A type of highly hydrophobic, visible light-responsive antibacterial gauze

Abstract

This invention discloses a highly hydrophobic, visible light-responsive bactericidal gauze, which is prepared through the following steps: 1) Mixing alkenyl-terminated polydimethylsiloxane and an organic solvent, then adding carbon nitride powder, heating in a water bath at 40℃-50℃ and stirring for 16-24 hours, followed by full light irradiation and stirring for 16-24 hours to obtain a mixture; 2) Centrifuging the mixture obtained in step 1) to remove unloaded alkenyl-terminated polydimethylsiloxane, dispersing the precipitate in ethanol and heating to dry, to obtain blocky carbon nitride loaded with alkenyl-terminated polydimethylsiloxane; 3) Mixing the blocky carbon nitride obtained in step 2) with the organic solvent and alkenyl-terminated polydimethylsiloxane evenly, then adding a platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane complex solution, immersing the gauze in the mixture, and heating and drying in a vacuum environment to obtain the final product. The gauze of this invention has the function of preventing blood adhesion and bacterial infection.

Description

Technical Field

[0001] This invention relates to a highly hydrophobic, visible light-responsive bactericidal gauze. Background Technology

[0002] Blood adhesion and bacterial infection are two major causes of wound infection. When blood comes into contact with a foreign surface, it forms a blood clot due to the hemostatic mechanisms that induce coagulation and platelet activation. However, this coagulation inevitably leads to strong adhesion of blood to the matrix, making it easy for blood to adhere to the matrix surface. Therefore, blood easily adheres to surfaces such as clothing and wound dressings, leading to wound infection and blood loss. Choon Hwai Yap et al. reported that modifying the surface of wound dressings to be hydrophobic can help control blood within the wound and partially solve the problem of blood adhesion. Furthermore, based on hydrodynamic effects, hydrophobic surfaces can effectively reduce the contact area between blood and the surface and reduce platelet adhesion. Therefore, developing a highly hydrophobic wound dressing is highly desirable.

[0003] Besides their role in blood clotting, bacteria are a major cause of wound infection. Bacteria first adhere to the wound surface, then multiply to form a biofilm that is difficult to remove, leading to persistent infection. Antibiotics are used to suppress bacterial infection. However, improper use of antibiotics can not only lead to antibiotic resistance but also increase drug-induced diseases. Therefore, preventing wound infection is also a problem that needs to be addressed.

[0004] Previous studies have shown that photocatalysts can kill bacteria by generating reactive oxygen species (ROS) that oxidize phospholipid films, proteins, and nucleic acids, and this effect is broad-spectrum. Carbon nitride, as a visible light catalyst, does not require high-voltage discharge light sources such as xenon or mercury lamps and can be used under normal lighting conditions. Therefore, obtaining dressings with hydrophobic bactericidal effects has become a new research topic. Summary of the Invention

[0005] To address the problems of existing gauze being prone to blood adhesion and lacking sterilization effect, this invention provides a highly hydrophobic, visible light-responsive sterilization gauze.

[0006] The strongly hydrophobic, visible light-responsive bactericidal gauze of the present invention is prepared through the following steps:

[0007] 1) After mixing alkenyl-terminated polydimethylsiloxane (PDMS) and an organic solvent, carbon nitride powder is added. The mixture is heated in a water bath at 40℃-50℃ and stirred for 16-24 hours, then irradiated with full light and stirred for 16-24 hours to obtain a mixed solution.

[0008] 2) centrifuging the mixture obtained in step 1) to remove the un-loaded alkenyl terminated polydimethylsiloxane, and dispersing the precipitate after centrifugation in ethanol and heating to dryness to obtain the block-like cubic carbon nitride loaded with alkenyl terminated polydimethylsiloxane;

[0009] 3) mixing the block-like cubic carbon nitride obtained in step 2) with an organic solvent, alkenyl terminated polydimethylsiloxane, adding platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex solution, immersing gauze in the mixture, and heating to dryness in a vacuum environment.

[0010] Mixing the cubic carbon nitride with alkenyl terminated polydimethylsiloxane in step 3) can connect the cubic carbon nitride particles to each other, increasing the adsorption stability on the gauze.

[0011] In step 1), the mass ratio of alkenyl terminated polydimethylsiloxane to cubic carbon nitride powder is 60:1-2, and the full light irradiation is performed using a 300w xenon lamp.

[0012] The organic solvent in step 1) and step 3) is the same, and is selected from any one of benzene, toluene, xylene, diethyl ether, tetrahydrofuran, and hexane.

[0013] The cubic carbon nitride powder in step 1) is obtained by heating dicyanamide to 550°C in static air for 4-4.5 hours, and then cooling to room temperature to obtain a block of cubic carbon nitride, which is then ground into powder.

[0014] In step 2), the centrifugation is performed at a speed of 10000-11000 r min -1 , the first centrifugation time is 20-30 minutes, and then subsequent centrifugation is performed, each time for 8-10 minutes; the heating temperature is 60-80°C, and the heating time is 12-16 hours.

[0015] In step 3), the mass ratio of block-like cubic carbon nitride to alkenyl terminated polydimethylsiloxane is 1:1.2-1.3; the mass percentage concentration of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex solution is 0.005 wt%, the mass ratio of block-like cubic carbon nitride to platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex is 262-265:1, the heating temperature is 60-80°C, and the heating time is 6-12 hours.

[0016] The alkenyl terminated polydimethylsiloxane in step 1) and step 3) is the same, and the alkenyl group is selected from any one of vinyl, propenyl, and butenyl.

[0017] Beneficial Effects: This invention addresses the problem of blood adhesion and bacterial infection that often occurs with existing gauze after bandaging by attaching carbon nitride loaded with alkenyl-terminated polydimethylsiloxane to gauze. This is achieved by making the gauze hydrophobic due to the alkenyl group and bactericidal due to the carbon nitride. Furthermore, compared to photocatalysts made from titanium dioxide that only utilize ultraviolet light (which accounts for less than 5% of the solar spectrum), the carbon nitride in this invention can utilize visible light for catalysis. Carbon nitride has higher energy efficiency and avoids the need for ultraviolet light photocatalysis, thus benefiting human health and expanding its application scenarios. Polydimethylsiloxane is a biocompatible material with wide applications in medicine. Carbon nitride is environmentally friendly, metal-free, and structurally stable, making it safer for use in wound dressings compared to other materials. Compared to other hydrogel-based wound dressings, the gauze-based wound dressing of this invention retains the breathability of gauze while preventing blood from adhering to it, thus preventing wound infection and accelerating wound healing. Attached Figure Description

[0018] Figure 1 Photograph of the bactericidal gauze with strong hydrophobicity and visible light responsiveness of the present invention;

[0019] Figure 2 The images show the hydrophobic effect of artificial blood being dripped onto ordinary gauze and the gauze of the present invention, respectively; wherein, a is a photo of the hydrophobic effect of ordinary gauze, b is a photo of the hydrophobic effect of the gauze of the present invention, and c is a photo of the hydrophobic effect of the gauze of the present invention after repeated rubbing.

[0020] Figure 3 The images show the bactericidal effect; where a is a photo of the bactericidal effect of hydrophobically modified titanium dioxide particles, b is a photo of the bactericidal effect of unmodified carbon nitride particles, and c is a photo of the bactericidal effect of hydrophobically modified carbon nitride. Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, but the present invention is not limited to the embodiments. Example

[0022] This invention relates to a highly hydrophobic, visible light-responsive bactericidal gauze, which is prepared through the following steps.

[0023] 1) Dicyandiamide was heated in a muffle furnace in static air at a heating rate of 2.3°C / min. −1 Heat to 550°C and hold for 4 hours, then cool at a rate of 1°C per minute. −1 After cooling to room temperature, large pieces of yellow carbon nitride were obtained. Then, the large pieces of carbon nitride were ground into carbon nitride powder using a grinding pestle and mortar.

[0024] 12g of vinyl-terminated polydimethylsiloxane (molecular weight approximately 62,000) and 4mL of toluene were mixed, and then 0.2g of the above-mentioned carbon nitride powder was added. The mixture was stirred with a magnetic stirrer for 24 hours under a water bath at 40°C, and then irradiated with a 300W xenon lamp for 16 hours to obtain a mixture.

[0025] 2) Centrifuge the mixture obtained in step 1) using a centrifuge (Xiangyi H1850), first at 10000 rmin. -1 Centrifuge at 10000 rpm for 20 minutes to remove unloaded vinyl-terminated polydimethylsiloxane, then add toluene at 10000 rpm. -1 Centrifugation for 10 minutes was repeated four times to thoroughly remove unloaded vinyl-terminated polydimethylsiloxane. Finally, the precipitate after centrifugation was dispersed in ethanol and dried in an oven at 60°C under normal pressure for 12 hours to obtain blocky carbon nitride loaded with vinyl-terminated polydimethylsiloxane.

[0026] 3) Mix 0.2g of the vinyl-terminated polydimethylsiloxane-loaded block carbon nitride obtained in step 2) with 2ml of toluene and 0.25g of vinyl-terminated polydimethylsiloxane. Then add 2μl of a platinum(O)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane complex solution with a mass percentage concentration of 0.005wt%. Immerse the prepared ordinary gauze in the mixture and dry it in a vacuum oven at 60°C for 6 hours to obtain a strongly hydrophobic, visible light-responsive sterilizing gauze (e.g., ...). Figure 1 (As shown). Example

[0027] The "toluene" in Example 1 was replaced with "tetrahydrofuran". Otherwise, it was the same as in Example 1, and a bactericidal gauze with strong hydrophobicity and visible light response was obtained. Example

[0028] By replacing "toluene" with "hexane" in Example 1, the process remains the same as in Example 1, resulting in a highly hydrophobic, visible light-responsive bactericidal gauze.

[0029] Strong hydrophobicity test

[0030] Artificial blood was dripped onto ordinary gauze, gauze from Example 1, and gauze from Example 1 that had been repeatedly rubbed. The results were as follows: Figure 2 a- Figure 2 As shown in c. A comparison reveals that ordinary gauze ( Figure 2 a) Due to its lack of hydrophobicity and large pores, blood easily adheres to this gauze; while the gauze of Example 1 ( Figure 2b) Due to its excellent hydrophobicity, blood can roll on this gauze without leaving a trace; even after repeated rubbing, the gauze ( Figure 2 c) It can also maintain its excellent hydrophobicity.

[0031] bactericidal test

[0032] Hydrophobically modified titanium dioxide particles (s-TiO2), unmodified carbon nitride particles (s-C3N4), and hydrophobically modified carbon nitride (so-C3N4) particles (i.e., the bulk carbon nitride loaded with vinyl-terminated polydimethylsiloxane in Example 1) were respectively mixed in 30 μl of 10 7 Staphylococcus aureus culture solution containing [number] cells / μl was irradiated under full light of a 300W xenon lamp for 2 hours, and then cultured in culture medium for 30 hours. The results are as follows: Figure 3 a- Figure 3 As shown in c. Comparison revealed that hydrophobically modified carbon nitride ( Figure 3 c) Compared to unmodified carbon nitride particles ( Figure 3 b), the number of colonies was significantly reduced; and carbon nitride ( Figure 3 b、 Figure 3 c) Compared to hydrophobically modified titanium dioxide ( Figure 3 (a) There were also significantly fewer colonies under full light, which indicates that hydrophobically modified carbon nitride has excellent bactericidal properties.

[0033] Unless otherwise specified, all technologies mentioned above refer to existing technologies.

[0034] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A strong hydrophobic, visible light responsive bactericidal gauze, characterized in that, Preparation by the following steps: 1) mixing alkenyl-terminated polydimethylsiloxane and organic solvent, then adding carbon nitride powder, heating in water bath at 40-50°C and stirring for 16-24 hours, then full light irradiation and stirring for 16-24 hours to obtain a mixture; 2) centrifuging the mixture obtained in step 1) to remove the unloaded alkenyl-terminated polydimethylsiloxane, dispersing the precipitate after centrifugation in ethanol and heating to dryness to obtain block carbon nitride loaded with alkenyl-terminated polydimethylsiloxane; 3) mixing the block carbon nitride obtained in step 2) with organic solvent, alkenyl-terminated polydimethylsiloxane, then adding platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex solution, immersing gauze in the mixture, and heating to dryness in vacuum environment to obtain; The carbon nitride powder in step 1) is obtained by heating dicyanamide in static air to 550°C for 4-4.5 hours, then cooling to room temperature to obtain block carbon nitride, and grinding the block carbon nitride into powder.

2. The strong hydrophobic, visible light responsive disinfectant gauze according to claim 1, characterized in that, In step 1), the mass ratio of alkenyl-terminated polydimethylsiloxane to carbon nitride powder is 60:1-2, and full light irradiation is performed using a 300w xenon lamp.

3. The strong hydrophobic, visible light responsive disinfectant gauze according to claim 1, characterized in that, The organic solvent in step 1) and step 3) is the same, selected from any one of benzene, toluene, xylene, diethyl ether, tetrahydrofuran, hexane.

4. The strong hydrophobic, visible light responsive disinfectant gauze according to claim 1, characterized in that, In step 2), centrifugation is carried out at a rotation speed of 10000-11000 r min -1 , the first centrifugation time being 20-30 minutes, and then subsequent centrifugations, each of which is 8-10 minutes; the heating temperature is 60-80℃, and the heating time is 12-16 hours.

5. The strongly hydrophobic, visible light responsive germicidal gauze according to claim 1, wherein, In step 3), the mass ratio of block carbon nitride to alkenyl-terminated polydimethylsiloxane is 1:1.2-1.3; the mass percentage concentration of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex solution is 0.005 wt%, the mass ratio of block carbon nitride to platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex is 262-265:1, the heating temperature is 60-80°C, and the heating time is 6-12 hours.

6. The strongly hydrophobic, visible light-responsive germicidal gauze according to any one of claims 1-5, wherein, The alkenyl-terminated polydimethylsiloxane in step 1) and step 3) is the same, and the alkenyl group is selected from any one of vinyl, propenyl, butenyl.

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