Synthesis method of amino acid-based MOFs (Metal-Organic Frameworks) derived nano enzyme

Abstract

The invention discloses a synthesis method of an amino-acid-based MOFs (Metal-Organic Frameworks) derived nano-enzyme, and relates to the technical field of nano-enzyme synthesis, the synthesis method of the amino-acid-based MOFs derived nano-enzyme comprises the following steps: step 1, selecting proper metal ions and organic ligands; step 2, ultrasonic dispersion; step 3, precipitate drying; and step 4, activating treatment of the nano enzyme. The MOFs-derived nano-enzyme with alkaline phosphatase activity is synthesized by taking natural amino acid as a ligand and one of ions of zirconium, copper and iron as a metal node and introducing defects by a method of adding an acidic regulator in synthesis, and the crystal structure of the nano-enzyme is not changed under the introduction of the defects, so that the alkaline phosphatase activity of the MOFs-derived nano-enzyme is improved. The MOFs-derived nano-enzyme has the advantages that the MOFs-derived nano-enzyme is modified, the catalytic hydrolysis activity of the MOFs-derived nano-enzyme on phosphate substrates is greatly improved, good substrate specificity is shown, the structure of the MOFs-derived nano-enzyme does not change after long-term incubation under acidic, alkaline and high-temperature conditions, and compared with natural enzyme, the MOFs-derived nano-enzyme has good stability, pH stability and reusability.

Description

Technical Field

[0001] The present invention relates to the technical field of nanozyme synthesis, and in particular to a method for synthesizing an amino acid-based MOFs-derived nanozyme. Background Art

[0002] Nanozymes have made up for some of the shortcomings of natural enzymes with their high catalytic efficiency, good stability, good economy, and large-scale preparation. They have been widely used in various fields such as biosensors, disease diagnosis, immunoassay, and anti-cancer treatment. Among them, metal-organic framework materials (MOF) are an important branch of nanozyme materials.

[0003] The existing technology has the following problems:

[0004] Existing nanozymes are not stable enough and are costly. Nanozymes from different sources vary greatly in molecular weight, coding sequence, spatial structure and catalytic function. Summary of the invention

[0005] The present invention provides a method for synthesizing amino acid-based MOFs-derived nanozymes to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A method for synthesizing an amino acid-based MOFs-derived nanozyme, the method comprising the following steps:

[0008] Step 1: Select appropriate metal ions and organic ligands;

[0009] Step 2: Ultrasonic dispersion;

[0010] Step 3: precipitation and drying;

[0011] Step 4: Activation treatment of nanozymes.

[0012] A further improvement of the technical solution of the present invention is that: in the step 1, natural amino acids are used as ligands, and the basic framework metal ions constituting MOF are one of metal cerium zirconium, metal cerium copper, and metal cerium iron.

[0013] A further improvement of the technical solution of the present invention is that: in the step 2, 2.8 g of amino acids are poured into a beaker, and then 5 ml of water is added to the beaker, and then the beaker is placed in an ultrasonic disperser to disperse the amino acids, and then 2.33 g of metal ion powder is added to the suspension, and a colorless transparent solution is obtained after ultrasonic dispersion, and then 5 ml of water is added to rinse the inner wall of the beaker, thereby flushing the metal ion powder into the solution.

[0014] A further improvement of the technical solution of the present invention is that in the step three, 0-10 ml of acetic acid, an acidic regulator, is added to the inside of the beaker, and after a hydrothermal reaction at 120° C., it is refluxed for 10 hours. After the suspension is cooled to room temperature, the precipitate is collected by a centrifuge, and washed with ultrapure water and ethanol 3 times each. After the precipitation is completed, it is transferred to a vacuum drying oven and dried at 60° C. for 24 hours.

[0015] A further improvement of the technical solution of the present invention is that: in the step four, HCl is used for activation treatment, by weighing 20 mg of the dried powder and adding it to 20 ml of 0.01M HCl solution, leaving it at room temperature for 12 hours, centrifuging it in a centrifuge, washing it with ultrapure water for 3 times, transferring it to a vacuum drying oven after precipitation, and drying it at 60°C for 24 hours to complete the synthesis of MOFs nanozyme.

[0016] Due to the adoption of the above technical solution, the present invention has the following technical advances compared with the prior art:

[0017] 1. The present invention provides a method for synthesizing amino acid-based MOFs-derived nanozymes, which use natural amino acids as ligands and one of zirconium, copper, and iron ions as metal nodes. Defects are introduced by adding an acidic regulator during the synthesis to synthesize MOFs-derived nanozymes with alkaline phosphatase activity. The introduction of defects does not change the crystal structure of the nanozyme, but greatly improves its catalytic hydrolysis activity for phosphate substrates, showing good substrate specificity. The MOFs-derived nanozyme does not change its structure under long-term incubation under acidic, alkaline and high temperature conditions, and has good stability, pH stability and reusability compared to natural enzymes. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The figure is a flow chart of the synthesis of amino acid-based MOFs-derived nanozymes of the present invention. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below in conjunction with embodiments:

[0020] Example 1

[0021] like Figure 1 As shown, the present invention provides a method for synthesizing an amino acid-based MOFs-derived nanozyme, and the method for synthesizing an amino acid-based MOFs-derived nanozyme comprises the following steps:

[0022] Step 1: Select appropriate metal ions and organic ligands;

[0023] Step 2: Ultrasonic dispersion;

[0024] Step 3: precipitation and drying;

[0025] Step 4: Activation treatment of nanozymes.

[0026] In step 1, natural amino acids are used as ligands, and the basic framework metal ions constituting MOF are one of metal cerium zirconium, metal cerium copper, and metal cerium iron.

[0027] In step 2, 2.8 g of amino acids are poured into a beaker, and then 5 ml of water is added to the beaker. The beaker is then placed in an ultrasonic disperser to disperse the amino acids. 2.33 g of metal ion powder is then added to the suspension. After ultrasonic dispersion, a colorless and transparent solution is obtained. 5 ml of water is then added to rinse the inner wall of the beaker, thereby flushing the metal ion powder into the solution.

[0028] In step three, 0-10 ml of acidic regulator acetic acid is added to the inside of the beaker. After a hydrothermal reaction at 120°C, it is refluxed for 10 hours. After the suspension is cooled to room temperature, the precipitate is collected by a centrifuge and washed with ultrapure water and ethanol three times each. After the precipitation is completed, it is transferred to a vacuum drying oven and dried at 60°C for 24 hours.

[0029] In step 4, HCl is used for activation treatment. 20 mg of the dried powder is weighed and added to 20 ml of 0.01 M HCl solution, and the mixture is placed at room temperature for 12 hours. After centrifugation in a centrifuge, the mixture is washed three times with ultrapure water. After precipitation, the mixture is transferred to a vacuum drying oven and dried at 60°C for 24 hours to complete the synthesis of MOFs nanozyme.

[0030] In this embodiment, natural amino acids are used as ligands and one of the ions of zirconium, copper, and iron is used as a metal node. Defects are introduced by adding an acidic regulator during the synthesis to synthesize a MOFs-derived nanozyme with alkaline phosphatase activity. The introduction of defects does not change the crystal structure of the nanozyme, but greatly improves its catalytic hydrolysis activity for phosphate substrates, showing good substrate specificity. The structure of the MOFs-derived nanozyme does not change under long-term incubation under acidic, alkaline and high temperature conditions, and has good stability, pH stability and reusability compared to natural enzymes.

[0031] The above generally describes the present invention in detail, but it is obvious to a person skilled in the art that some modifications or improvements can be made to the present invention. Therefore, modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. A method for synthesizing amino acid-based MOFs-derived nanozymes, characterized in that: The amino acid-based MOFs-derived nanozyme synthesis method comprises the following steps: Step 1: Select appropriate metal ions and organic ligands; Step 2: Ultrasonic dispersion; Step 3: precipitation and drying; Step 4: Activation treatment of nanozymes.

2. The method for synthesizing an amino acid-based MOFs-derived nanozyme according to claim 1, characterized in that: In the step 1, natural amino acids are used as ligands, and the basic framework metal ions constituting the MOF are one of metal cerium zirconium, metal cerium copper, and metal cerium iron.

3. The method for synthesizing an amino acid-based MOFs-derived nanozyme according to claim 1, characterized in that: In the step 2, 2.8 g of amino acid is poured into a beaker, and then 5 ml of water is added to the beaker. The beaker is then placed in an ultrasonic disperser to disperse the amino acid. 2.33 g of metal ion powder is then added to the suspension to obtain a colorless transparent solution after ultrasonic dispersion. 5 ml of water is then added to rinse the inner wall of the beaker, thereby rinsing the metal ion powder into the solution.

4. The method for synthesizing an amino acid-based MOFs-derived nanozyme according to claim 1, characterized in that: In the step three, 0-10 ml of acetic acid, an acidic regulator, is added to the inside of the beaker. After a hydrothermal reaction at 120° C., the mixture is refluxed for 10 hours. After the suspension is cooled to room temperature, the precipitate is collected by a centrifuge and washed three times with ultrapure water and ethanol respectively. After the precipitation is completed, the mixture is transferred to a vacuum drying oven and dried at 60° C. for 24 hours.

5. The method for synthesizing an amino acid-based MOFs-derived nanozyme according to claim 1, characterized in that: In the step 4, HCI is used for activation treatment. 20 mg of the dried powder is weighed and added to 20 ml of 0.01 M HCI solution, and the mixture is placed at room temperature for 12 hours. After centrifugation in a centrifuge, the mixture is washed three times with ultrapure water. After precipitation, the mixture is transferred to a vacuum drying oven and dried at 60° C. for 24 hours to complete the synthesis of MOFs nanozyme.

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