Photothermal and photodynamic synergistic antibacterial hydrogel as well as preparation method and application thereof
By combining MoS2 nanosheets and dopamine in the hydrogel, photothermal photodynamic synergy is achieved, and the problem of single antibiotic resistance and nanomaterial response functions in the prior art is solved, which significantly improves the antibacterial effect and wound healing rate. Reduces toxic side effects.
Patent Information
- Application Number
- CN202411378604.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2024-12-27
AI Technical Summary
The prior art present challenges in preventing wound infection and promoting wound healing, especially due to the formation of drug-resistant strains and biofilms caused by excessive use of antibiotics, resulting in chronic wound and inflammatory responses, and nanomaterials are single or insensitive to wound response functions. , may bring toxic side effects.
Using photothermal and photodynamic synergistic antibacterial hydrogel, the synergistic effect of photothermal therapy and photodynamic therapy is achieved by combining MoS2 nanosheets and dopamine in the hydrogel, and using its high absorption and biocompatibility, the synergistic effect of photothermal therapy and photodynamic therapy is enhanced. , and regulate drug release through silver nitrate and carboxymethyl chitosan to improve the efficacy.
With low cytotoxicity and high biocompatibility, the hydrogel significantly enhances the antibacterial effect, can effectively remove bacterial biofilms, promote wound healing, reduce drug resistance and acute toxic side effects, and improve the safety and effect of treatment .
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Figure CN119185641A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of biomedicine technology, and in particular to a photothermal-photodynamic synergistic antibacterial hydrogel and a preparation method and application thereof. Background Art
[0002] Bacterial infection is one of the most critical challenges in the wound healing process, as microorganisms may cause severe tissue damage, lead to severe inflammatory responses and delay wound repair. To prevent wound infection, antibiotics have been widely used in clinical practice. However, their overuse / misuse has led to the emergence of multidrug-resistant (MDR) strains, resulting in stubborn biofilms and chronic wounds. The formed biofilms can protect bacteria from external attacks and increase their resistance to antibiotics. Therefore, there is an urgent need to develop technologies to accelerate the healing of bacterially infected wounds.
[0003] Most nanomaterials have a single or insensitive response function to the multiple microbial environments of the wound surface at different stages of treatment. At the same time, inappropriate nanodrug delivery exposed to the wound will also reduce the treatment results and even bring toxic side effects. Incorporating some functional nanodrugs into hydrogels can not only supplement the therapeutic function of hydrogels, but also regulate the wound microenvironment and accelerate wound repair. In addition, hydrogel-based drug delivery can regulate the sustained release of drugs to reduce drug resistance and reduce acute toxic side effects, thereby improving the efficacy as a potential wound treatment strategy. Hydrogels are natural or synthetic polymer networks with high water absorption. Due to their three-dimensional porous structure, high water content and flexibility, hydrogels are attractive biomaterials in the fields of drug delivery, vaccines, tissue engineering and biosensors. Adhesive injectable hydrogels can bond defective tissues together, thereby promoting normal wound healing.
[0004] Among various inorganic nanomaterials, molybdenum-based nanomaterials have attracted much attention in antibacterial research due to their unique physicochemical properties. Among them, MoS2 is a typical transition metal dihalide compound that forms a stable interlayer structure through S-Mo-S covalent bonds. MoS2 nanosheets have a large specific surface area and high conductivity, which makes them more capable of charge transfer between bacterial membranes and MoS2. The antibacterial activity of MoS2 nanosheets can be attributed to oxidative stress, the generation of reactive oxygen species (ROS), and the binding of MoS2 to intracellular components, resulting in direct damage to cell walls and membranes. Summary of the invention
[0005] In order to solve the problems in the prior art, the present invention provides a photothermal and photodynamic synergistic antibacterial hydrogel and its preparation method and application. In the present invention, polydopamine (PDA) has good adhesion, excellent light absorption and good biocompatibility, and MoS2 nanosheets have high near-infrared absorption and enzyme-like catalytic activity, which can achieve synergistic antibacterial between photothermal therapy (PTT) and photodynamic therapy (PDT) and promote the healing of bacterial-infected wounds.
[0006] The technical solution adopted by the present invention is as follows:
[0007] The preparation method of the photothermal and photodynamic synergistic antibacterial hydrogel comprises the following steps:
[0008] 1) Synthesis of MoS2 nanosheets: MoS2 raw powder is dispersed in isopropanol solution. Ultrasonic dispersion is performed for 1 hour, the resulting solution is centrifuged to collect the precipitate and purified, and then dried in a vacuum drying oven to obtain MoS2 nanosheets.
[0009] 2) Preparation of PDA@MoS2: The MoS2 nanosheets obtained in step 1) were ultrasonically dispersed in a mixed solution containing ethanol and deionized water for 30 minutes. Dopamine and ammonia were then added and reacted at room temperature in the dark for 24 hours. The resulting solution was centrifuged to collect the precipitate and purified to obtain PDA@MoS2.
[0010] Preparation of PMS@gel hydrogel: PDA@MoS2, SNP and silver nitrate aqueous solution are added into the reaction container in sequence, and carboxymethyl chitosan (CMCS) aqueous solution is added dropwise under high-speed stirring. After stirring at 70°C for 10 minutes, the mixture is cooled to room temperature to obtain a photothermal and photodynamic synergistic antibacterial hydrogel.
[0011] Furthermore, in the step 1), the mass concentration of MoS2 and isopropanol is 10-20 g / L.
[0012] Furthermore, the ultrasonic dispersion for 1 hour in step 1) is: ultrasonic dispersion for 1 hour in a 70W water bath.
[0013] Furthermore, the centrifugal collection and purification of the precipitate in step 1) are as follows: centrifugation at a rotation speed of 10,000 rpm for 15 minutes, and the precipitate is collected and washed three times with ethanol and deionized water respectively.
[0014] Furthermore, in the step 2), the mass ratio of MoS2 nanosheets to dopamine is 1:2-2:3, and the reaction conditions are room temperature and protected from light.
[0015] Furthermore, the centrifugal collection and purification of the precipitate in step 2) are as follows: centrifugation at a rotation speed of 10,000 rpm for 15 minutes, and the precipitate is collected and washed three times with deionized water.
[0016] Furthermore, in the step 3), the mass ratio of PDA@MoS2, SNP, silver nitrate and carboxymethyl chitosan is 0.36-1.8:0.3-0.9:0.5-2:10-40.
[0017] The present invention also provides the use of the photothermal and photodynamic synergistic antibacterial hydrogel in treating bacterially infected wounds.
[0018] The present invention has the following beneficial effects:
[0019] Ag inside the photothermal and photodynamic synergistic antibacterial hydrogel provided by the present invention + It is easy to interact with the amino and hydroxyl groups on the carboxymethyl chitosan chain to form a hydrogel, giving the hydrogel excellent antibacterial properties and gelation ability. The NO produced by the sodium nitroprusside (SNP) of the present invention can not only enhance the penetration of the therapeutic agent into the biofilm, but also synergize with the reactive oxygen species (ROS) produced by the MoS2 nanosheets to effectively remove the bacterial biofilm. The MoS2 nanosheets of the present invention have a large surface area and can directly contact bacteria. Their sharp edges can pierce the cell membrane or cell wall, thereby causing membrane stress and ultimately leading to the leakage of bacterial contents. At the same time, the PDA and MoS2 nanosheets in the present invention synergistically enhance the photothermal effect to inhibit bacterial growth. The photothermal and photodynamic synergistic antibacterial hydrogel has the characteristics of low cytotoxicity, good biocompatibility, excellent antibacterial effect, etc., and can promote the healing of bacterially infected wounds. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 This is a diagram of the preparation process of hydrogel.
[0021] Figure 2 It is the Fourier infrared spectra of MoS2 nanosheets and PDA@MoS2 prepared in Example 1.
[0022] Figure 3 (A) is a scanning electron microscope image of the MoS2 nanosheets prepared in Example 1; Figure 3 (B) is a transmission electron microscopy image of the MoS2 nanosheets prepared in Example 1.
[0023] Figure 4 This is a transmission electron microscope image of PDA@MoS2 prepared in Example 1.
[0024] Figure 5 It is a digital photo of the hydrogels prepared in Example 1 and the comparative example.
[0025] Figure 6 This is a scanning electron microscope image of the PMS@Gel hydrogel prepared in Example 1.
[0026] Figure 7This is the swelling rate diagram of the PMS@Gel hydrogel prepared in Example 1.
[0027] Figure 8 This is a digital photograph of the injectability and self-healing properties of the PMS@Gel hydrogel prepared in Example 1.
[0028] Fig. 9 It is a graph of cell survival rates after co-incubation of MoS2 nanosheets, PDA@MoS2 and PMS@Gel hydrogels prepared in Example 1 and Gel hydrogel prepared in Example 5 with human umbilical vein endothelial cells (HUVEC).
[0029] Fig.10 The graph shows the antibacterial effects of the PMS@Gel hydrogel prepared in Example 1 and the Gel hydrogel prepared in Example 4 after contacting Staphylococcus aureus and Escherichia coli with or without 808 nm light irradiation.
[0030] Fig.11 The figure is a graph showing the wound healing rates of the PMS@Gel hydrogel prepared in Example 1 and the Gel hydrogel prepared in Example 4 for infected wounds of mice at different times with or without 808 nm light irradiation. Specific implementation methods
[0031] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0032] The professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Unless otherwise specified, the raw materials and reagents used in the present invention are all commercially available products.
[0033] Example 1
[0034] The preparation method of the photothermal and photodynamic synergistic antibacterial hydrogel comprises the following steps:
[0035] 1) Synthesis of MoS2 nanosheets: Disperse 1 g of MoS2 raw powder in 100 mL of isopropanol solution, ultrasonically treat in a 70 W water bath for 1 h, centrifuge the obtained dispersion at 10,000 rpm for 15 min, collect the precipitate, wash the obtained precipitate with ethanol and deionized water three times each, and dry it in a vacuum drying oven to obtain MoS2 nanosheets.
[0036] 2) Preparation of PDA@MoS2: 0.125 g of MoS2 nanosheets obtained in step 1) were ultrasonically dispersed in a mixed solution containing 20 mL of ethanol and 45 mL of deionized water for 30 min. Then 0.25 g of dopamine and 1 mL of ammonia water were added, and the mixture was reacted at room temperature in the dark for 24 h. The obtained mixed solution was centrifuged at 10,000 rpm for 15 min, and the precipitate was collected and washed with deionized water 3 times to obtain PDA@MoS2.
[0037] 3) Preparation of PMS@gel hydrogel: 0.9 mL of 10 mg / mL PDA@MoS2, 0.1 mL of 20 mg / mL SNP, and 0.15 mL of 0.2 mol / L silver nitrate aqueous solution were added to the reaction vessel in sequence, and 3.85 mL of 25 mg / mL carboxymethyl chitosan (CMCS) aqueous solution was added dropwise under high-speed stirring. After stirring at 70°C for 10 min, the mixture was cooled to room temperature to obtain a photothermal-photodynamic synergistic antibacterial hydrogel. The obtained composite hydrogel is designated as PMS@Gel-1.
[0038] Example 2
[0039] The preparation method of the photothermal and photodynamic synergistic antibacterial hydrogel comprises the following steps:
[0040] The PDA@MoS2 prepared in Example 1 was dissolved in deionized water to prepare 2 mg / mL. 2 mg / mL PDA@MoS2 0.9 mL, 10 mg / mL SNP 0.1 mL and 0.1 mol / L silver nitrate aqueous solution 0.15 mL were added to the reaction container in sequence, and 12.5 mg / mL carboxymethyl chitosan (CMCS) aqueous solution 3.85 mL was added dropwise under high-speed stirring, stirred at 70 ° C for 10 min and cooled to room temperature to obtain a photothermal and photodynamic synergistic antibacterial hydrogel. The obtained composite hydrogel is represented as PMS@Gel-2.
[0041] Example 3
[0042] The preparation method of the photothermal and photodynamic synergistic antibacterial hydrogel comprises the following steps:
[0043] The PDA@MoS2 prepared in Example 1 was dissolved in deionized water to prepare 5 mg / mL. 0.9 mL of 5 mg / mL PDA@MoS2, 0.1 mL of 30 mg / mL SNP, and 0.15 mL of 0.4 mol / L silver nitrate aqueous solution were added to the reaction vessel in sequence, and 3.85 mL of 50 mg / mL carboxymethyl chitosan (CMCS) aqueous solution was added dropwise under high-speed stirring. After stirring at 70°C for 10 minutes, the mixture was cooled to room temperature to obtain a photothermal and photodynamic synergistic antibacterial hydrogel. The obtained composite hydrogel is represented as PMS@Gel-3.
[0044] Example 4
[0045] Take 0.15 mL of 0.2 mol / L silver nitrate aqueous solution, add 0.9 mL of deionized water, add 3.85 mL of 25 mg / mL carboxymethyl chitosan (CMCS) aqueous solution dropwise under high-speed stirring, stir at 70°C for 10 minutes and then cool to room temperature to obtain a silver ion antibacterial hydrogel. The obtained hydrogel is represented by Gel.
[0046] The preparation process of hydrogel is shown in Figure 1 .
[0047] The embodiments were tested, and the test conditions all followed the relevant national standards.
[0048] The structural characteristics of the MoS2 nanosheets and PDA@MoS2 prepared in Example 1 were analyzed using FTIR Fourier transform infrared spectrometer. Figure 2 As shown in the infrared absorption spectrum of PDA@MoS2, it can be seen that the main characteristic peaks of MoS2 appear in the range of 3000-2800 cm -1 , indicating that PDA@MoS2 was successfully prepared.
[0049] The microstructures of the MoS2 nanosheets and PDA@MoS2 prepared in Example 1 were analyzed using a SEM field emission scanning electron microscope and a transmission electron microscope (TEM). Figure 3 As shown in Figure 2, the SEM image of MoS2 nanosheets shows an irregular flake shape. The TEM image of MoS2 nanosheets shows a clear crystal structure, which is basically consistent with the TEM image reported in the literature. After adding dopamine, Figure 4 As shown, the thickness of PDA@MoS2 is significantly increased compared with that of the original MoS2 nanosheets, and a clear boundary layer is observed.
[0050] By observing the appearance morphology of the hydrogels prepared in Example 1 and the comparative example, Figure 5 It can be found that the hydrogel prepared in Example 1 has better gelling properties, no fluidity, and uniform gelling, while the hydrogel prepared in the comparative example has disadvantages such as slight fluidity or difficult or uneven gelling.
[0051] The morphology of the PMS@Gel hydrogel prepared in Example 1 was observed using a field emission scanning electron microscope. Figure 6 As shown, the PMS@Gel hydrogel has a porous structure and MoS2 nanosheets are uniformly dispersed in the hydrogel.
[0052] The swelling rate of the hydrogel was measured by immersing it in phosphate buffered saline (PBS) at 37°C for different periods of time. Figure 7 As shown, after immersion for 24 h, the swelling ratio of PMS@Gel increased by 1.8–2.0 times while maintaining morphological stability, which means that the hydrogel has good absorption of wound exudate.
[0053] The injectability and self-healing properties of the PMS@Gel hydrogel prepared in Example 1 were further studied. Figure 8 As shown, the PMS@Gel hydrogel can be smoothly squeezed out of the syringe and "CQMU" can be written on it. This injectability is conducive to its application to irregular wounds. In addition, the PMS@Gel hydrogel can be sheared and reassembled to heal into a complete hydrogel, indicating that the hydrogel has self-healing properties.
[0054] The MTT method was used to determine the cell biocompatibility of the MoS2 nanosheets, PDA@MoS2 and PMS@Gel hydrogels prepared in Example 1 and the Gel prepared in Example 4. Human umbilical vein endothelial cells (HUVEC) were cultured and the HUVEC cells were seeded in a 96-well plate. After the cells attached to the well plate, equal amounts of hydrogel extracts from different groups and corresponding amounts of MoS2 nanosheets and PDA@MoS2 solutions were added. After culturing for 24 hours at 37°C and 5% CO2, the cells were washed twice with PBS. Afterwards, 180 μL of culture medium and 20 μL of MTT solution were added to each well. After culturing for 4 hours, the supernatant was discarded and 150 μL of DMSO was added to each well. Finally, the absorbance value (OD value) was detected at a wavelength of 450 nm using an enzyme reader, and the cell survival rate was calculated. The results are as follows. Fig. 9 As shown, the cell viability of all groups reached more than 80%, indicating that the hydrogels had good biocompatibility.
[0055] The plate diffusion method was used to evaluate the antibacterial rate of the samples obtained in the example against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Staphylococcus aureus and Escherichia coli bacterial liquids were diluted to a bacterial concentration of 10 6 CFU / mL, 500μL of bacterial solution and equal amounts of hydrogel extracts from different groups were placed in a 24-well plate and co-cultured at 37°C for 30 minutes. The bacterial suspensions diluted to different concentrations were spread on agar plates. After 12 to 15 hours of culture (temperature was 37°C), visible colonies were formed on the agar plates. The bacterial survival rate can be quantitatively estimated by counting colonies (bacterial survival rate = bacterial concentration of the experimental group / bacterial concentration of the blank group * 100%). The results are shown in Fig.10 As shown in the figure, the sterilization rates of the PMS@Gel group against Staphylococcus aureus and Escherichia coli were 90.37% and 99.23% respectively under light-free conditions, and the sterilization rates of both bacteria under 808nm light reached more than 99.5%, indicating that the PMS@Gel hydrogel has good antibacterial ability.
[0056] The effect of the hydrogel prepared in the present invention on wound healing was evaluated by using a mouse wound infection model. After fully anesthetized Balb / c mice (18-22 g, half male and half female), a full-thickness circular wound was made on the back using a skin perforator with a diameter of 10 mm. Escherichia coli (50 μL, 10 8 CFU / mL), different groups of hydrogels were applied to the wound for 14 days, the healing of the infected wound was observed, and the wound area was calculated. Fig.11 As shown, on the 3rd and 14th days, the wound area in the PMS@Gel group was significantly reduced compared with the PBS group, indicating that PMS@Gel hydrogel has a positive effect on promoting the healing of infected wounds.
[0057] From the above data, it can be seen that the Ag inside the photothermal and photodynamic synergistic antibacterial hydrogel provided by the present invention + It is easy to interact with the amino and hydroxyl groups on the carboxymethyl chitosan chain to form a hydrogel, giving the hydrogel excellent antibacterial properties and gelation ability. The NO produced by the sodium nitroprusside (SNP) of the present invention can not only enhance the penetration of the therapeutic agent into the biofilm, but also synergize with the reactive oxygen species (ROS) produced by the MoS2 nanosheets to effectively remove the bacterial biofilm. The MoS2 nanosheets of the present invention have a large surface area and can directly contact bacteria. Their sharp edges can pierce the cell membrane or cell wall, thereby causing membrane stress and ultimately leading to the leakage of bacterial contents. At the same time, the PDA and MoS2 nanosheets in the present invention synergistically enhance the photothermal effect to inhibit bacterial growth. The photothermal and photodynamic synergistic antibacterial hydrogel has the characteristics of low cytotoxicity, good biocompatibility, excellent antibacterial effect, etc., and can promote the healing of bacterially infected wounds.
[0058] The above description is only a preferred specific implementation of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A method for preparing a photothermal and photodynamic synergistic antibacterial hydrogel, characterized in that: The steps include: 1) Synthesis of MoS2 nanosheets: MoS2 raw powder is dispersed in isopropanol solution, ultrasonically dispersed for 1 hour, the resulting solution is centrifuged to collect the precipitate and purified, and then dried in a vacuum drying oven to obtain MoS2 nanosheets; 2) Preparation of PDA@MoS2: The MoS2 nanosheets obtained in step 1) were ultrasonically dispersed in a mixed solution containing ethanol and deionized water for 30 min, and then dopamine and ammonia were added. The mixture was reacted at room temperature in the dark for 24 h. The resulting solution was centrifuged to collect the precipitate and purified to obtain PDA@MoS2. 3) Preparation of PDA@MoS2@SNP@gel hydrogel: PDA@MoS2, SNP and silver nitrate aqueous solution were added into the reaction container in sequence, and carboxymethyl chitosan (CMCS) aqueous solution was added dropwise under high-speed stirring. After stirring at 70°C for 10 minutes, the mixture was cooled to room temperature to obtain a photothermal and photodynamic synergistic antibacterial hydrogel.
2. The method for preparing the photothermal-photodynamic synergistic antibacterial hydrogel according to claim 1, characterized in that: The mass concentration of MoS2 and isopropanol in the step 1) is 10-20 g / L.
3. The method for preparing the photothermal and photodynamic synergistic antibacterial hydrogel according to claim 1, characterized in that: The ultrasonic dispersion for 1 hour in the step 1) is: ultrasonic dispersion for 1 hour in a 70W water bath.
4. The method for preparing the photothermal and photodynamic synergistic antibacterial hydrogel according to claim 1, characterized in that: The centrifugal collection and purification of the precipitate in step 1) are as follows: centrifugation at a rotation speed of 10,000 rpm for 15 minutes, and the precipitate is collected and washed three times with ethanol and deionized water respectively.
5. The method for preparing the photothermal and photodynamic synergistic antibacterial hydrogel according to claim 1, characterized in that: In the step 2), the mass ratio of MoS2 nanosheets to dopamine is 1:2-2:3, and the reaction conditions are room temperature and protected from light.
6. The method for preparing the photothermal and photodynamic synergistic antibacterial hydrogel according to claim 1, characterized in that: The centrifugal collection and purification of the precipitate in step 2) are as follows: centrifugation at a rotation speed of 10,000 rpm for 15 minutes, and the precipitate is collected and washed three times with deionized water.
7. The method for preparing the photothermal and photodynamic synergistic antibacterial hydrogel according to claim 1, characterized in that: In the step 3), the mass ratio of PDA@MoS2, SNP, silver nitrate and carboxymethyl chitosan is 0.36-1.8:0.3-0.9:0.5-2:10-40.
8. Use of the photothermal-photodynamic synergistic antibacterial hydrogel according to any one of claims 1 to 6 in the preparation of antibacterial drugs.