Functionalized integrated carbon compound-based niclosamide electrochemical sensor and preparation method thereof

Abstract

The invention belongs to the field of electrochemical sensors, and relates to a functionalized integrated carbon compound-based niclosamide electrochemical sensor and a preparation method thereof. A Zn-MOF (at) CNF (at) GCNT nano composite material prepared from a zinc-based metal organic framework material (Zn-MOF), carbon nanoflowers (CNF) and graphitized carbon nanotubes (GCNT) is modified on the surface of a glassy carbon electrode (GCE) to form a Zn-MOF (at) CNF (at) GCNT / GCE working electrode. The preparation method comprises the following steps: firstly, uniformly dispersing CNF and GCNT which are equal in mass in a N, N-dimethylformamide (DMF) solution through magnetic stirring in an ultrasonic environment; then, adding Zn-MOF into the solution, and carrying out ultrasonic dispersion to obtain a uniformly mixed black Zn-MOF (at) CNF (at) GCNT suspension; and finally, dispensing the Zn-MOF (at) CNF (at) GCNT mixture uniform suspension onto the surface of the GCE, and drying under an infrared lamp to prepare the working electrode Zn-MOF (at) CNF (at) GCNT / GCE modified by the Zn-MOF (at) CNF (at) GCNT nano composite material. Based on the synergistic interaction effect generated by the Zn-MOF, the GCNT and the CNF, the Zn-MOF (at) CNF (at) GCNT / GCE sensor is high in sensitivity, the detection limit can reach 7.68 nM, and the niclosamide sensing detection performance is excellent.

Description

Technical Field

[0001] The invention belongs to the field of electrochemical sensors and relates to a functionalized integrated carbon composite-based niclosamide electrochemical sensor and a preparation method thereof. Background Art

[0002] Niclosamide is a salicylamide derivative, a yellow-white crystalline powder, odorless and tasteless. It is insoluble in water, but soluble in hot ethanol, chloroform and other organic solvents. This substance can be used as an effective antiparasitic drug, mainly for the treatment of tapeworm infections, including beef tapeworm (Taenia saginata), pork tapeworm (Taenia solium) and short tapeworm. Its mechanism of action is to inhibit the oxidative phosphorylation process of mitochondria in the worm cells, reduce the generation of energy substance ATP, cause the head segment and adjacent segments of the tapeworm to deteriorate, and the worm body falls off the intestinal wall and is excreted from the body with feces. In addition, niclosamide can also be used as a molluscicide, which can effectively kill Oncomelania snails and Schistosoma japonicum cercariae, and is effective against Oncomelania snails and snail eggs. This substance can rapidly produce metabolic changes in water and has a short action time, which makes it useful in killing unwanted fish in commercial fish ponds. Because of its short half-life in water, it only takes a few days after use before new fish can be put in. If used improperly, it may cause some adverse reactions, including dizziness, chest tightness, chest pain, fatigue, gastrointestinal discomfort, fever, itching, etc.

[0003] In recent years, electrochemical sensor detection methods have attracted more and more attention due to their advantages such as high efficiency, sensitivity, low cost and easy miniaturization. Compared with traditional detection and analysis technologies, electrochemical sensors can effectively overcome the problems of expensive traditional detection and analysis hardware equipment, large equipment space, complex specialized operations, long detection and analysis cycles, and difficulty in realizing portable on-site detection of niclosamide outdoors. However, the electrochemical sensing detection technology for niclosamide is still immature and needs further improvement. Therefore, it is particularly urgent to develop a low-cost, fast, and highly sensitive electrochemical sensing detection technology for niclosamide.

[0004] The Chinese invention patent (publication number: CN115728365A) provides an electrochemical sensor for highly sensitive detection of niclosamide and a detection method thereof, wherein the electrochemical sensor is composed of a GCE glassy carbon electrode surface modified with an ECP-600JD / ZIF-67 nanocomposite prepared from Ketjen black carbon black nanoparticles ECP-600J and metal organic framework material ZIF-67. ECP-600JD is uniformly dispersed in a DMF solution, and then an equal amount of ZIF-67 is added to the above solution, and a uniform mixed suspension is obtained by ultrasonic dispersion. Finally, 5 μL of the above uniform suspension is drop-coated on the surface of the glassy carbon electrode and dried under an infrared lamp to obtain a working electrode modified with an ECP-600JD / ZIF-67 nanocomposite. The disadvantage of this method is that the ECP-600JD Ketjen black carbon black nanoparticles used. A conductive network with a branched morphology is formed by "point-to-point" contact, and there are still certain deficiencies in enhancing the charge transfer efficiency.

[0005] The information disclosed in this background section is only intended to enhance understanding of the overall background of the invention and should not be taken as an acknowledgement or any form of suggestion that the information constitutes the prior art known to a person skilled in the art. Summary of the invention

[0006] The object of the present invention is to provide a functional integrated carbon composite-based niclosamide electrochemical sensor and a preparation method thereof. The electrochemical sensor prepared by the method can effectively overcome the shortcomings of traditional detection methods, such as expensive detection and analysis hardware equipment, large equipment space volume, complex specialized operations, long detection and analysis cycle, and difficulty in realizing portable on-site detection of niclosamide outdoors. The electrochemical sensor has low cost, high speed, high sensitivity, small space volume, easy to carry, and easy to realize portable on-site detection of niclosamide outdoors.

[0007] In order to achieve the above object, the technical solution of the present invention is:

[0008] A functionalized integrated carbon composite-based niclosamide electrochemical sensor is disclosed. The Zn-MOF@CNF@GCNT nanocomposite material prepared from zinc-based metal organic framework material (Zn-MOF), carbon nanoflowers (CNF) and graphitized carbon nanotubes (GCNT) is modified on the surface of a glassy carbon electrode (GCE) to form a Zn-MOF@CNF@GCNT / GCE working electrode. The Zn-MOF@CNF@GCNT / GCE working electrode, auxiliary electrode and reference electrode are placed in an electrolytic cell to form a functionalized integrated carbon composite-based niclosamide electrochemical sensor.

[0009] In the functionalized integrated carbon composite-based niclosamide electrochemical sensor, the content range of each component in the Zn-MOF@CNF@GCNT nanocomposite material is as follows: the mass proportion of Zn-MOF is 30-50%, the mass proportion of CNF is 25-35%, and the mass proportion of GCNT is 25-35%.

[0010] In the functionalized integrated carbon composite-based niclosamide electrochemical sensor, the thickness of the Zn-MOF@CNF@GCNT nanocomposite material on the GCE surface is 80 to 200 μm.

[0011] The method for preparing the functionalized integrated carbon composite-based niclosamide electrochemical sensor comprises the following steps:

[0012] (1) Preparation of a uniform Zn-MOF@CNF@GCNT suspension: First, equal amounts of CNF and GCNT were added to a N,N-dimethylformamide (DMF) solution and continuously magnetically stirred under an ultrasonic environment to obtain a uniformly dispersed black CNF@GCNT suspension. Subsequently, a certain amount of Zn-MOF was added to the suspension, with the Zn-MOF addition ratio being 30-50% of the total mass of Zn-MOF, CNF and GCNT, and the mixture was dispersed and mixed uniformly under ultrasonic conditions again to obtain a uniformly mixed Zn-MOF@CNF@GCNT suspension.

[0013] (2) Preparation of Zn-MOF@CNF@GCNT / GCE working electrode: The above-mentioned Zn-MOF@CNF@GCNT uniform suspension was drop-coated on the pre-polished GCE surface and dried under an infrared lamp to obtain a Zn-MOF@CNF@GCNT / GCE working electrode;

[0014] (3) Preparation of an electrochemical sensor for highly sensitive detection of niclosamide: Using a platinum wire electrode as an auxiliary electrode and a saturated calomel electrode as a reference electrode, the above-mentioned Zn-MOF@CNF@GCNT / GCE working electrode, auxiliary electrode and reference electrode were placed in a three-electrode glass electrolytic cell to form a functionalized integrated carbon composite-based niclosamide electrochemical sensor.

[0015] Furthermore, in the step (1), the ultrasonic dispersion time is 60 to 180 minutes, and the ultrasonic power is 180W.

[0016] Furthermore, in step (2), the infrared lamp drying time is 5 to 15 minutes.

[0017] Furthermore, in step (2), in order to construct the target working electrode, the surface of the glassy carbon electrode is pretreated by wet sand grinding, and the surface of the glassy carbon electrode is polished by ultrasonic cleaning to obtain a glassy carbon electrode with a clean surface and free of impurities.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] (1) The Zn-MOF@CNF@GCNT nanocomposite material used in the present invention as a sensitizer for the sensor working electrode can overcome the shortcomings of the conventional working electrode, such as weak adsorption capacity of the electrolyte, low charge transport efficiency, and weak enrichment capacity of chloramphenicol molecules on the working electrode surface.

[0020] (2) The Zn-MOF used in the present invention is a zinc-based metal organic framework material, which has high thermal and chemical stability, high catalytic activity, large specific surface area and unique morphology and structure, which can provide a large number of adsorption, reaction and active sites.

[0021] (3) The CNF used in the present invention is a carbon nanoflower, which is a new type of carbon-based material that looks like a flower and has a unique petal-like structure. This material is usually composed of carbon nanotubes, graphene or other carbon nanostructures, showing a unique petal-like or similar structure. It has the following advantages: (i) High specific surface area: Carbon nanoflowers have a very high specific surface area due to their porous three-dimensional structure; (ii) Excellent electrical conductivity: Carbon nanoflowers have good electrical conductivity, which helps to enhance the charge transport capacity of nanocomposites; (iii) Chemical stability: Carbon nanoflowers have extremely high chemical stability and can maintain their performance under various environments; (iv) Unique morphology: The petal-like structure of carbon nanoflowers provides more active sites, which helps to promote electrochemical reactions. In addition, graphitized carbon nanotubes have excellent electrical conductivity. Graphitization treatment can transform crystalline carbon into crystalline carbon, increase the proportion of sp2 hybridization between carbon atoms, and improve the mobility of electrons, thereby improving the electrical conductivity of carbon nanotubes. Because the arrangement of carbon atoms in the graphitization process is more orderly, the structural integrity of the tube wall is enhanced, and graphitized carbon nanotubes have higher mechanical strength and toughness, as well as stronger chemical stability. In addition, graphitized carbon nanotubes have better adsorption properties due to their increased specific surface area and improved pore structure.

[0022] (5) The Zn-MOF@CNF@GCNT nanocomposite material used in the present invention can fully utilize the advantages of the above nanocomposite materials, exhibit a synergistic effect, and significantly improve the conductivity of the working electrode modified coating and the adsorption and enrichment capacity of chloranilamide.

[0023] (5) The sensor prepared based on the Zn-MOF@CNF@GCNT nanocomposite material of the present invention has the advantages of being simple, efficient, low cost, highly sensitive, and easy to carry in detecting niclosamide, and can easily realize portable on-site detection of niclosamide outdoors. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 CV curves of the Zn-MOF@CNF@GCNT / GCE sensor and the unmodified sensor for detecting niclosamide prepared in Example 1 of the present invention. In the figure, the abscissa E represents the potential (V vs SCE), and the ordinate I represents the current (μA).

[0025] Figure 2 This is the DPV curve of niclosamide detected by the Zn-MOF@CNF@GCNT / GCE sensor prepared in Example 1 of the present invention. In the figure, the abscissa E represents the potential (V vs SCE), and the ordinate I represents the current (μA). DETAILED DESCRIPTION

[0026] In the specific implementation process, the present invention proposes a functional integrated carbon composite-based niclosamide electrochemical sensor and a preparation method thereof, wherein a Zn-MOF@CNF@GCNT nanocomposite material prepared from a zinc-based metal organic framework material (Zn-MOF), a carbon nanoflower CNF (Carbon Nano-Flower) and a graphitized carbon nanotube GCNT (Graphitized Carbon Nanotube) is modified on the surface of a glassy carbon electrode (GCE) to form a Zn-MOF@CNF@GCNT / GCE working electrode. Firstly, equal masses of CNF and GCNT were uniformly dispersed in N,N-dimethylformamide (DMF) solution by magnetic stirring under ultrasonic environment; then, a certain amount of Zn-MOF was added to the above solution, and a uniform suspension of Zn-MOF@CNF@GCNT mixture was obtained by ultrasonic dispersion; finally, the uniform suspension of Zn-MOF@CNF@GCNT mixture was drop-coated on the surface of GCE and dried under infrared lamp to obtain the working electrode Zn-MOF@CNF@GCNT / GCE modified with Zn-MOF@CNF@GCNT nanocomposite material.

[0027] In the present invention, the technical indicators of the zinc-based metal organic framework material (Zn-MOF) are as follows: particle size 100-400nm, composition Zn 2+ , C 4 H 5 N 2- , pore size 0.34~1.16nm, specific surface area ~1400m 2 / g. The technical indicators of carbon nanoflower (CNF) are as follows: black powder, size 700-800nm. The technical indicators of graphitized carbon nanotube (GCNT) are as follows: diameter 8-15nm, inner diameter 3-5nm, purity >99.9at%, length 10-50um.

[0028] The present invention is further described below with reference to specific embodiments.

[0029] Example 1

[0030] In this embodiment, a method for preparing a functionalized integrated carbon composite-based niclosamide electrochemical sensor comprises the following steps:

[0031] (1) Preparation of Zn-MOF@CNF@GCNT uniform suspension: 15 mg of equal mass of CNF (7.5 mg) and GCNT (7.5 mg) were added to 7.5 mL of N,N-dimethylformamide (DMF) solution, and continuous magnetic stirring (120 mins) was performed under ultrasonic environment to obtain a uniformly dispersed black CNF@GCNT suspension. Subsequently, a certain amount of Zn-MOF was added to the above suspension, the amount of Zn-MOF added was 15 mg, and ultrasonic dispersion (60 mins) was used again to mix evenly to obtain a uniformly mixed Zn-MOF@CNF@GCNT suspension.

[0032] (2) Preparation of Zn-MOF@CNF@GCNT / GCE working electrode: 5 μL of the above-mentioned Zn-MOF@CNF@GCNT uniform suspension was dropleted onto the pre-polished and cleaned GCE surface. The shape and size of the GCE were: CHI104 glassy carbon disk electrode diameter 3 mm, and dried under an infrared lamp for 6 mins to obtain a Zn-MOF@CNF@GCNT / GCE working electrode.

[0033] Among them, the thickness of Zn-MOF@CNF@GCNT nanocomposite on the GCE surface is 120 μm.

[0034] (3) Preparation of highly sensitive electrochemical sensor for detecting niclosamide: The above-mentioned Zn-MOF@CNF@GCNT / GCE working electrode, auxiliary electrode (platinum wire electrode) and reference electrode (saturated calomel electrode) were placed in a three-electrode glass electrolytic cell to form an electrochemical sensor for niclosamide detection. The detection limit can reach 7.68 nM, which has excellent electrochemical sensing detection performance for niclosamide.

[0035] The CV curves of the Zn-MOF@CNF@GCNT / GCE sensor prepared in this example and the unmodified sensor for detecting niclosamide are shown in Figure 1 ; The DPV curve of the prepared Zn-MOF@CNF@GCNT / GCE sensor for detecting niclosamide is shown in Figure 2 .

[0036] Depend on Figure 1It can be seen that the CV curves of these sensors detecting niclosamide all show an irreversible reduction peak and a pair of redox peaks. According to the electrochemical behavior of nitro compounds, the irreversible reduction peak of niclosamide can be attributed to the irreversible reduction of the nitro group to hydroxylamine, and the redox peak can be attributed to the reversible redox behavior of the hydroxylamine group. It should be noted that the CV peak current of the unmodified GCE sensor is weak. In contrast, the Zn-MOF@CNF@GCNT / GCE sensor presents a clear CV curve, which is closely related to the synergistic effect of the Zn-MOF@CNF@GCNT nanocomposite. The Zn-MOF used in the present invention is a zinc-based metal organic framework material with high thermal and chemical stability, high catalytic activity, large specific surface area and unique morphology, which can provide a large number of adsorption, reaction and active sites. The CNF used in the present invention is a carbon nanoflower, which is a new type of carbon-based material that looks like a flower and has a unique petal-like structure. This material is usually composed of carbon nanotubes, graphene or other carbon nanostructures, showing a unique petal-like or similar structure. It has the following advantages: (i) High specific surface area: carbon nanoflowers have a very high specific surface area due to their porous three-dimensional structure; (ii) Excellent electrical conductivity: carbon nanoflowers have good electrical conductivity, which helps to enhance the charge transport capacity of nanocomposites; (iii) Chemical stability: carbon nanoflowers have extremely high chemical stability and can maintain their performance under various environments; (iv) Unique morphology: the petal-like structure of carbon nanoflowers provides more active sites, which helps to promote electrochemical reactions. In addition, graphitized carbon nanotubes have excellent electrical conductivity. Graphitization can transform crystalline carbon into crystalline carbon, increase the proportion of sp2 hybridization between carbon atoms, and improve the mobility of electrons, thereby improving the electrical conductivity of carbon nanotubes. Because the arrangement of carbon atoms in the graphitization process is more orderly and the structural integrity of the tube wall is enhanced, graphitized carbon nanotubes have higher mechanical strength and toughness, as well as stronger chemical stability. In addition, graphitized carbon nanotubes have better adsorption properties due to their increased specific surface area and improved pore structure. The Zn-MOF@CNF@GCNT nanocomposite material used in the present invention can fully utilize the advantages of the above nanocomposite material, show a synergistic effect, and significantly improve the conductivity of the working electrode modified coating and the adsorption and enrichment capacity of niclosamide.

[0037] Depend on Figure 2It can be seen that the linear niclosamide concentration range of the DPV test of the Zn-MOF@CNF@GCNT / GCE sensor for detecting niclosamide is 0.01μM to 15μM. The research results show that the niclosamide concentration has a significant effect on the peak current response of the DPV curve. With the increase of niclosamide concentration, the peak current response of the DPV curve for detecting niclosamide gradually increases, and the two show a positive correlation. Based on the fitted linear relationship between the niclosamide concentration and the peak current response of the DPV curve, the linear regression equation of the response can be obtained, and then the detection limit of the prepared Zn-MOF@CNF@GCNT / GCE sensor for niclosamide is 7.68nM by calculation and analysis, indicating that the above-prepared sensor has excellent niclosamide sensing and detection performance.

[0038] Example 2

[0039] In this embodiment, a method for preparing a functionalized integrated carbon composite-based niclosamide electrochemical sensor comprises the following steps:

[0040] (1) Preparation of uniform Zn-MOF@CNF@GCNT suspension: 30 mg of equal mass of CNF (15 mg) and GCNT (15 mg) were added to 15 mL of N,N-dimethylformamide (DMF) solution, and continuous magnetic stirring (180 mins) was performed under ultrasonic environment to obtain a uniformly dispersed black Zn-MOF@GCNT suspension. Subsequently, a certain amount of Zn-MOF was added to the above suspension, the amount of Zn-MOF added was 30 mg, and ultrasonic dispersion (90 mins) was used again to mix evenly to obtain a uniformly mixed Zn-MOF@CNF@GCNT suspension.

[0041] (2) Preparation of GCNT@Zn-MOF / GCE working electrode: 5 μL of the above-mentioned Zn-MOF@CNF@GCNT uniform suspension was dropped onto the pre-polished and cleaned GCE surface. The shape and size of the GCE were: CHI104 glassy carbon disk electrode diameter 3 mm, and dried under an infrared lamp for 6 mins to obtain a Zn-MOF@CNF@GCNT / GCE working electrode.

[0042] Among them, the thickness of Zn-MOF@CNF@GCNT nanocomposite on the GCE surface is 160 μm.

[0043] (3) Preparation of highly sensitive electrochemical sensor for detecting niclosamide: The above-mentioned Zn-MOF@CNF@GCNT / GCE working electrode, auxiliary electrode (platinum wire electrode) and reference electrode (saturated calomel electrode) were placed in a three-electrode glass electrolytic cell to form an electrochemical sensor for niclosamide detection, which has excellent electrochemical sensing detection performance for niclosamide.

[0044] The implementation results show that the sensor prepared by the present invention has low cost, high efficiency, high sensitivity, small space occupation volume, easy to carry, and easy to realize outdoor field detection. Based on the synergistic effect of Zn-MOF, GCNT and CNF, the Zn-MOF@CNF@GCNT / GCE sensor has high sensitivity, low detection limit, and excellent niclosamide sensing detection performance.

[0045] The exemplary embodiments are chosen and described for the purpose of explaining certain principles of the invention and their practical applications, thereby enabling those skilled in the art to make and utilize various exemplary embodiments of the invention as well as various alternatives and modifications.

Claims

1. A functionalized integrated carbon composite-based niclosamide electrochemical sensor, characterized in that: Zn-MOF@CNF@GCNT nanocomposite materials prepared from zinc-based metal organic framework materials (Zn-MOF), carbon nanoflowers (CNF) and graphitized carbon nanotubes (GCNT) were modified on the surface of glassy carbon electrode (GCE) to form Zn-MOF@CNF@GCNT / GCE working electrode. The Zn-MOF@CNF@GCNT / GCE working electrode, auxiliary electrode and reference electrode were placed in an electrolytic cell to form a functionalized integrated carbon composite-based niclosamide electrochemical sensor.

2. The functionalized integrated carbon composite-based niclosamide electrochemical sensor according to claim 1, characterized in that: In the Zn-MOF@CNF@GCNT nanocomposite material, the content range of each component is as follows: the mass proportion of Zn-MOF is 30-50%, the mass proportion of CNF is 25-35%, and the mass proportion of GCNT is 25-35%.

3. The functionalized integrated carbon composite-based niclosamide electrochemical sensor according to claim 1, characterized in that: The thickness of Zn-MOF@CNF@GCNT nanocomposites on the GCE surface was 80-200 μm.

4. The method for preparing a functionalized integrated carbon composite-based niclosamide electrochemical sensor according to any one of claims 1 to 3, characterized in that: The following steps are involved: (1) Preparation of a uniform Zn-MOF@CNF@GCNT suspension: First, equal amounts of CNF and GCNT were added to a N,N-dimethylformamide (DMF) solution and continuously magnetically stirred under an ultrasonic environment to obtain a uniformly dispersed black CNF@GCNT suspension. Subsequently, a certain amount of Zn-MOF was added to the suspension, with the Zn-MOF addition ratio being 30-50% of the total mass of Zn-MOF, CNF and GCNT, and the mixture was dispersed and mixed uniformly under ultrasonic conditions again to obtain a uniformly mixed Zn-MOF@CNF@GCNT suspension. (2) Preparation of Zn-MOF@CNF@GCNT / GCE working electrode: The above-mentioned Zn-MOF@CNF@GCNT uniform suspension was drop-coated on the pre-polished GCE surface and dried under an infrared lamp to obtain a Zn-MOF@CNF@GCNT / GCE working electrode; (3) Preparation of an electrochemical sensor for highly sensitive detection of niclosamide: Using a platinum wire electrode as an auxiliary electrode and a saturated calomel electrode as a reference electrode, the above-mentioned Zn-MOF@CNF@GCNT / GCE working electrode, auxiliary electrode and reference electrode were placed in a three-electrode glass electrolytic cell to form a functionalized integrated carbon composite-based niclosamide electrochemical sensor.

5. The method for preparing a functionalized integrated carbon composite-based niclosamide electrochemical sensor according to claim 1, characterized in that: In the step (1), the ultrasonic dispersion time is 60 to 180 minutes, and the ultrasonic power is 180W.

6. The method for preparing a functionalized integrated carbon composite-based niclosamide electrochemical sensor according to claim 1, characterized in that: In the step (2), the infrared lamp drying time is 5 to 15 minutes.

7. The method for preparing a functionalized integrated carbon composite-based niclosamide electrochemical sensor according to claim 1, characterized in that: In the step (2), in order to construct the target working electrode, the surface of the glassy carbon electrode is pretreated by wet sand grinding, and the surface of the glassy carbon electrode is polished by ultrasonic cleaning to obtain a glassy carbon electrode with a clean surface and free of impurities.

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