Preparation method of rhein-metal organic framework composite antibacterial material

Abstract

The invention relates to preparation and application of a novel antibacterial material, in particular to a novel rhein metal organic framework composite antibacterial material formed by coordination of rhein and a metal organic framework structure. The invention belongs to the field of nano antibacterial materials. The preparation method has the advantages that the organic-inorganic hybrid material with highly ordered intramolecular voids is formed by coordinating metal atom zinc with phenolic hydroxyl groups at the positions 1 and 8 and carbonyl groups at the position 9 in rhein and 2-methylimidazole by adopting a one-step method; through coordination of rhein, metal atoms and organic solvents, the stability of rhein is improved, and the hydrophilic performance of rhein is improved.

Description

Technical Field

[0001] The present invention relates to the preparation and application of a novel antibacterial material. In particular, it relates to a method for preparing a rhein-metal organic framework composite antibacterial material. Specifically, it relates to a novel rhein metal organic framework composite antibacterial material formed by the coordination of rhein and a metal organic framework structure. The present invention belongs to the field of nano antibacterial materials. Background Art

[0002] Rhein is commonly found in traditional Chinese medicines such as rhubarb, Polygonum multiflorum, and Polygonum cuspidatum. It is a monoanthracene 1,8-dihydroxyanthrone derivative. Rhein has antibacterial, anti-inflammatory, blood stasis, antioxidant and anti-cancer pharmacological effects, so it has a wide range of uses. Among them, rhein has significant antibacterial activity and has significant inhibitory effects on Staphylococcus, Streptococcus, Diphtheria Corynebacterium, Bacillus subtilis, Salmonella typhi, Shigella dysenteriae, etc. However, rhein has poor water solubility and is easily soluble in organic solvents or alkaline solutions, which significantly limits its application.

[0003] Metal-organic frameworks (MOFs) are a type of crystalline porous materials with a periodic network structure formed by the self-assembly of inorganic metal centers (metal ions or metal clusters) and organic ligands. MOFs materials have the advantages of large specific surface area, good biocompatibility, stable chemical and physical properties, and biodegradability. Rhein is an anthraquinone compound containing α-phenolic hydroxyl groups, in which the phenolic hydroxyl groups at positions 1,8 and the carbonyl group at position 9 are suitable for coordination with various metal ions. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide a method for preparing a rhein-metal organic framework composite antibacterial material.

[0005] Another object of the present invention is to provide a product obtained by the above method.

[0006] The object of the present invention is achieved by the following scheme: a method for preparing a rhein-metal organic framework composite antibacterial material, wherein rhein is coordinated with a metal organic framework structure to form a novel rhein metal organic framework composite antibacterial material, comprising the following steps: 1) Weigh 1-3 g zinc nitrate hexahydrate and add it to 20 mL methanol solution. Stir well at room temperature and set aside for use. 2) Dissolve 0.1~1g of rhein in 2mL of chloroform solution, add 10mL of methanol solution, stir at room temperature for 30min until fully dissolved and set aside for use; 3) Dissolve 3-6 g 2-methylimidazole in 20 mL methanol solution and stir thoroughly at room temperature for later use; 4) After the solution of step 2) and the solution of step 3) are evenly mixed, they are quickly transferred to the solution of step 1) and stirred at room temperature for 1 hour at a stirring speed of 400 rpm / min. The solution gradually changes from colorless and transparent to a dark yellow solution and is aged at room temperature for 24 hours; 5) Transfer the solution in step 4) to a centrifuge tube, centrifuge at 5000 rpm / min for 10 min, discard the supernatant, repeat the above steps with ultrapure water and methanol for 3 to 5 times, and place the precipitate in a vacuum drying oven at 50°C for overnight drying to obtain R@Zn-MOFs antibacterial material.

[0007] The present invention also provides a R@Zn-MOFs nanoparticle product obtained by the above method, wherein the R@Zn-MOFs nanoparticle has a size of 300-600 nm.

[0008] The pore size of the R@Zn-MOFs nanoparticles described in the present invention is 5-20 nm.

[0009] The present invention adopts MOFs to coordinate with rhein to improve the water solubility of rhein, forming a stable antibacterial material, which has high research significance and application value.

[0010] In the technical solution of the present invention, the metal atom zinc is coordinated with the 1,8-position phenolic hydroxyl group and the 9-position carbonyl group in rhein and 2-methylimidazole to form an organic-inorganic hybrid material with highly ordered intramolecular voids. By adjusting the amount of rhein, 2-methylimidazole and zinc acetate, the particle size and porosity of the MOF structure can be further adjusted to obtain MOF structures with different morphologies.

[0011] An antibacterial material of rhein-MOFs (R@Zn-MOFs) improves the water solubility of rhein itself, thereby achieving the purpose of preparing an antibacterial material with good dispersibility and stability.

[0012] The advantages of the present invention are: (1) An organic-inorganic hybrid material with highly ordered intramolecular voids was formed by coordinating the metal atom zinc with the 1,8-phenolic hydroxyl group and the 9-carbonyl group in rhein and 2-methylimidazole in a one-step method.

[0013] (2) The coordination effect between rhein and metal atoms and organic solvents increases the stability of rhein and improves its hydrophilic properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is the TEM image of R@Zn-MOFs prepared in Example 1. DETAILED DESCRIPTION

[0015] The technical scheme of the present invention is further described below through specific examples. The following examples are further explanations of the present invention, but do not limit the scope of the present invention.

[0016] Example 1 A rhein-metal organic framework composite R@Zn-MOFs antibacterial material is prepared by the following steps: 1) Weigh 1.65 g zinc nitrate hexahydrate and add it to 20 mL methanol solution. Stir well at room temperature and set aside for use; 2) Dissolve 0.4 g of rhein in 2 mL of chloroform solution, add 10 mL of methanol solution, stir at room temperature for 30 min until fully dissolved and set aside; 3) Dissolve 4 g of 2-methylimidazole in 20 mL of methanol solution and stir thoroughly at room temperature for later use; 4) After the solution of step 2) and the solution of step 3) are evenly mixed, the mixture is quickly transferred to the solution of step 1), and stirred at room temperature for 1 hour at a stirring speed of 400 rpm / min. The solution gradually changes from colorless and transparent to a dark yellow solution, and is aged at room temperature for 24 hours to obtain a solution; 5) Transfer the solution in step 4) to a centrifuge tube, centrifuge at 5000 rpm / min for 10 min, discard the supernatant, repeat the above steps with ultrapure water and methanol for 3 to 5 times, and place the precipitate in a vacuum drying oven at 50°C and dry overnight to obtain the R@Zn-MOFs antibacterial material.

[0017] Figure 1 This is the TEM image of R@Zn-MOFs prepared in this example. Figure 1 It can be seen that the size of R@Zn-MOFs antibacterial material is 500 nm.

[0018] Example 2 R@Zn-MOFs antibacterial material was prepared according to the following steps: 1) Weigh 1.5 g zinc nitrate hexahydrate and add it to 20 mL methanol solution. Stir thoroughly at room temperature and set aside for use. 2) Dissolve 0.6 g of rhein in 2 mL of chloroform solution, add 10 mL of methanol solution, stir at room temperature for 30 min until fully dissolved and set aside; 3) Dissolve 5 g of 2-methylimidazole in 20 mL of methanol solution and stir thoroughly at room temperature for later use; 4) After the solution of step 2) and the solution of step 3) are evenly mixed, they are quickly transferred to the solution of step 1) and stirred at room temperature for 1 hour at a stirring speed of 400 rpm / min. The solution gradually changes from colorless and transparent to a dark yellow solution and is aged at room temperature for 24 hours; 5) Transfer the solution in step 4) to a centrifuge tube, centrifuge at 5000 rpm / min for 10 min, discard the supernatant, repeat the above steps with ultrapure water and methanol for 3 to 5 times, and place the precipitate in a vacuum drying oven at 50°C for overnight drying to obtain R@Zn-MOFs antibacterial material.

[0019] Example 3 R@Zn-MOFs antibacterial material was prepared according to the following steps: 1) Weigh 1.2 g zinc nitrate hexahydrate and add it to 20 mL methanol solution. Stir thoroughly at room temperature and set aside for use. 2) Dissolve 0.5 g of rhein in 2 mL of chloroform solution, add 10 mL of methanol solution, stir at room temperature for 30 min until fully dissolved and set aside; 3) Dissolve 6 g of 2-methylimidazole in 20 mL of methanol solution and stir thoroughly at room temperature for later use; 4) After the solution of step 2) and the solution of step 3) are evenly mixed, they are quickly transferred to the solution of step 1) and stirred at room temperature for 1 hour at a stirring speed of 400 rpm / min. The solution gradually changes from colorless and transparent to a dark yellow solution and is aged at room temperature for 24 hours; 5) Transfer the solution in step 4) to a centrifuge tube, centrifuge at 5000 rpm / min for 10 min, discard the supernatant, repeat the above steps with ultrapure water and methanol for 3 to 5 times, and place the precipitate in a vacuum drying oven at 50°C for overnight drying to obtain R@Zn-MOFs antibacterial material.

[0020] Antibacterial performance test: Staphylococcus aureus was used as the test strain. Staphylococcus aureus cultured for more than three generations was diluted to about 10 5 cfu / mL, and a pre-made bacterial suspension was obtained; Experimental group: 0.25 g of the R@Zn-MOFs particles prepared in Example 1-3 were placed in a conical flask, 45 mL of PBS containing 0.1% Tween-80 was added and mixed, and then 2.5 mL of the above-mentioned pre-made bacterial suspension was added.

[0021] Control group: A bacterial suspension of Zn-MOFs particles without rhein was prepared according to the above method.

[0022] The test group and the control group were placed in a 37°C 100 rpm constant temperature shaker for 2 hours. After the shaking, the test group and the control group were appropriately diluted and inoculated on a plate containing agar medium. Three parallel samples were set for each concentration. The plates were incubated in a 37°C incubator for 24 hours, and the colonies were counted. As shown in Figure 1, the R@Zn-MOFs antibacterial materials obtained in Examples 1 to 3 of the present invention have excellent antibacterial properties. 。

Claims

1. A method for preparing a rhein-metal organic framework composite antibacterial material, characterized in that , rhein is coordinated with the metal organic framework structure to form a rhein-metal organic framework composite structure, including the following steps: 1) Weigh 1-3 g zinc nitrate hexahydrate and add it to 20 mL methanol solution. Stir well at room temperature and set aside for use. 2) Dissolve 0.1~1g of rhein in 2mL of chloroform solution, add 10mL of methanol solution, stir at room temperature for 30min until fully dissolved and set aside for use; 3) Dissolve 3-6 g 2-methylimidazole in 20 mL methanol solution and stir thoroughly at room temperature for later use; 4) After the solution of step 2) and the solution of step 3) are evenly mixed, the mixture is quickly transferred to the solution of step 1), and stirred at room temperature for 1 hour at a stirring speed of 400 rpm / min. The solution gradually changes from colorless and transparent to a dark yellow solution, and is aged at room temperature for 24 hours to obtain a solution; 5) Transfer the solution in step 4) to a centrifuge tube, centrifuge at 5000 rpm / min for 10 min, discard the supernatant, repeat the above steps with ultrapure water and methanol for alternating centrifugation 3 to 5 times, place the obtained precipitate in a vacuum drying oven at 50°C and dry overnight, and the R@Zn-MOFs antibacterial material can be obtained.

2. The method for preparing the rhein-metal organic framework composite antibacterial material according to claim 1, characterized in that: Prepare as follows: 1) Weigh 1.65 g zinc nitrate hexahydrate and add it to 20 mL methanol solution. Stir well at room temperature and set aside for use; 2) Dissolve 0.4 g of rhein in 2 mL of chloroform solution, add 10 mL of methanol solution, stir at room temperature for 30 min until fully dissolved and set aside; 3) Dissolve 4 g of 2-methylimidazole in 20 mL of methanol solution and stir thoroughly at room temperature for later use; 4) After the solution of step 2) and the solution of step 3) are evenly mixed, the mixture is quickly transferred to the solution of step 1), and stirred at room temperature for 1 hour at a stirring speed of 400 rpm / min. The solution gradually changes from colorless and transparent to a dark yellow solution, and is aged at room temperature for 24 hours to obtain a solution; 5) Transfer the solution in step 4) to a centrifuge tube, centrifuge at 5000 rpm / min for 10 min, discard the supernatant, repeat the above steps with ultrapure water and methanol for 3 to 5 times, and place the precipitate in a vacuum drying oven at 50°C and dry overnight to obtain the R@Zn-MOFs antibacterial material.

3. The method for preparing the rhein-metal organic framework composite antibacterial material according to claim 1, characterized in that: Prepare according to the following steps: 1) Weigh 1.5 g zinc nitrate hexahydrate and add it to 20 mL methanol solution, stir well at room temperature and set aside; 2) Dissolve 0.6 g of rhein in 2 mL of chloroform solution, add 10 mL of methanol solution, stir at room temperature for 30 min until fully dissolved and set aside; 3) Dissolve 5 g of 2-methylimidazole in 20 mL of methanol solution and stir thoroughly at room temperature for later use; 4) After the solution of step 2) and the solution of step 3) are evenly mixed, they are quickly transferred to the solution of step 1) and stirred at room temperature for 1 hour at a stirring speed of 400 rpm / min. The solution gradually changes from colorless and transparent to a dark yellow solution and is aged at room temperature for 24 hours; 5) Transfer the solution in step 4) to a centrifuge tube, centrifuge at 5000 rpm / min for 10 min, discard the supernatant, repeat the above steps with ultrapure water and methanol for 3 to 5 times, and place the precipitate in a vacuum drying oven at 50°C for overnight drying to obtain R@Zn-MOFs antibacterial material.

4. The method for preparing the rhein-metal organic framework composite antibacterial material according to claim 1, characterized in that: Prepare as follows: 1) Weigh 1.2 g zinc nitrate hexahydrate and add it to 20 mL methanol solution. Stir thoroughly at room temperature and set aside for use. 2) Dissolve 0.5 g of rhein in 2 mL of chloroform solution, add 10 mL of methanol solution, stir at room temperature for 30 min until fully dissolved and set aside; 3) Dissolve 6 g of 2-methylimidazole in 20 mL of methanol solution and stir thoroughly at room temperature for later use; 4) After the solution of step 2) and the solution of step 3) are evenly mixed, they are quickly transferred to the solution of step 1) and stirred at room temperature for 1 hour at a stirring speed of 400 rpm / min. The solution gradually changes from colorless and transparent to a dark yellow solution and is aged at room temperature for 24 hours; 5) Transfer the solution in step 4) to a centrifuge tube, centrifuge at 5000 rpm / min for 10 min, discard the supernatant, repeat the above steps with ultrapure water and methanol for 3 to 5 times, and place the precipitate in a vacuum drying oven at 50°C for overnight drying to obtain R@Zn-MOFs antibacterial material.

5. A rhein-metal organic framework composite antibacterial material, obtained according to the preparation method according to any one of claims 1 to 4, wherein the R@Zn-MOFs nanoparticle size is 300-600 nm.

6. The rhein-metal organic framework composite antibacterial material according to claim 5, characterized in that: The pore size of the R@Zn-MOFs nanoparticles is between 5 and 20 nm.

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