanoparticles, the concentration of the chloroauric acid solution is 0.01%.
8. The electrochemical detection method for 3-amino-2-oxazolidinone according to claim 1, characterized in that: In step (4) of the electrochemical detection of AOZ, the pH of the PBS solution is 7.0.