Organic silicon composite ZnO quantum dot antibacterial material as well as preparation method and application thereof

Abstract

The invention relates to the field of biomedical antibiosis, and discloses an organosilicon composite ZnO quantum dot antibacterial material and a preparation method and application thereof.The method comprises the steps that absolute ethyl alcohol serves as a solvent, zinc salt, an alkali source and a modifier are added for full reaction, and modified ZnO quantum dots are obtained; the preparation method comprises the following steps: by taking isopropanol as a solvent, adding hydrogen-containing silicone oil, vinyl silicone oil and a platinum catalyst, and uniformly mixing to obtain an organic silicon precursor solution; adding the modified ZnO quantum dots into the organic silicon precursor solution, homogenizing, heating and curing to obtain the organic silicon composite ZnO quantum dot antibacterial material. The high-dispersity composite material of the modified ZnO quantum dots and the organic silicon substrate is successfully prepared, the composite material has excellent antibacterial performance under the condition of low ZnO quantum dot content, and the original performance of the organic silicon substrate can be kept to the maximum extent; the organic silicon composite ZnO quantum dot antibacterial material provides a new technical approach for application of an organic silicon material in the antibacterial field.

Description

Technical Field

[0001] The present invention relates to the field of biomedical antibacterial materials, and in particular to an organosilicon composite ZnO quantum dot antibacterial material, a preparation method thereof, and applications thereof. Background Art

[0002] The use of antibiotics and antimicrobial resistance has increased exponentially due to the contamination of human life by pathogenic microorganisms, and the development of new antibiotics is currently slow. Cases of food contamination by various bacteria are gradually increasing. Therefore, addressing the increasing risk of pathogenic microbial contamination is a key focus of the current public health system, aiming to find new materials with antimicrobial properties to offset the slow development of new antibiotics. Compared to traditional sterilization technologies, metal oxide nanoparticles (NPs) have been proven to be a new line of defense against multidrug-resistant microorganisms in research over the past two decades.

[0003] Quantum dots (QDs), as nanoscale semiconductor materials, exhibit not only unique optical properties but also antimicrobial activity. In particular, under UV or visible light irradiation, they can kill bacteria through mechanisms such as the generation of reactive oxygen species (ROS), making them promising antimicrobial applications. However, exposed QDs are prone to aggregation in biological environments, exhibit poor stability, and may pose potential biotoxicity, limiting their direct application. Organosilicones, due to their excellent biocompatibility, chemical inertness, film-forming properties, and flexibility, are often used as carriers or matrices for antimicrobial materials. Chinese patent CN109912982B discloses a composite antimicrobial material combining quantum dots and organosilicones. This composite material not only improves the stability and dispersibility of the quantum dots but also combines the antimicrobial activity of the quantum dots with the excellent biocompatibility of organosilicones, resulting in a novel composite material with synergistic antimicrobial effects. Therefore, the development of organosilicon-encapsulated quantum dot antimicrobial materials holds significant research value in fields such as biomedicine and environmental purification.

[0004] Compared to traditional antibiotics, the use of antimicrobial metal oxide nanoparticles (NPs) offers the advantage of a better balance between therapeutic efficacy and side effects. Furthermore, metal oxide NPs can effectively kill pathogens without causing secondary environmental pollution. Nano-zinc oxide (ZnO) has demonstrated its promising potential as a photocatalyst in the market. Its excellent biocompatibility, stability, and bactericidal properties are coupled with its low cost, simple preparation, and non-toxicity, making it a promising material for applications in agriculture, medicine, and the environment. While current organosilicon-based zinc oxide quantum dots (ZnO QDs) antimicrobial materials offer advantages such as high biocompatibility, strong photocatalytic activity, and excellent antimicrobial properties, they still suffer from the following key drawbacks in practical applications: 1. Interfacial compatibility: Due to the surface energy difference, the organosilicon matrix and ZnO QDs are prone to phase separation, leading to QD agglomeration (antimicrobial efficacy decreases by 4-5 orders of magnitude when the particle size exceeds 10 nm). This agglomeration reduces the specific surface area, impairs the separation efficiency of photogenerated electron-hole pairs, and reduces antimicrobial efficacy rather than improving it. For example, conventional γ-methacryloxypropyltrimethoxysilane (KH570) coupling treatment can only achieve the dispersion of ZnO particles with a diameter of 46 nm, failing to meet the uniform coating requirements for quantum dots. 2. Mechanical properties conflict with antibacterial properties. While antibacterial properties improve with the addition of ZnO quantum dots, increasing the ZnO quantum dot content hinders the movement of silicone polymer chains, resulting in a significant decrease in the elongation at break of silicone composites, restricting their application in the medical field. Summary of the Invention

[0005] The purpose of the present invention is to explore a simple and easy method to synthesize antibacterial nano-ZnO materials and successfully compound them with organosilicon to realize their practical application in the antibacterial field.

[0006] To achieve the above objectives, the present invention provides a method for preparing an organosilicon composite ZnO quantum dot antibacterial material, comprising the following steps:

[0007] (1) using anhydrous ethanol as a solvent, adding a zinc salt, an alkali source and a modifier, and fully reacting at 60-100°C to obtain modified ZnO quantum dots, wherein the modifier includes at least one of a linear saturated fatty acid having 3-6 carbon atoms;

[0008] (2) Using isopropyl alcohol as solvent, hydrogenated silicone oil, vinyl silicone oil and platinum catalyst are added and mixed evenly to obtain an organosilicon precursor solution;

[0009] (3) The modified ZnO quantum dots are added to the organosilicon precursor solution, homogenized and then heated to solidify, and an organosilicon network structure is formed by polymerization of the organosilicon precursor solution. The uniformly dispersed modified ZnO quantum dots are coated in the network structure, and finally an organosilicon composite ZnO quantum dot antibacterial material is obtained in which the modified ZnO quantum dots are uniformly dispersed and coated in the organosilicon network structure.

[0010] As a further preferred technical solution of the present invention, the zinc salt includes at least one of zinc acetate dihydrate, zinc nitrate hexahydrate, zinc chloride, and zinc sulfate;

[0011] And / or, the alkaline source includes at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, and ammonia water.

[0012] As a further preferred technical solution of the present invention, the mass ratio of the zinc salt, the alkali source and the modifier is (1-1.5): (1-1.5): (0.01-0.1).

[0013] As a further preferred technical solution of the present invention, the modifier further includes γ-glycidyloxypropyltrimethoxysilane.

[0014] As a further preferred technical solution of the present invention, the molecular weight of the hydrogen-containing silicone oil is 5000-100000 Daltons, the hydrogen content is greater than or equal to 1.5 wt%, and the hydrogen content is further preferably in the range of 1.5-2 wt%.

[0015] And / or, the molecular weight of the vinyl silicone oil is 3000-5000 Daltons, the vinyl content is greater than or equal to 0.4wt%, and more preferably the vinyl content is 0.4-0.6wt%;

[0016] And / or, the platinum catalyst is selected from any one of Custer catalyst, chloroplatinic acid, and platinum dioxide.

[0017] As a further preferred technical solution of the present invention, the molar ratio of the hydrogen-containing silicone oil, vinyl silicone oil and platinum catalyst is (4-6): (4-6): [(2-15) × 10 -6 ];

[0018] And / or, the molar ratio of the hydrogen content of the hydrogen-containing silicone oil to the vinyl content of the vinyl silicone oil is 1:1.

[0019] As a further preferred technical solution of the present invention, the mass proportion of modified ZnO quantum dots in the organic silicon composite ZnO quantum dot antibacterial material is 0.1-1%, for example, 0.1%, 0.3%, 0.5%, 0.6%, 0.8%, 1% and other non-limiting mass proportion values.

[0020] As a further preferred technical solution of the present invention, step (1) specifically includes:

[0021] (1) adding zinc salt to anhydrous ethanol, heating and stirring to completely dissolve the zinc salt to obtain solution A;

[0022] (2) adding an alkali source to anhydrous ethanol, heating and stirring to completely dissolve the alkali source to obtain solution B;

[0023] (3) Solution A and solution B were mixed and a modifier was added, and the mixture was fully reacted at 60-100 °C to obtain modified ZnO quantum dots.

[0024] According to another aspect of the present invention, the present invention further provides an organosilicon composite ZnO quantum dot antibacterial material, which is prepared by the preparation method of the first aspect mentioned above.

[0025] According to another aspect of the present invention, the present invention also provides an application of an organosilicon composite ZnO quantum dot antibacterial material as an antibacterial material, such as for making antibacterial medical devices.

[0026] This invention successfully prepared a composite material of highly dispersed modified ZnO quantum dots and an organosilicon matrix. This composite material maintains excellent antibacterial properties at low ZnO quantum dot content, maximizing the original properties of the organosilicon matrix. The modified ZnO quantum dots (4-6 nm) exhibit ultra-high specific surface area and quantum confinement, with the number of active sites several times greater than that of conventional nano-ZnO at the same mass. This highly dispersed composite antibacterial material of modified ZnO quantum dots and organosilicon provides a new technological approach for the application of organosilicon materials in the antibacterial field. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Figure 1 XRD spectra of the highly dispersed modified ZnO quantum dots prepared in Example 1 of the present invention and commercially available nano ZnO;

[0029] Figure 2 Transmission electron microscopy images of highly dispersed modified ZnO quantum dots prepared in Example 1 of the present invention, with scales of (a) and (b) being 20 nm and 10 nm respectively;

[0030] Figure 3 UV-visible diffuse reflectance spectra of the highly dispersed modified ZnO quantum dots prepared in Example 1 of the present invention and commercially available nano-ZnO;

[0031] Figure 4The water and particle size spectra of the highly dispersible modified ZnO quantum dots prepared in Example 1 of the present invention and commercially available nano-ZnO.

[0032] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0033] The following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0034] Unless otherwise defined, the technical terms used in the following examples have the same meanings as commonly understood by those skilled in the art to which this invention belongs. The experimental reagents used in the following examples, unless otherwise specified, are conventional biochemical reagents; the experimental methods described, unless otherwise specified, are conventional methods.

[0035] The molecular weight of the hydrogenated silicone oil used below is 10,000 Daltons, and the hydrogen content is 1.5 wt %; the molecular weight of the vinylated silicone oil used below is 3,000 Daltons, and the vinyl content is 0.4 wt %.

[0036] Example 1: ZnO quantum content is 1wt%

[0037] This embodiment provides an organosilicon composite ZnO quantum dot antibacterial material, the preparation method of which is as follows:

[0038] (1) Take 5.5 g of zinc acetate dihydrate and add it to 100 mL of anhydrous ethanol solution, continue stirring and heat under reflux at 80°C for 2 h to obtain solution A. Take 5 g of sodium hydroxide and add it to 100 mL of anhydrous ethanol solution, continue stirring and heat under reflux at 70°C for 1 h to obtain solution B. Solution B and solution A are fully mixed, and 0.3 g of butyric acid (C4) is added. The reaction is continued under heating at 80°C for 4 h to obtain highly dispersed modified ZnO quantum dots.

[0039] (2) Dissolve chloroplatinic acid in isopropanol solution to prepare a 5 ppm chloroplatinic acid isopropanol solution (solution C). Then, hydrogenated silicone oil and vinyl silicone oil are mixed at a molar ratio of hydrogen content to vinyl content of 1:1 and added to the isopropanol solution to obtain solution D. Solution C is added dropwise to solution D to obtain solution E.

[0040] (3) The highly dispersed modified ZnO quantum dots were added to solution E, homogenized, heated to 80 °C and cured for 1 h to obtain an organosilicon composite ZnO quantum dot antibacterial material with a ZnO quantum content of 1 wt%.

[0041] The highly dispersible modified ZnO quantum dots and antibacterial material samples prepared in Example 1 were tested as follows:

[0042] (1) The highly dispersed modified ZnO quantum dot sample prepared in step (1) was subjected to XRD analysis using an Ultima III X-ray diffractometer from Rigaku Corporation, Japan. Figure 1 The XRD spectrum of the sample is shown in Figure 2, which shows that the sample is a nano zinc oxide material. The morphology and size of the prepared highly dispersed modified ZnO quantum dot sample were analyzed using a transmission electron microscope hT7700 from Hitachi, Japan. Figure 2 As shown in the figure, the morphology of the highly dispersed modified ZnO quantum dots is round and the particle size is 5±1 nm. Relatively speaking, the small-sized ZnO quantum dots have a larger specific surface area, and the H2O and O2 adsorbed on the surface are more easily converted into hydroxyl radicals (•OH) and superoxide radicals (•O2 - ), while the zinc ions of small-sized ZnO quantum dots (Zn 2+ ) The dissolution rate is relatively faster, which is beneficial to cause oxidative damage to bacterial DNA and proteins, thereby improving the antibacterial effect.

[0043] (2) The optical properties of the highly dispersed modified ZnO quantum dot samples were analyzed using a Lambda 950 UV / Vis / NIR spectrophotometer from PerkinElmer, USA. Figure 3 As shown in the figure, the results show that the highly dispersed modified ZnO quantum dots sample shows good visible light absorption in the wavelength range of 200-800 nm, which is due to the higher crystallinity and nanosize effect of the highly dispersed modified ZnO quantum dots.

[0044] (3) The water and particle size analysis of the highly dispersed modified ZnO quantum dot samples were performed using the nanoparticle size and Zeta potential analyzer of Malvern, UK. Figure 4 As shown, the results indicate that the modified ZnO quantum dots sample is highly dispersible in water and the particle size is 5 ± 1 nm.

[0045] (4) The surface morphology of the organosilicon composite ZnO quantum dot antibacterial material sample was analyzed using a SU8220 field emission scanning electron microscope produced by Hitach Company of Japan. The results showed that the surface morphology of the organosilicon composite ZnO quantum dot antibacterial material sample was good and had no defects.

[0046] (5) The Zn element was analyzed on the samples of organosilicon composite ZnO quantum dot antibacterial material using a SU8220 field emission scanning electron microscope produced by Hitach Company of Japan. The results showed that the Zn element was very evenly dispersed, proving that the ZnO quantum dots were fully dispersed in the organosilicon matrix, which helped to improve the antibacterial performance.

[0047] Comparative Example 1

[0048] As a control experiment of Example 1, an organosilicon composite ZnO quantum dot antibacterial material was prepared by a method substantially the same as that of Example 1, with the only difference being that step (1) butyric acid (C4) was omitted, the ZnO quantum dots were not modified, and the remaining operations remained the same as those of Example 1.

[0049] Example 2

[0050] The organosilicon composite ZnO quantum dot antibacterial material was prepared by a method basically the same as that in Example 1, the only difference was that 0.3 g of butyric acid was replaced by 0.3 g of propionic acid (C3) in step (1), and the rest of the operations were consistent with Example 1.

[0051] Example 3

[0052] The organosilicon composite ZnO quantum dot antibacterial material was prepared by a method basically the same as that in Example 1, the only difference was that 0.3 g of butyric acid was replaced by 0.3 g of hexanoic acid (C6) in step (1), and the rest of the operations were consistent with Example 1.

[0053] Comparative Example 2

[0054] The organosilicon composite ZnO quantum dot antibacterial material was prepared by a method basically the same as that in Example 1, the only difference was that 0.3 g of butyric acid was replaced by 0.3 g of lauric acid (C12) in step (1), and the rest of the operations were the same as those in Example 1.

[0055] Example 4: ZnO quantum content is 0.1wt%

[0056] The organosilicon composite ZnO quantum dot antibacterial material was prepared by a method basically the same as that in Example 1, with the only difference being that the ZnO quantum dot content of the antibacterial material was adjusted to 0.1 wt % in step (3), and the rest of the operations were the same as those in Example 1.

[0057] Example 5: ZnO quantum content is 0.1wt%

[0058] The organosilicon composite ZnO quantum dot antibacterial material was prepared by a method basically the same as that in Example 4, except that in step (1), 0.3 g of butyric acid was replaced by 0.3 g of a mixed modifier of butyric acid and γ-glycidyloxypropyltrimethoxysilane in a molar ratio of 1:1, and the rest of the operations were consistent with those in Example 2.

[0059] Antibacterial performance test:

[0060] According to the test method for antibacterial performance of plastic surfaces in accordance with GB / T 31402-2015, the antibacterial performance of the organosilicon composite ZnO quantum dot antibacterial materials provided in Examples 1-5 and Comparative Examples 1-2 was tested, respectively. Pure organosilicon material was used as a blank control (i.e., obtained by directly curing solution E in step (2) of Example 1). The specific test results are shown in Table 1.

[0061] Table 1

[0062]

[0063] The present invention modifies the surface of ZnO quantum dots, introduces functional groups that can interact chemically or physically with the organosilicon network structure, disperses the surface-modified ZnO quantum dots in an organosilicon precursor, forms an organosilicon network structure by solution polymerization, and encapsulates the surface-modified ZnO quantum dots in the network structure. The resulting organosilicon composite ZnO quantum dot antibacterial material has excellent antibacterial effect. Comparison of the antibacterial properties of Example 1 with Comparative Example 1 and the blank control group shows that compared with the unmodified ZnO quantum dots, the modified ZnO quantum dots have significantly improved antibacterial properties due to the functional groups that can interact chemically or physically with the organosilicon network structure. Compared with Comparative Example 3, the modifier in Comparative Example 2 uses medium-chain lauric acid with a longer carbon chain, which has a large molecular steric hindrance, making the dispersion of the modified ZnO quantum dots weaker than that of the butyric acid-modified ZnO quantum dots; in addition, lauric acid will form a dense carbon chain barrier on the surface of the ZnO quantum dots to extend the Zn 2+ The dissolution path of lauric acid in the silicone matrix can also form a three-dimensional network through molecular entanglement, further blocking the active sites of ZnO, so that the ZnO released in Comparative Example 2 2+ The speed is slower than that of Example 1, resulting in a significant deterioration in the antibacterial effect of Comparative Example 2. Example 4, based on Example 1, greatly reduces the content of ZnO quantum dots, and the resulting antibacterial material can still maintain a good antibacterial effect. Since the amount of inorganic particle ZnO quantum dots doped in the organosilicon is reduced, the performance of the organosilicon substrate is maintained, so that while having good antibacterial properties, it also has superior mechanical properties, air permeability, and light transmittance, thereby effectively broadening its application field. Compared with Example 4, Example 5 uses butyric acid and γ-glycidyloxypropyltrimethoxysilane as a synergistic modifier ZnO quantum dots. The antibacterial material prepared has an antibacterial effect comparable to that of Example 1 at a low content of ZnO quantum dots.

[0064] Although specific embodiments of the present invention are described above, those skilled in the art should understand that these are merely examples and that various changes or modifications may be made to the embodiments without departing from the principles and essence of the present invention. The scope of protection of the present invention is limited only by the appended claims.

Claims

1. A method for preparing an organosilicon composite ZnO quantum dot antibacterial material, characterized in that: The following steps are involved: (1) using anhydrous ethanol as a solvent, adding a zinc salt, an alkali source and a modifier, and fully reacting at 60-100°C to obtain modified ZnO quantum dots, wherein the modifier includes at least one of a linear saturated fatty acid having 3-6 carbon atoms; (2) Using isopropyl alcohol as solvent, hydrogenated silicone oil, vinyl silicone oil and platinum catalyst are added and mixed evenly to obtain an organosilicon precursor solution; (3) The modified ZnO quantum dots are added to the organosilicon precursor solution, homogenized and then heated to solidify, thereby obtaining an organosilicon composite ZnO quantum dot antibacterial material in which the modified ZnO quantum dots are uniformly dispersed and coated in an organosilicon network structure.

2. The method for preparing the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that: The zinc salt includes at least one of zinc acetate dihydrate, zinc nitrate hexahydrate, zinc chloride, and zinc sulfate; And / or, the alkaline source includes at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, and ammonia water.

3. The method for preparing the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that: The mass ratio of the zinc salt, the alkali source and the modifier is (1-1.5): (1-1.5): (0.01-0.1).

4. The method for preparing the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that: The modifier further includes γ-glycidoxypropyltrimethoxysilane.

5. The method for preparing the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that: The molecular weight of the hydrogen-containing silicone oil is 5000-100000 Daltons, and the hydrogen content is greater than or equal to 1.5wt%; and / or, the molecular weight of the vinyl silicone oil is 3000-5000 Daltons, and the vinyl content is greater than or equal to 0.4wt%; And / or, the platinum catalyst is selected from any one of Custer catalyst, chloroplatinic acid, and platinum dioxide.

6. The method for preparing the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that: The molar ratio of the hydrogenated silicone oil, vinyl silicone oil and platinum catalyst is (4-6): (4-6): [(2-15) × 10 -6 ]; And / or, the molar ratio of the hydrogen content of the hydrogen-containing silicone oil to the vinyl content of the vinyl silicone oil is 1:

1.

7. The method for preparing the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that: The mass proportion of the modified ZnO quantum dots in the organosilicon composite ZnO quantum dot antibacterial material is 0.1-1%.

8. The method for preparing the organosilicon composite ZnO quantum dot antibacterial material according to any one of claims 1 to 7, characterized in that: Step (1) specifically includes: (1) adding zinc salt to anhydrous ethanol, heating and stirring to completely dissolve the zinc salt to obtain solution A; (2) adding an alkali source to anhydrous ethanol, heating and stirring to completely dissolve the alkali source to obtain solution B; (3) Solution A and solution B were mixed and a modifier was added, and the mixture was fully reacted at 60-100 °C to obtain modified ZnO quantum dots.

9. An organosilicon composite ZnO quantum dot antibacterial material, characterized in that: The method is prepared according to any one of claims 1 to 8.

10. Use of the organosilicon composite ZnO quantum dot antibacterial material according to claim 9 as an antibacterial material.

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