An organosilicon composite ZnO quantum dot antibacterial material, its preparation method and application

Abstract

The present invention relates to the field of biomedical antibacterial applications and discloses an organosilicon composite ZnO quantum dot antibacterial material, its preparation method, and application. The method comprises: using anhydrous ethanol as a solvent, adding a zinc salt, an alkali source, and a modifier to react fully to obtain modified ZnO quantum dots; using isopropyl alcohol as a solvent, adding hydrogenated silicone oil, vinyl silicone oil, and a platinum catalyst and mixing them uniformly to obtain an organosilicon precursor solution; adding the modified ZnO quantum dots to the organosilicon precursor solution, homogenizing, and then heating and curing to obtain an organosilicon composite ZnO quantum dot antibacterial material. The present invention successfully prepares a composite material of highly dispersed modified ZnO quantum dots and an organosilicon matrix. The composite material has excellent antibacterial properties at a low ZnO quantum dot content and can maximize the original properties of the organosilicon matrix. This organosilicon composite ZnO quantum dot antibacterial material provides a new technical approach for the application of organosilicon materials in the antibacterial field.

Description

Technical Field

[0001] This invention relates to the field of biomedical antibacterial applications, specifically to an organosilicon composite ZnO quantum dot antibacterial material, its preparation method, and its application. Background Technology

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

[0003] Quantum dots (QDs), as a type of nanoscale semiconductor material, exhibit antibacterial activity in addition to their unique optical properties. Especially under ultraviolet or visible light irradiation, they can kill bacteria through mechanisms such as generating reactive oxygen species (ROS), demonstrating potential antibacterial application value. However, exposed quantum dots are prone to aggregation in biological environments, exhibiting poor stability and potential biotoxicity, limiting their direct application. Organosilicones, on the other hand, are often used as carriers or matrices for antibacterial materials due to their excellent biocompatibility, chemical inertness, good film-forming properties, and flexibility. Chinese patent "CN109912982B" discloses a composite antibacterial material combining quantum dots and organosilicon, which not only improves the stability and dispersibility of quantum dots but also combines the antibacterial activity of quantum dots with the good biocompatibility of organosilicon, forming a novel composite material with synergistic antibacterial effects. Therefore, the development of quantum dot antibacterial materials based on organosilicon encapsulation has significant research value in fields such as biomedicine and environmental remediation.

[0004] Compared to traditional antibiotics, the advantage of using metal oxide nanoparticles (NPs) with antibacterial activity is a better balance between therapeutic efficacy and side effects. Furthermore, NPs can effectively kill pathogenic microorganisms without causing secondary pollution to the environment. Nano-zinc oxide (ZnO) has already demonstrated its immense potential as a photocatalyst in the market. It possesses good biocompatibility, stability, and bactericidal properties, and is inexpensive, easy to prepare, and non-toxic, showing promising application prospects in agriculture, medicine, and the environment. While current organosilicon composite zinc oxide quantum dot (ZnO QDs) antibacterial materials possess advantages such as high biocompatibility, strong photocatalytic activity, and good antibacterial properties, the following key drawbacks still exist in practical applications: 1. Interface compatibility issues: Due to the difference in surface energy, the organosilicon matrix and ZnO quantum dots are prone to phase separation, leading to quantum dot aggregation (antibacterial efficiency decreases by 4-5 orders of magnitude when the particle size exceeds 10 nm). Aggregation reduces the specific surface area, weakening the separation efficiency of photogenerated electron-hole pairs, resulting in a decrease in antibacterial efficiency instead of an increase. For example, traditional coupling treatment with γ-methacryloxypropyltrimethoxysilane (KH570) can only achieve the dispersion of ZnO particles with a diameter of 46 nm, which cannot meet the requirement of uniform coating of quantum dots. 2. There is a contradiction between mechanical properties and antibacterial properties. Antibacterial properties increase with the increase of ZnO quantum dots, but the increase of ZnO quantum dot content will hinder the movement of organosilicon polymer chain segments, resulting in a significant decrease in the elongation at break of organosilicon composite materials, which restricts their application in the medical field. Summary of the Invention

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

[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, zinc salt, alkali source and modifier are added and reacted fully at 60~100 °C to obtain modified ZnO quantum dots. The modifier includes at least one of straight-chain saturated fatty acids with 3-6 carbon atoms.

[0008] (2) Using isopropanol as a solvent, add hydrogen-containing silicone oil, vinyl silicone oil and platinum catalyst and mix evenly to obtain organosilicon precursor solution;

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

[0010] As a further preferred embodiment 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 alkali source includes at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, and ammonia water.

[0012] As a further preferred embodiment 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 embodiment of the present invention, the modifier further includes γ-glycidoxypropyltrimethoxysilane.

[0014] As a further preferred embodiment of the present invention, the hydrogen-containing silicone oil has a molecular weight of 5000-100000 Daltons and a hydrogen content greater than or equal to 1.5 wt%, and more preferably, the hydrogen content ranges from 1.5 to 2 wt%.

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

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

[0017] As a further preferred embodiment 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]. -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 modified ZnO quantum dots in the organosilicon composite ZnO quantum dot antibacterial material have a mass ratio of 0.1-1%, such as 0.1%, 0.3%, 0.5%, 0.6%, 0.8%, 1%, etc., which are non-limiting mass ratio values.

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

[0021] (1) Add zinc salt to anhydrous ethanol, heat and stir until the zinc salt is completely dissolved to obtain solution A;

[0022] (2) Add the alkali source to anhydrous ethanol, heat and stir to completely dissolve the alkali source, and obtain solution B;

[0023] (3) Mix solution A and solution B and add a modifier. React at 60~100 °C to obtain modified ZnO quantum dots.

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

[0025] According to another aspect of the present invention, the present invention also provides an application of organosilicon composite ZnO quantum dot antibacterial material as an antibacterial material, such as in the manufacture of 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 even with low ZnO quantum dot content, and can retain the original properties of the organosilicon matrix to the greatest extent. The modified ZnO quantum dots (4-6 nm) of this invention have ultra-high specific surface area and quantum confinement effect, and the number of active sites is several times higher than that of ordinary nano-ZnO for the same mass. The highly dispersed modified ZnO quantum dot and organosilicon composite antibacterial material of this invention provides a new technical approach for the application of organosilicon materials in the field of antibacterial applications. Attached Figure Description

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

[0028] Figure 1 XRD patterns of highly dispersed modified ZnO quantum dots prepared in Example 1 of this invention and commercially available nano-ZnO;

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

[0030] Figure 3 The UV-Vis diffuse reflectance spectra of highly dispersed modified ZnO quantum dots prepared in Example 1 of this invention and commercially available nano ZnO are shown.

[0031] Figure 4The water content and particle size distribution spectra of the highly dispersed modified ZnO quantum dots prepared in Example 1 of this invention and commercially available nano-ZnO are shown.

[0032] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0033] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

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

[0035] The hydrogen-containing silicone oils used below have a molecular weight of 10,000 Daltons and a hydrogen content of 1.5 wt%; the vinyl silicone oils have a molecular weight of 3,000 Daltons and a vinyl content of 0.4 wt%.

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

[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. Stir continuously 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. Stir continuously and heat under reflux at 70 °C for 1 h to obtain solution B. Mix solution B and solution A thoroughly and add 0.3 g of butyric acid (C4). Continue heating the reaction at 80 °C for 4 h to obtain highly dispersed modified ZnO quantum dots.

[0039] (2) Dissolve chloroplatinic acid in isopropanol solution to prepare 5 ppm chloroplatinic acid isopropanol solution (solution C). Then mix hydrogen-containing silicone oil and vinyl silicone oil at a molar ratio of 1:1 for hydrogen content and vinyl content and add them to isopropanol solution to obtain solution D. Add solution C dropwise to solution D to obtain solution E.

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

[0041] The highly dispersed 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 obtained in step (1) was analyzed by XRD using a Rigaku Ultima III X-ray diffractometer. For example... Figure 1 The XRD pattern of the sample is shown, indicating that it is a nano-zinc oxide material. The morphology and size of the highly dispersed modified ZnO quantum dot sample were analyzed using a Hitachi hT7700 transmission electron microscope (TEM). Figure 2 As shown, the highly dispersed modified ZnO quantum dots have a spherical morphology with a particle size of 5 ± 1 nm. Relatively speaking, smaller ZnO quantum dots have a larger specific surface area, and the H2O and O2 adsorbed on their surface are more easily converted into hydroxyl radicals (•OH) and superoxide radicals (•O2) by photogenerated holes and electrons. - Meanwhile, zinc ions (ZnO) from small-sized ZnO quantum dots 2+ The faster dissolution rate is beneficial for causing 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 PerkinElmer Lambda 950 UV / Vis / NIR spectrophotometer, such as... Figure 3 As shown, the results indicate that the highly dispersed modified ZnO quantum dot samples exhibit good visible light absorption in the wavelength range of 200-800 nm, which is due to the high crystallinity and nanoscale effect of the highly dispersed modified ZnO quantum dots.

[0044] (3) Water content and particle size were analyzed in highly dispersed modified ZnO quantum dot samples using a nanoparticle size and zeta potential analyzer from Malvern, UK. Figure 4 As shown, the results indicate that the highly dispersed modified ZnO quantum dot sample has a water content and a particle size of 5 ± 1 nm.

[0045] (4) The surface morphology of the organosilicon composite ZnO quantum dot antibacterial material sample was analyzed using a Hitach SU8220 field emission scanning electron microscope. The results showed that the surface morphology of the organosilicon composite ZnO quantum dot antibacterial material sample was good and without defects.

[0046] (5) Zn element analysis of the organosilicon composite ZnO quantum dot antibacterial material sample was performed using a Hitach SU8220 field emission scanning electron microscope from Japan. The results showed that the Zn element was very uniformly dispersed, proving that the ZnO quantum dots were fully dispersed in the organosilicon matrix, which helps to improve the antibacterial performance.

[0047] Comparative Example 1

[0048] As a control experiment of Example 1, organosilicon composite ZnO quantum dot antibacterial materials were prepared using the same method as in Example 1, except that step (1) butyric acid (C4) was omitted, the ZnO quantum dots were not modified, and the rest of the operations were consistent with those of Example 1.

[0049] Example 2

[0050] Organosilicon composite ZnO quantum dot antibacterial materials were prepared using a method that was basically the same as in Example 1, except that in step (1), 0.3 g butyric acid was replaced with 0.3 g propionic acid (C3), and the rest of the operation was the same as in Example 1.

[0051] Example 3

[0052] Organosilicon composite ZnO quantum dot antibacterial materials were prepared using a method that was basically the same as in Example 1, except that in step (1), 0.3 g butyric acid was replaced with 0.3 g hexanoic acid (C6), and the rest of the operation was the same as in Example 1.

[0053] Comparative Example 2

[0054] Organosilicon composite ZnO quantum dot antibacterial materials were prepared using a method that was basically the same as in Example 1, except that in step (1), 0.3 g butyric acid was replaced with 0.3 g lauric acid (C12), and the rest of the operation was the same as in Example 1.

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

[0056] Organosilicon composite ZnO quantum dot antibacterial materials were prepared using the same method as in Example 1, except that the ZnO quantum content of the antibacterial material was adjusted to 0.1 wt% in step (3), and the rest of the operation was the same as in Example 1.

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

[0058] Organosilicon composite ZnO quantum dot antibacterial materials were prepared using the same method as in Example 4, except that in step (1), 0.3 g of butyric acid was replaced with 0.3 g of a mixture of butyric acid and γ-glycidoxypropyltrimethoxysilane in a molar ratio of 1:1. The rest of the operation was the same as in Example 2.

[0059] Antibacterial performance test:

[0060] According to GB / T 31402-2015 Test Method for Antibacterial Properties of Plastic Surfaces, the antibacterial properties of the organosilicon composite ZnO quantum dot antibacterial materials provided in Examples 1-5 and Comparative Examples 1-2 were tested respectively. Pure organosilicon material was used as a blank control (i.e., directly cured from solution E in step (2) of Example 1). The specific test results are shown in Table 1.

[0061] Table 1

[0062]

[0063] This invention modifies the surface of ZnO quantum dots to introduce functional groups that can chemically or physically interact with the organosilicon network structure. The surface-modified ZnO quantum dots are dispersed in an organosilicon precursor, and an organosilicon network structure is formed through solution polymerization. The surface-modified ZnO quantum dots are then encapsulated within this network structure, resulting in an organosilicon composite ZnO quantum dot antibacterial material with excellent antibacterial effects. A comparison of the antibacterial performance of Example 1, Comparative Example 1, and the blank control group shows that, compared to unmodified ZnO quantum dots, the modified ZnO quantum dots, due to the presence of functional groups that can chemically or physically interact with the organosilicon network structure, significantly improve the antibacterial performance of the prepared antibacterial material. Compared to Comparative Example 3, the modifier used in Comparative Example 2, medium-chain lauric acid with a longer carbon chain, has greater molecular steric hindrance, resulting in weaker dispersibility of the modified ZnO quantum dots compared to butyric acid-modified ZnO quantum dots. Furthermore, lauric acid forms a dense carbon chain barrier on the surface of the ZnO quantum dots, extending the ZnO chain length. 2+ The dissolution pathway of lauric acid, and the fact that lauric acid can form a three-dimensional network through molecular entanglement in the organosilicon matrix, further blocking the active sites of ZnO, thus enabling the release of ZnO in Comparative Example 2. 2+ The slower reaction rate compared to Example 1 resulted in a significantly worse antibacterial effect in Comparative Example 2. Example 4, based on Example 1, significantly reduced the ZnO quantum dot content, yet the resulting antibacterial material still maintained good antibacterial performance. Because the amount of inorganic ZnO quantum dots in the organosilicon was reduced, the performance of the organosilicon substrate was maintained, resulting in excellent antibacterial properties along with superior mechanical properties, air permeability, and light transmittance, thus effectively broadening its application areas. Compared to Example 4, Example 5 used butyric acid and γ-glycidoxypropyltrimethoxysilane as synergistic modifiers (ZnO quantum dots). The prepared antibacterial material exhibited an antibacterial effect comparable to Example 1 even with a low ZnO quantum dot content.

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

Claims

1. A method for preparing an organosilicon composite ZnO quantum dot antibacterial material, characterized in that, Includes the following steps: (1) Using anhydrous ethanol as a solvent, zinc salt, alkali source and modifier are added and reacted fully at 60~100 °C to obtain modified ZnO quantum dots. The modifier includes at least one of straight-chain saturated fatty acids with 3-6 carbon atoms. (2) Using isopropanol as a solvent, add hydrogen-containing silicone oil, vinyl silicone oil and platinum catalyst and mix evenly to obtain organosilicon precursor solution; (3) Add the modified ZnO quantum dots to the organosilicon precursor solution, homogenize and heat to solidify, and obtain an organosilicon composite ZnO quantum dot antibacterial material in which the modified ZnO quantum dots are uniformly dispersed and coated in the organosilicon network structure.

2. The preparation method of 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 alkali source includes at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, and ammonia water.

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

4. The preparation method of the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that, The modifier also includes γ-glycidoxypropyltrimethoxysilane.

5. The preparation method of the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that, The hydrogen-containing silicone oil has a molecular weight of 5,000-100,000 Daltons and a hydrogen content greater than or equal to 1.5 wt%. And / or, the vinyl silicone oil has a molecular weight of 3000-5000 Daltons and a vinyl content greater than or equal to 0.4 wt%; And / or, the platinum catalyst is selected from any one of caster catalyst, chloroplatinic acid, and platinum dioxide.

6. The preparation method of the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that, The molar ratio of the hydrogen-containing silicone oil, vinyl silicone oil, and platinum catalyst is (4-6):(4-6):[(2-15)×10⁻⁶]. -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 preparation method of the organosilicon composite ZnO quantum dot antibacterial material according to claim 1, characterized in that, The modified ZnO quantum dots in the organosilicon composite ZnO quantum dot antibacterial material account for 0.1-1% of the total mass.

8. The method for preparing the organosilicon composite ZnO quantum dot antibacterial material according to any one of claims 1-7, characterized in that, Step (1) specifically includes: (1) Add zinc salt to anhydrous ethanol, heat and stir until the zinc salt is completely dissolved to obtain solution A; (2) Add the alkali source to anhydrous ethanol, heat and stir to completely dissolve the alkali source, and obtain solution B; (3) Mix solution A and solution B and add a modifier. React at 60~100 °C to obtain modified ZnO quantum dots.

9. An organosilicon composite ZnO quantum dot antibacterial material, characterized in that, It is prepared by the preparation method according to any one of claims 1-8.

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

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