A silver-based antibacterial material and its preparation method and application

Abstract

The present invention discloses a silver-based antimicrobial material, its preparation method, and its application. First, a treatment agent for the synthesis of Ag-MOF materials is provided, comprising raw materials: a cationic surfactant, an oxidant, and a complex. When a silver substrate is immersed in this treatment agent, a well-organized Ag-MOF crystal material is formed. The Ag-MOF material exhibits high antimicrobial activity and water disinfection capabilities, establishing a rapid, gentle, convenient, and efficient water disinfection method.

Description

Technical Field

[0001] The present invention belongs to the field of silver-based antibacterial materials, and in particular relates to a silver-based antibacterial material, a preparation method thereof, and an application thereof. Background Art

[0002] Today, at least one-sixth of the world's population still lacks access to safe drinking water. Pathogen-contaminated water poses a significant threat to human health, resulting in millions of deaths annually. Therefore, there is an urgent need to develop efficient and simple methods to eliminate pathogenic microorganisms in water. Commonly used methods include chlorine-based chemicals, ultraviolet disinfection, and ozone treatment. However, these conventional methods have significant drawbacks: chlorine-based chemicals produce carcinogenic disinfection byproducts; ozone disinfection also produces disinfection byproducts and has high equipment costs; and ultraviolet disinfection requires high energy consumption and can cause bacterial reactivation. Newly developed membrane separation technologies demonstrate high water disinfection efficiency, but due to unavoidable long-term contact with microorganisms, they gradually lose their bactericidal ability and also pose the problem of biofouling. Given this situation, there is an urgent need to develop new, simpler, cheaper, safer, and more effective methods for disinfecting microbially contaminated water from source to point of use.

[0003] The rapid development of nanotechnology has stimulated significant interest in its applications across various fields. In recent years, carbon nanotubes and metal nanoparticles have been used for water disinfection due to their unique advantages in electrical conductivity, photocatalytic activity, bactericidal capacity, and low toxicity. Silver nanoparticles, in particular, have attracted considerable attention due to their unique physicochemical properties and broad-spectrum antimicrobial activity. While their antimicrobial mechanism remains uncertain, it is hypothesized to involve three key factors: the release of silver ions, direct contact and disruption of microbial membranes by the silver nanoparticles themselves, and the generation of reactive oxygen species. For water disinfection, most researchers have approached loading silver nanoparticles onto various organic or inorganic substrates to control their contact and release during bacterial interaction. While the effectiveness of silver nanomaterials in water disinfection applications has been well-documented, they also have several limitations. For example, loading silver nanoparticles onto filtration substrates often requires complex synthesis methods, sometimes requiring electrical energy. Furthermore, compared to silver ions, silver nanoparticles are relatively toxic. Therefore, a simple and safe strategy is needed to construct silver-based antimicrobial materials for water disinfection.

[0004] Silver-based metal-organic frameworks (Ag-MOFs) are formed by silver ions and organic ligands and have attracted much attention as a new antibacterial material. They combine the biocompatibility of organic ligands with the excellent antibacterial properties of silver ions, effectively improving the stability of silver ions. Silver ions can also be released continuously, avoiding the acute toxicity caused by sudden release. However, the synthesis conditions of the currently reported Ag-MOF materials are complex and harsh. Based on this, the present invention develops an Ag-MOF material and a mild and rapid synthesis method thereof. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention first provides an Ag-MOF material synthesis treatment agent, which comprises raw materials: a cationic surfactant, an oxidant and a complex;

[0006] The cationic surfactant is selected from a quaternary ammonium salt, and the alkyl group in the quaternary ammonium salt is selected from an alkyl chain with a carbon number of not less than 8, such as an alkyl chain with a carbon number of 8 to 20. Exemplarily, the alkyl group is selected from an alkyl chain with a carbon number of 12, 14 or 16;

[0007] The oxidant is a persulfate, for example, one or more selected from ammonium persulfate, potassium persulfate and sodium hydrogen persulfate;

[0008] The complex is selected from one or more of cysteine ​​hydrochloride, cysteamine hydrochloride and disodium ethylenediaminetetraacetic acid.

[0009] According to an exemplary embodiment of the present invention, the cationic surfactant is selected from one or more of dodecyltrimethylammonium bromide, tetradecyltrimethylammonium bromide and hexadecyltrimethylammonium bromide.

[0010] According to an embodiment of the present invention, the molar ratio of the cationic surfactant, the oxidant and the complex is 1:(1-10):(1-10), for example, 1:1:1, 1:5:5.

[0011] According to an embodiment of the present invention, the Ag-MOF material synthesis treatment agent further includes a solvent, and preferably the solvent is water.

[0012] According to an embodiment of the present invention, the pH of the Ag-MOF material synthesis treatment agent is 6.5 to 8, for example, 6.7, 6.8, 6.9, 7, 7.1, 7.2, 7.3, 7.4, or 7.5.

[0013] According to an exemplary embodiment of the present invention, in the Ag-MOF material synthesis treatment agent, the concentration of the cationic surfactant is 1 to 20 mM, the concentration of the oxidant is 1 to 100 mM, and the concentration of the complex is 1 to 100 mM.

[0014] According to an exemplary embodiment of the present invention, the Ag-MOF material synthesis treatment agent comprises raw materials: dodecyltrimethylammonium bromide, ammonium persulfate, cysteine ​​hydrochloride and water;

[0015] The molar ratio of the dodecyltrimethylammonium bromide, ammonium persulfate and cysteine ​​hydrochloride is 1:5:5;

[0016] The pH of the Ag-MOF material synthesis treatment agent is 6.5-7.5.

[0017] According to an exemplary embodiment of the present invention, the Ag-MOF material synthesis treatment agent comprises raw materials: tetradecyltrimethylammonium bromide, potassium persulfate, cysteamine hydrochloride and water;

[0018] The molar ratio of tetradecyltrimethylammonium bromide, potassium persulfate and cysteamine hydrochloride is 1:5:5;

[0019] The pH of the Ag-MOF material synthesis treatment agent is 6.5-7.5.

[0020] According to an exemplary embodiment of the present invention, the Ag-MOF material synthesis treatment agent comprises raw materials: tetradecyltrimethylammonium bromide, ammonium persulfate, cysteine ​​hydrochloride and water;

[0021] The molar ratio of tetradecyltrimethylammonium bromide, ammonium persulfate and cysteine ​​hydrochloride is 1:5:5;

[0022] The pH of the Ag-MOF material synthesis treatment agent is 6.5-7.5.

[0023] According to an exemplary embodiment of the present invention, the Ag-MOF material synthesis treatment agent comprises raw materials: hexadecyltrimethylammonium bromide, sodium persulfate, disodium ethylenediaminetetraacetic acid and water;

[0024] The molar ratio of hexadecyltrimethylammonium bromide, sodium persulfate and disodium ethylenediaminetetraacetic acid is 1:5:5;

[0025] The pH of the Ag-MOF material synthesis treatment agent is 6.5-7.5.

[0026] According to an exemplary embodiment of the present invention, the Ag-MOF material synthesis treatment agent comprises raw materials: hexadecyltrimethylammonium bromide, ammonium persulfate, cysteine ​​hydrochloride and water;

[0027] The molar ratio of hexadecyltrimethylammonium bromide, ammonium persulfate and cysteine ​​hydrochloride is 1:5:5;

[0028] The pH of the Ag-MOF material synthesis treatment agent is 6.5-7.5.

[0029] The present invention also provides an Ag-MOF material, which is constructed by the above-mentioned Ag-MOF material synthesis treatment agent on the surface of a silver substrate. The Ag-MOF material has a regular crystal structure.

[0030] According to an embodiment of the present invention, the silver substrate is selected from silver sheets, silver mesh or silver foil.

[0031] According to some embodiments of the present invention, the Ag-MOF material has a rod-like crystal structure.

[0032] According to some embodiments of the present invention, the Ag-MOF material has a hollow tubular crystal structure.

[0033] According to some embodiments of the present invention, the Ag-MOF material has a three-dimensional structure, such as a three-dimensional bird's nest structure.

[0034] The present invention also provides a method for preparing the above-mentioned Ag-MOF material, comprising the following steps: immersing a silver substrate into the Ag-MOF material synthesis treatment agent to obtain the Ag-MOF material.

[0035] According to an embodiment of the present invention, the soaking time is not less than 2 hours, for example, 3 hours or 4 hours.

[0036] According to an embodiment of the present invention, the soaking temperature is room temperature, which refers to 15 to 40°C.

[0037] When the silver substrate is immersed in the above-mentioned Ag-MOF material synthesis treatment agent, the presence of cationic surfactants significantly accelerates the silver leaching rate, promotes the formation of regular and orderly Ag-MOF crystals, and even forms a special and interesting "bird's nest" structure. The promoting effect of cationic surfactants is attributed to their adsorption on the silver surface, which enhances the oxidizing effect of the oxidant, and the formation of mixed micelles with the oxidant is conducive to the complexation of the complex with silver ions. The prepared Ag-MOF material has excellent antibacterial activity. The three-dimensional "bird's nest" structure has a higher specific surface area. When bacterial water comes into contact with it, it provides more interaction sites and faster silver ion release, resulting in higher antibacterial efficiency.

[0038] The present invention also provides the use of the above-mentioned Ag-MOF material as an antibacterial material, preferably as an antibacterial material for water bodies.

[0039] Beneficial effects

[0040] The present invention provides a neutral treatment agent containing a cationic quaternary ammonium salt surfactant, an oxidant, and a complex. By simply immersing various silver substrates in this treatment solution, Ag-MOF materials with regular crystal structures can be rapidly and gently formed, even forming three-dimensional "bird's nest" structures with higher specific surface areas. Compared to silver substrates not treated with this treatment agent, the Ag-MOF materials exhibited highly effective antimicrobial activity and water disinfection capabilities. The Ag-MOF materials of the present invention exhibit on-demand silver ion release and long-lasting antimicrobial activity, can treat large amounts of water, and have significant practical application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1These are the appearance pictures of different solutions: Ⅰ. 10 mM cationic surfactant dodecyltrimethylammonium bromide; Ⅱ. 50 mM oxidant ammonium persulfate; Ⅲ. 50 mM complex cysteine ​​hydrochloride; Ⅳ. 50 mM oxidant ammonium persulfate + 50 mM complex cysteine ​​hydrochloride; Ⅴ. Example 1 Ag-MOF synthesis treatment agent.

[0042] Figure 2 The SEM morphology images of the silver flake surface after treatment with different solutions (the scale of I-III is 100 μm, and the scale of IV is 10 μm): I. 10 mM cationic surfactant dodecyltrimethylammonium bromide; II. 50 mM oxidant ammonium persulfate; III. 50 mM complex cysteine ​​hydrochloride; IV. 50 mM oxidant ammonium persulfate + 50 mM complex cysteine ​​hydrochloride; V. Example 1 Ag-MOF synthesis treatment agent.

[0043] Figure 3 The sterilization effect diagram of silver sheets treated with different solutions: Ⅰ. 10mM cationic surfactant dodecyltrimethylammonium bromide; Ⅱ. 50mM oxidant ammonium persulfate; Ⅲ. 50mM complex cysteine ​​hydrochloride; Ⅳ. 50mM oxidant ammonium persulfate + 50mM complex cysteine ​​hydrochloride; Ⅴ. Example 1 Ag-MOF synthesis treatment agent.

[0044] Figure 4 Statistical graph of the sterilization efficiency of silver sheets after treatment in various embodiments and comparative examples.

[0045] Figure 5 This is the SEM morphology of the Ag-MOF material in Example 2;

[0046] Figure 6 This is the SEM morphology of the Ag-MOF material in Example 3. DETAILED DESCRIPTION

[0047] The technical solutions of the present invention will be described in further detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanations of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are encompassed within the scope of protection that the present invention is intended to protect.

[0048] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0049] In the following examples and comparative examples, the sterilization efficiency was obtained by the following method:

[0050] The bactericidal efficiency was evaluated by the traditional plate counting method, that is, the bactericidal efficiency of the silver substrate against E. coli before and after treatment was evaluated by the reduction rate of colony forming units (CFU). The treated silver substrates were cut into 1.0 cm × 1.0 cm pieces and then immersed in 1.0 mL of E. coli aqueous suspension (OD 600 =0.2) and incubated at 37°C for 0.5 hours. Finally, 100 μL of the diluted E. coli aqueous suspension was plated onto LB agar plates. After incubation at 37°C for 16-18 hours, the number of colonies was recorded and the percentage reduction in CFU (i.e., the bactericidal efficiency) was calculated using the following formula.

[0051]

[0052] Where c0 is the number of colonies in the blank group, and c is the number of colonies in the experimental group.

[0053] The substrates used in the following examples and comparative examples are the same, that is, silver sheets.

[0054] Example 1

[0055] Prepare 10mM dodecyltrimethylammonium bromide aqueous solution (such as Figure 1 As shown in Figure 1), 50 mM ammonium persulfate aqueous solution (as shown in Figure 2 Figure 1 II) and 50 mM cysteine ​​hydrochloride aqueous solution (as Figure 1 At room temperature, the three aqueous solutions were mixed in a volume ratio of 1:1:1, and the pH was adjusted to 7 to obtain Ag-MOF synthesis treatment agent 1 (as shown in FIG. Figure 1 (as shown in V in the figure).

[0056] Take the silver substrate and immerse it in the above Ag-MOF synthesis treatment agent 1 for 4 hours at room temperature. The SEM morphology of the silver substrate surface is as follows: Figure 2 As shown in Figure Ⅴ, the surface of the silver substrate treated with Ag-MOF synthetic treatment agent 1 forms Ag-MOF materials with regular crystal structures, and these Ag-MOF materials even form a three-dimensional "bird's nest" structure.

[0057] The bactericidal effect of the treated silver substrate was tested by the plate counting method. It was found that the silver substrate treated with Ag-MOF synthetic treatment agent 1 had an excellent bactericidal effect, without any living colonies (such as Figure 3 The sterilization efficiency is 100%.

[0058] Example 2

[0059] 10 mM tetradecyltrimethylammonium bromide aqueous solution, 50 mM potassium persulfate solution and 50 mM cysteamine hydrochloride solution were prepared respectively, and the three aqueous solutions were mixed at a volume ratio of 1:1:1 at room temperature, and the pH was adjusted to 7 to obtain Ag-MOF synthetic treatment agent 2. According to the preparation method of the silver-based antibacterial material for water disinfection constructed by the above-mentioned Ag-MOF synthetic treatment agent, a treated silver substrate 2 was obtained, and an Ag-MOF material having a rod-like crystal structure ( Figure 5 ), sterilization efficiency 95%.

[0060] Example 3

[0061] 10 mM hexadecyltrimethylammonium bromide aqueous solution, 50 mM sodium persulfate solution and 50 mM ethylenediaminetetraacetic acid disodium salt solution were prepared respectively, and the three aqueous solutions were mixed at a volume ratio of 1:1:1 at room temperature, and the pH was adjusted to 7 to obtain an Ag-MOF synthetic treatment agent 3. According to the preparation method of the silver-based antibacterial material for water disinfection constructed by the above-mentioned Ag-MOF synthetic treatment agent, a treated silver substrate 3 was obtained, and an Ag-MOF material having a hollow tubular crystal structure ( Figure 6 ), sterilization efficiency 60%.

[0062] Example 4

[0063] A 10 mM aqueous solution of tetradecyltrimethylammonium bromide, a 50 mM ammonium persulfate solution, and a 50 mM cysteine ​​hydrochloride solution were prepared, respectively, and mixed at a volume ratio of 1:1:1 at room temperature. The pH was adjusted to 7 to obtain an Ag-MOF synthetic treatment agent 4. The preparation method for constructing a silver-based antibacterial material for water disinfection using the above-mentioned Ag-MOF synthetic treatment agent yielded a treated silver substrate 4. An Ag-MOF material having a rod-like crystal structure was formed on the surface of the silver substrate, exhibiting a bactericidal efficiency of 80%.

[0064] Example 5

[0065] A 10 mM aqueous solution of hexadecyltrimethylammonium bromide, a 50 mM ammonium persulfate solution, and a 50 mM cysteine ​​hydrochloride solution were prepared, mixed at a volume ratio of 1:1:1 at room temperature, and the pH was adjusted to 7 to obtain an Ag-MOF synthetic treatment agent 5. The preparation method for constructing a silver-based antibacterial material for water disinfection using the Ag-MOF synthetic treatment agent described above yielded a treated silver substrate 5. An Ag-MOF material having a rod-like crystal structure formed on the surface of the silver substrate exhibited a bactericidal efficiency of 70%.

[0066] Comparative Example 1

[0067] A 10 mM aqueous solution of dodecyltrimethylammonium bromide was prepared and the pH was adjusted to 7. The treated silver substrate was obtained according to the preparation method of the silver-based antibacterial material for water disinfection constructed by the above-mentioned Ag-MOF synthetic treatment agent. The surface of the silver substrate was unable to form Ag-MOF material (such as Figure 2 The bactericidal effect of the treated silver substrate was tested by plate counting method, and the bactericidal efficiency was 13%.

[0068] Comparative Example 2

[0069] A 50 mM aqueous solution of ammonium persulfate was prepared and the pH was adjusted to 7. The treated silver substrate was obtained according to the preparation method of the silver-based antibacterial material for water disinfection constructed by the above-mentioned Ag-MOF synthetic treatment agent. The surface of the silver substrate could not form Ag-MOF material (such as Figure 2 II). The bactericidal effect of the treated silver substrate was tested by plate counting method, and the bactericidal efficiency was 10%.

[0070] Comparative Example 3

[0071] A 50 mM cysteine ​​hydrochloride solution was prepared and the pH was adjusted to 7. The treated silver substrate was obtained according to the preparation method of the silver-based antibacterial material for water disinfection constructed by the above-mentioned Ag-MOF synthetic treatment agent. The Ag-MOF material (such as Figure 2 III). The bactericidal effect of the treated silver substrate was tested by plate counting method, and the bactericidal efficiency was 6%.

[0072] Comparative Example 4

[0073] Prepare 50mM ammonium persulfate and 50mM cysteine ​​hydrochloride aqueous solutions respectively, and mix the two aqueous solutions in a volume ratio of 1:1 at room temperature (the mixture is as follows Figure 1 IV in the figure), adjusting the pH to 7, and constructing a silver-based antibacterial material for water disinfection according to the above-mentioned Ag-MOF synthetic treatment agent to obtain a treated silver substrate, on which the Ag-MOF material (such as Figure 2 IV). The bactericidal effect of the treated silver substrate was tested by plate counting method, and the bactericidal efficiency was 15%.

[0074] The above test results show that the Ag-MOF material of the embodiment exhibits efficient antibacterial activity and water disinfection ability, can treat a large amount of water, and has important practical application prospects.

[0075] The above describes the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. An Ag-MOF material synthesis treatment agent, characterized in that, The Ag-MOF material synthesis treatment agent comprises raw materials: a cationic surfactant, an oxidant and a complex; The cationic surfactant is selected from quaternary ammonium salts, and the alkyl group in the quaternary ammonium salt is selected from an alkyl chain with a carbon number of not less than 8; The oxidant is persulfate; The complex is selected from one or more of cysteine ​​hydrochloride, cysteamine hydrochloride and disodium ethylenediaminetetraacetic acid; The molar ratio of the cationic surfactant, the oxidant and the complex is 1:(1-10):(1-10); The pH of the Ag-MOF material synthesis treatment agent is 6.5-8.

2. The Ag-MOF material synthesis treatment agent according to claim 1, characterized in that The alkyl group in the quaternary ammonium salt is selected from an alkyl chain with a carbon number of 8 to 20; And / or, the oxidant is selected from one or more of ammonium persulfate, potassium persulfate and sodium persulfate.

3. The Ag-MOF material synthesis treatment agent according to claim 1, characterized in that The cationic surfactant is selected from one or more of dodecyltrimethylammonium bromide, tetradecyltrimethylammonium bromide and hexadecyltrimethylammonium bromide.

4. The Ag-MOF material synthesis treatment agent according to any one of claims 1 to 3, characterized in that: The Ag-MOF material synthesis treatment agent further includes a solvent, and the solvent is water.

5. The Ag-MOF material synthesis treatment agent according to claim 1, characterized in that The concentration of the cationic surfactant is 1-20 mM, the concentration of the oxidant is 1-100 mM, and the concentration of the complex is 1-100 mM.

6. The Ag-MOF material synthesis treatment agent according to claim 1, characterized in that The Ag-MOF material synthesis treatment agent comprises raw materials: dodecyltrimethylammonium bromide, ammonium persulfate, cysteine ​​hydrochloride and water; The molar ratio of the dodecyltrimethylammonium bromide, ammonium persulfate and cysteine ​​hydrochloride is 1:5:5; The pH of the Ag-MOF material synthesis treatment agent is 6.5 to 7.5; or, The Ag-MOF material synthesis treatment agent comprises raw materials: tetradecyltrimethylammonium bromide, potassium persulfate, cysteamine hydrochloride and water; The molar ratio of tetradecyltrimethylammonium bromide, potassium persulfate and cysteamine hydrochloride is 1:5:5; The pH of the Ag-MOF material synthesis treatment agent is 6.5 to 7.5; or, The Ag-MOF material synthesis treatment agent comprises raw materials: tetradecyltrimethylammonium bromide, ammonium persulfate, cysteine ​​hydrochloride and water; The molar ratio of tetradecyltrimethylammonium bromide, ammonium persulfate and cysteine ​​hydrochloride is 1:5:5; The pH of the Ag-MOF material synthesis treatment agent is 6.5 to 7.5; or, The Ag-MOF material synthesis treatment agent comprises raw materials: hexadecyltrimethylammonium bromide, sodium persulfate, disodium ethylenediaminetetraacetic acid and water; The molar ratio of hexadecyltrimethylammonium bromide, sodium persulfate and disodium ethylenediaminetetraacetic acid is 1:5:5; The pH of the Ag-MOF material synthesis treatment agent is 6.5 to 7.5; or, The Ag-MOF material synthesis treatment agent comprises raw materials: hexadecyltrimethylammonium bromide, ammonium persulfate, cysteine ​​hydrochloride and water; The molar ratio of cetyltrimethylammonium bromide, ammonium persulfate and cysteine ​​hydrochloride is 1:5:5; The pH of the Ag-MOF material synthesis treatment agent is 6.5-7.

5.

7. An Ag-MOF material, characterized in that The Ag-MOF material synthesis treatment agent according to any one of claims 1 to 6 is constructed on the surface of a silver substrate, and the Ag-MOF material has a regular crystal structure.

8. The Ag-MOF material according to claim 7, characterized in that The silver substrate is selected from silver sheets, silver mesh or silver foil.

9. The Ag-MOF material according to claim 7, characterized in that The Ag-MOF material has a rod-like crystal structure, a hollow tubular crystal structure or a three-dimensional bird's nest structure.

10. The method for preparing the Ag-MOF material according to any one of claims 7 to 9, characterized in that: The preparation method comprises the following steps: immersing a silver substrate into the Ag-MOF material synthesis treatment agent to obtain the Ag-MOF material.

11. Use of the Ag-MOF material according to any one of claims 7 to 9 as an antibacterial material.

12. The use according to claim 11, wherein: The Ag-MOF material is used as an antibacterial material for water.

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