阅读说明：本技术 铜基三维金属有机框架材料在仿酶上的应用 (Application of copper-based three-dimensional metal organic framework material in enzyme simulation ) 是由 单丹 刘子萱 于 2019-08-30 设计创作，主要内容包括：本发明公开了一种铜基三维金属有机框架材料在仿酶上的应用,所述有机框架材料为Cu-MOF,其可作为生物模拟酶传感器对H<Sub>2</Sub>O<Sub>2</Sub>检测。对Cu-MOF进行电催化试验,发现该材料可以在模拟人体的中性酸碱pH条件下,催化过氧化氢,并具有较强的催化效果。(The invention discloses application of a copper-based three-dimensional metal organic framework material in enzyme simulation, wherein the organic framework material is Cu-MOF and can be used as a biological mimic enzyme sensor to H 2 O 2 And (6) detecting. An electrocatalysis test is carried out on Cu-MOF, and the material is found to be capable of catalyzing hydrogen peroxide under the condition of neutral acid-base pH of a simulated human body and has a strong catalysis effect.)

1. Cu-MOF (metal organic framework) made of copper-based three-dimensional metal organic framework materialIs a bio-mimetic enzyme sensor pair H₂O₂The use of detection.

2. Use according to claim 1, wherein the Cu-MOF is prepared by: dissolving polyvinylpyrrolidone in mixed solution of DMF and ethanol, performing ultrasonic treatment for 30 + -5 min to obtain solution A, and mixing Cu (NO)₃)₂·3(H₂O) and 2-amino terephthalic acid are added into DMF to obtain a solution B, the solution A and the solution B are mixed, ultrasonic treatment is carried out for 30 plus or minus 5min, the reaction is carried out for 8 plus or minus 1h at the temperature of 120 plus or minus 5 ℃, and the Cu-MOF is obtained after filtration, centrifugation and vacuum drying.

3. The use according to claim 2, wherein the volume ratio of DMF to ethanol in the mixed solution of DMF and ethanol is 1: 1.

4. Use according to claim 2, characterized in that Cu (NO)₃)₂·3(H₂O) and 2-aminoterephthalic acid in a molar ratio of 10: 3.

5. Use according to claim 2, characterized in that polyvinylpyrrolidone is mixed with Cu (NO)₃)₂·3(H₂O) in a mass ratio of 13: 1.

Technical Field

The invention belongs to the technical field of preparation of biological mimic enzyme sensors, and relates to application of a copper-based three-dimensional metal organic framework.

Background

In the field of biotechnology, hydrogen peroxide (H) can be rapidly and accurately determined₂O₂) In order to develop a hydrogen peroxide sensor having high sensitivity, excellent selectivity and good accuracy, various methods have been used. In the last decades, electrochemical biosensors based on natural enzymes have been increasingly studied due to their high sensitivity and excellent selectivity. However, based on natural enzymesThe electrochemical biosensors of (a) are generally complex, expensive and very dependent on the external pH and temperature. Therefore, constructing mimic enzyme biosensors is the focus of current research. Recently, transition metals, transition metal oxides or hydroxides, and carbon-based materials have been extensively studied as active materials for peroxidase mimetic enzyme sensors. However, their application is limited by low toxicity resistance, poor operational stability or limited electron conductivity, and in order to solve these problems, H having high performance was developed₂O₂Novel materials for detection are indispensable.

Because of the inherent disadvantages of natural peroxidase, such as limited source, difficulty in purification, poor stability, large molecular weight, and short in vivo half-life, the development of a number of peroxide mimetic enzymes has been chosen to replace the natural enzymes. At present, there are several types of peroxide mimic enzyme researches, the first type is a peroxide mimic enzyme containing iron porphyrin, and the mimic enzyme overcomes the defects that hydrogen peroxide is easy to decompose and accumulate in water, but the mimic enzyme is expensive, difficult to synthesize and low in neutral cost ratio in actual production. The second type is a selenium-containing peroxide mimic enzyme which has hydrogen peroxide catalytic performance, but lacks effective connecting functional groups, has low activity, weak electron transfer capability and general catalytic performance. The third type is MOF type, namely organic metal framework type mimic enzyme, which is generally simple to synthesize and has excellent catalytic performance, and the catalytic performance and the active center of the mimic enzyme are different to a certain extent according to different metal sites.

Disclosure of Invention

Aiming at the defects of high price, poor electronic transmission performance and general catalytic performance of the existing peroxide mimic enzyme material, the invention provides a peroxide mimic enzyme material based on a copper-based three-dimensional metal organic framework, which has divalent active sites of cuprous and cupric, can efficiently catalyze hydrogen peroxide and has strong electronic transmission capacity.

The technical scheme of the invention is as follows:

the copper-based three-dimensional metal organic framework material can be used as a biological mimic enzyme sensor pair H₂O₂And detecting, wherein the copper-based three-dimensional metal organic framework material is Cu-MOF.

Further, the Cu-MOF is prepared by the following steps: dissolving polyvinylpyrrolidone (PVP) in mixed solution of DMF (N, N-dimethylformamide) and ethanol, performing ultrasonic treatment for 30 + -5 min to obtain solution A, and mixing Cu (NO)₃)₂·3(H₂O) (copper nitrate trihydrate) and NH₂Adding BTC (2-amino terephthalic acid) into DMF to obtain a solution B, mixing the solution A and the solution B, carrying out ultrasonic treatment for 30 +/-5 min, reacting for 8 +/-1 h at the temperature of 120 +/-5 ℃, filtering, centrifuging, and drying in vacuum to obtain the Cu-MOF.

Furthermore, the volume ratio of DMF to ethanol in the mixed solution of DMF and ethanol is 1: 1.

Further, Cu (NO)₃)₂·3(H₂O) and NH₂-a molar ratio of BTC of 10: 3.

Further, polyvinylpyrrolidone and Cu (NO)₃)₂·3(H₂O) in a mass ratio of 13: 1.

Compared with the prior art, the invention has the following remarkable effects:

(1) the invention controls the synthesis state and the morphology of the MOFs by adding polyvinylpyrrolidone with different proportions, and controls the size of the MOFs within a nanometer range, so that the material has the best catalytic performance.

(2) XRD and infrared tests are carried out on the PVP, and the PVP is found not to participate in the formation of the Cu-MOFs, but can be used as a template to regulate the morphology and the size of the PVP.

(3) The electro-catalysis test shows that the material can catalyze hydrogen peroxide under the condition of neutral acid-base pH of a simulated human body and has strong catalysis effect.

Drawings

FIG. 1 is a scanning electron microscope image of Cu-MOF formed under different ratios of PVP.

FIG. 2 is a graph of infrared and X-ray diffraction spectra of Cu-MOF and Cu-MOFs.

FIG. 3 is a cyclic voltammogram of Cu-MOF formed under different ratios of PVP.

FIG. 4 is a cyclic voltammogram of Cu-MOFs catalyzing hydrogen peroxide.

FIG. 5 is a cyclic voltammogram of different scanning speeds of Cu-MOFs.

FIG. 6 is a linear scanning voltammogram of catalytic hydrogen peroxide by Cu-MOFs.

FIG. 7 is a cyclic voltammogram of Cu-MOFs under different pH conditions.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described in further detail with reference to the following examples and accompanying drawings.

The invention aims to synthesize Cu-MOF for regulating and controlling the size and the shape by utilizing polyvinylpyrrolidone (PVP), and the nanometer MOF has a new three-dimensional structure and better electronic transmission capability through coordination of metal and carboxyl and the action of a surfactant special for the polyvinylpyrrolidone. Based on the application of the existing Cu-MOF in the photoelectric field, the inventor utilizes polyvinylpyrrolidone to perform size control so as to enable the material to have the optimal catalytic performance.

Therefore, the following embodiments synthesize the three-dimensional material through coordination, and simultaneously add different proportions of PVP to seek a three-dimensional metal organic framework material which has stable structure, strong electron transmission capability and strong catalytic capability for hydrogen peroxide, and the new three-dimensional organic metal framework can have strong catalytic effect on the hydrogen peroxide, thereby being used as a peroxide mimic enzyme material to construct a biosensor.

The obtained product is sealed and stored at 25 +/-5 ℃, and then is subjected to SEM (scanning electron microscope), TEM (projection electron microscope), XRD (X-ray diffraction spectrum) and XPS (X-ray photoelectron spectroscopy) characterization.

The invention also relates to a method for preparing the product by the method that 1: 200 are prepared into water solution for electrochemical test.

In the invention, the catalytic performance of the material is measured according to the following method:

using an electrochemical test method, according to a general electrochemical test method, glassy carbon electrodes with a diameter of 3mm are coated with gamma-Al of 0.3 and 0.05 mu m in sequence₂O₃Polishing the chamois leather of the saturated aqueous solution, then carrying out ultrasonic cleaning by using ultrapure water and ethanol in sequence, and finally blowing and drying by using nitrogen.

The method comprises the following specific steps: the product obtained was as follows 5: 200 to obtain a catalyst solution with the concentration of 5 mg/mL. 10 mu L of the evenly mixed catalyst solution is carefully dripped on the surface of the polished glassy carbon electrode and dried at room temperature. After natural drying, before electrochemical test, 10 μ L of 5% naphthol 117 ethanol solution is dripped on the surface of the electrode for sealing, and the electrode is dried at room temperature. The electrolyte solution was turned on half an hour N before testing₂The gas is brought to saturation concentration. Finally, the electrodes were soaked in the electrolyte for 30min before electrochemical measurements. Electrochemical testing used a model CHI660D electrochemical workstation, with auxiliary and reference electrodes being 2mm platinum wire and saturated calomel electrodes, respectively.