A preparation method and application of a carbon quantum dot gel material based on a front-end aggregation means and a composite film thereof

Abstract

The application belongs to the field of nanomaterial preparation and processing, and mainly relates to a preparation method and application of carbon quantum dot gel material based on front-end polymerization means. Acrylamide, 1-vinyl-2-pyrrolidone and hydroxypropyl acrylate are used as hydrogel monomers, the hydrogel monomers, carbon quantum dot monomers citric acid and polyethyleneimine and an oxidant ammonium persulfate are dissolved in a solvent, and then a reducing agent N, N, N', N'-tetramethyl ethylenediamine is added and uniformly mixed to obtain a front-end polymerization solution; the surface of the front-end polymerization solution is heated and induced to obtain the carbon quantum dot gel material based on the front-end polymerization means; and then a microfluidic electrospinning technology is used to form a carbon quantum dot gel material composite film which can be used for wound dressings in cooperation with a degradable biopolymer material, so that the problems of small specific surface area and low porosity of the hydrogel material directly used as a wound dressing are further solved, and the effect of the wound healing application is optimized.

Description

Technical Field

[0001] This invention belongs to the field of nanomaterial preparation and processing, and mainly relates to a method for preparing carbon quantum dot gel materials and their composite films based on front-end polymerization and their applications. Background Technology

[0002] Carbon quantum dots, as an emerging carbon-based nanomaterial, have attracted much attention in the biomedical field due to their unique physicochemical properties and have been widely used in bioimaging, biomedicine, and other fields, including wound care materials. Currently, the main methods for preparing carbon quantum dots and their composites include hydrothermal / solvothermal methods, microwave-assisted methods, laser ablation methods, and chemical oxidation methods. However, these methods typically require sophisticated synthesis equipment and have low synthesis efficiency. Therefore, how to rapidly and efficiently prepare carbon quantum dots while maintaining the functionality of the material is a key factor restricting its development. For example, the existing technology CN106364124A discloses a method for preparing an antibacterial and formaldehyde-removing composite fiber membrane. While this process uses hot pressing and adhesives to solve the compatibility problem, the preparation method is cumbersome and complex, and the prepared material has poor antibacterial properties, affecting practical use. Summary of the Invention

[0003] To address the shortcomings of the existing technologies, the present invention aims to provide a method for preparing carbon quantum dot gel materials and their composite films based on front-end polymerization, and their applications. The invention utilizes a front-end polymerization reaction mode to rapidly and conveniently synthesize in-situ doped carbon quantum dot gels with excellent compatibility, making it possible to achieve "on-the-spot" medical materials.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A method for preparing carbon quantum dot gel materials based on front-end polymerization includes the following steps: Using acrylamide, 1-vinyl-2-pyrrolidone, and hydroxypropyl acrylate as hydrogel monomers, a mixed solution was obtained by dissolving the hydrogel monomers, carbon quantum dot monomers citric acid and polyethyleneimine, and the oxidant ammonium persulfate in a solvent.

[0005] The reducing agent N,N,N′,N′-tetramethylethylenediamine was added to the mixed solution and stirred rapidly to obtain the front-end polymerization solution. The oxidant was ammonium persulfate and the reducing agent was N,N,N′,N′-tetramethylethylenediamine. The addition of the redox components made the reaction occur rapidly and released a large amount of heat to provide power for the thermal initiation process, so as to ensure that the crosslinking occurs in the form of the front end.

[0006] The surface of the front-end polymerization solution is heated and induced to undergo a redox reaction and release heat, which causes a reverse front-end polymerization reaction between the hydrogel monomers, resulting in a carbon quantum dot gel material based on the front-end polymerization method.

[0007] In a preferred embodiment of the present invention, the oxidant is selected from one of persulfate (ammonium persulfate), hydrogen peroxide, and organic peroxide, with ammonium persulfate being the most preferred oxidant.

[0008] In a preferred embodiment of the present invention, the solvent is N,N-dimethylformamide; in the mixed solution, the mass fractions of acrylamide are 10 to 20 parts, the mass fractions of 1-vinyl-2-pyrrolidone are 30 to 90 parts, the mass fractions of hydroxypropyl acrylate are 10 to 20 parts, the mass fractions of N,N-dimethylformamide are 30 to 90 parts, the mass fractions of ammonium persulfate are 0.05 to 0.8 parts, the mass fractions of citric acid are 1 to 20 parts, and the mass fractions of polyethyleneimine are 1 to 20 parts; in the prepolymerization solution, the mass fractions of N,N,N',N'-tetramethylethylenediamine are 0.05 to 0.8 parts.

[0009] In a preferred embodiment of the present invention, the mixed solution needs to be dissolved and mixed until it is clear and transparent; the purity of citric acid and polyethyleneimine is 98% or higher, and the purity of acrylamide, 1-vinyl-2-pyrrolidone, hydroxypropyl acrylate, N,N-dimethylformamide, ammonium persulfate, and N,N,N′,N′-tetramethylethylenediamine reagents is 98% or higher.

[0010] In a preferred embodiment of the present invention, the heating-induced condition is to remove the heat source when the stable front can be observed using an infrared thermal imager, and the heating time is 15s to 60s; in the front-end polymerization reaction, the "front edge" moves downward at a constant speed until the polymerization is completed.

[0011] In a preferred embodiment of the present invention, the post-treatment of the front-end polymerization reaction is to remove unreacted monomers and solvents by washing with water, or by directly freeze-drying to remove unreacted monomers and solvents; the number of water washings is 2 to 5 times, the freeze-drying temperature is -40℃ to -80℃, and the freeze-drying time is 24h to 168h.

[0012] Another object of the present invention is to provide a carbon quantum dot gel material based on a front-end polymerization method prepared by any of the above-described preparation methods.

[0013] A method for preparing a composite film of carbon quantum dot gel material based on a front-end polymerization method includes the following steps: Weigh out the biodegradable biopolyester material and the spinning solution solvent, mix them thoroughly and stir evenly to form solution A.

[0014] Weigh out the carbon quantum dot gel material based on the front-end polymerization method and the spinning solvent, mix them thoroughly and stir evenly to form liquid B.

[0015] Liquid A and liquid B are injected into the Y-shaped chip for mixing, and the mixture is obtained at the outlet of the Y-shaped chip.

[0016] After electrospinning the mixture, a composite film of carbon quantum dot gel material obtained by front-end polymerization was obtained.

[0017] In a preferred embodiment of the present invention, the biodegradable biopolyester material in solution A has a mass fraction of 5wt% to 20wt%, and the spinning solvent has a mass fraction of 80wt% to 95wt%, totaling 100%; the carbon quantum dot gel material based on front-end polymerization in solution B has a mass fraction of 1wt% to 5wt%, and the spinning solvent has a mass fraction of 95wt% to 99wt%, totaling 100%.

[0018] In a preferred embodiment of the present invention, the Y-shaped chip has two inlet channels and one outlet channel for mixing solutions. Each inlet channel has a length of 1cm to 8cm, each outlet channel has a length of 1cm to 8cm, and each channel has an inner diameter of 0.2mm to 5mm. The flow rate of the microfluidic pump is set to 0.1mL / h to 10mL / h. The diameter of the needle is 0.5mm to 0.8mm, and the voltage of the high-voltage circuit is 12KV to 25KV. The distance between the needle and the receiver is 10cm to 20cm. The receiver rotation speed is adjusted to 150rpm to 600rpm. The electrospinning time is 1h to 8h.

[0019] Another object of the present invention is to provide a carbon quantum dot gel material and its composite film prepared by any of the above-described preparation methods based on a front-end polymerization method.

[0020] The application of the carbon quantum dot gel composite film based on front-end polymerization method described in this invention in wound dressings.

[0021] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention uses acrylamide, 1-vinyl-2-pyrrolidone, and hydroxypropyl acrylate as monomers. The monomers, citric acid, polyethyleneimine, and the oxidant ammonium persulfate are dissolved in a solvent to obtain a front-end solution. The reducing agent N,N,N′,N′-tetramethylethylenediamine is added to the front-end solution and mixed thoroughly to obtain a mixed solution. The addition of the redox components accelerates the subsequent reaction and releases a large amount of heat to power the thermally initiated process, ensuring that crosslinking occurs in the front-end form. The surface of the mixed solution is heated to induce a reverse front-end polymerization reaction between the monomers, resulting in a carbon quantum dot gel material based on front-end polymerization. This front-end polymerization technology allows for bottom-up in-situ synthesis of carbon quantum gel materials. This reaction mode is rapid and energy-efficient, requiring no continuous heating or stirring, and is easily controlled, enabling wound medical materials to be "made-to-use," ensuring stable performance and no pollution, and exhibiting high sterility and biocompatibility.

[0022] 2. After synthesizing hydrogel carbon quantum dot materials, this invention uses microfluidic electrospinning technology in conjunction with biodegradable biopolyester materials to form a carbon quantum dot gel composite film based on front-end polymerization. This film can be used in wound dressings, further solving the problems of small specific surface area, low porosity, high sterilization and high biocompatibility of hydrogel carbon quantum dot materials when directly used as wound dressings, thus optimizing the effect in wound healing applications. Attached Figure Description

[0023] Figure 1 This is a SEM image of a carbon quantum dot gel composite film based on a front-end polymerization method, using PBAT polyester material as the substrate prepared in Example 1 of the present invention.

[0024] Figure 2 The graphs show the antibacterial properties of the carbon quantum dot gel composite membrane based on front-end polymerization method prepared by PBAT polyester material in Example 1 of the present invention and the PBAT polyester fiber membrane prepared by Comparative Example 1 against *Stellaria media*.

[0025] Figure 3 The fluorescence spectrum of the carbon quantum dot gel composite film based on front-end polymerization method with PBAT polyester material as the substrate prepared in Example 1 of the present invention is shown.

[0026] Figure 4 This is a schematic diagram of the carbon quantum dot gel materials prepared by front-end polymerization method in Examples 1 to 3 of the present invention. Detailed Implementation

[0027] The following detailed description, in conjunction with embodiments of the present invention and accompanying drawings, provides a clear and complete illustration of the technical solutions in these embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0028] It should be noted that all technical terms used in this invention are for the purpose of describing specific embodiments only and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of this invention can be purchased from the market or prepared by existing methods.

[0029] Example 1 A method for preparing carbon quantum dot gel materials based on front-end polymerization includes the following steps: (1) Weigh 2g of acrylamide, 8g of 1-vinyl-2-pyrrolidone, 2g of hydroxypropyl acrylate, 8g of N,N-dimethylformamide, 0.07g of ammonium persulfate, 0.5g of citric acid and 1g of polyethyleneimine and mix them evenly in a container. Weigh 0.07g of N,N,N′,N′-tetramethylethylenediamine and add it to the solution and mix evenly.

[0030] (2) The surface of the above mixed solution was heated at 100°C for a period of time with a soldering iron to induce the front-end polymerization reaction. After observing a stable "front", the heat source was removed. During the polymerization process, the "front" moved downward at a constant speed, and the polymerization was completed after 10 minutes. The polymerized product was placed in a freeze dryer with the drying temperature set at -60°C and the drying time set at 160 hours to remove unreacted monomers and obtain carbon quantum dot gel.

[0031] Example 2 A method for preparing carbon quantum dot gel materials based on front-end polymerization includes the following steps: (1) Weigh 2g of acrylamide, 8g of 1-vinyl-2-pyrrolidone, 2g of hydroxypropyl acrylate, 8g of N,N-dimethylformamide, 0.07g of ammonium persulfate, 0.5g of citric acid and 0.5g of polyethyleneimine and mix them evenly in a container. Weigh 0.07g of N,N,N′,N′-tetramethylethylenediamine and add it to the solution and mix evenly.

[0032] (2) The surface of the above mixed solution was heated at 100°C for a period of time with a soldering iron to induce the occurrence of the front-end polymerization reaction. After observing a stable "front", the heat source was removed. The "front" moved downward at a constant speed, and the polymerization was completed after 8 minutes. The polymerized product was washed repeatedly with deionized water 3 times to obtain carbon quantum dot gel with unreacted monomers removed.

[0033] Example 3 A method for preparing carbon quantum dot gel materials based on front-end polymerization includes the following steps: (1) Weigh 2g of acrylamide, 8g of 1-vinyl-2-pyrrolidone, 2g of hydroxypropyl acrylate, 8g of N,N-dimethylformamide, 0.07g of ammonium persulfate, 0.5g of citric acid, and 1.5g of polyethyleneimine and mix them evenly in a container. Weigh 0.07g of N,N,N′,N′-tetramethylethylenediamine and add it to the solution and mix evenly.

[0034] (2) The surface of the above mixed solution was heated at 100°C for a period of time with a soldering iron to induce the occurrence of the front-end polymerization reaction. After observing a stable "front", the heat source was removed. The "front" moved downward at a constant speed, and the polymerization was completed after 8 minutes. The polymerized product was placed in a freeze dryer with the drying temperature set at -70°C and the drying time set at 120 hours to remove unreacted monomers and obtain carbon quantum dot gel.

[0035] Taking the carbon quantum dot gel material prepared in Example 1 as an example, it was prepared into a composite film, as shown in the following examples: Example 4 A method for preparing a carbon quantum dot gel composite film based on a front-end polymerization method (a carbon quantum dot gel composite film based on PBAT polyester material as the substrate) includes the following steps: (1) Take 1.64g PBAT, 6g DCM, 2g HFIP and 2g DMB and stir at 300rpm for 12h to obtain a uniformly dissolved and dispersed solution A.

[0036] (2) Take 0.8g of carbon quantum dot gel and 9.2g of DMF and stir at 300rpm for 12h to obtain a uniformly dissolved and dispersed solution B.

[0037] (3) Use a 20mL syringe to draw up the spinning solution and install it on the microfluidic pump. The liquid outlet is injected into the two liquid inlets of the Y-shaped chip. Install a 0.5mm diameter needle at the liquid outlet of the Y-shaped chip (the liquid inlet channel length is 1.5cm, the liquid outlet channel is 3cm, and the channel inner diameter is 0.5mm) for liquid dispensing. Install the syringe on the microfluidic pump, set the flow rate of solution A to 6mL / h and solution B to 0.5mL / h, set the distance between the roller and the liquid outlet of the needle to 12cm, turn on the microfluidic pump, set the voltage to 20KV to turn on the high voltage, set the roller speed to 300rpm, and the spinning time to 2h to obtain a carbon quantum dot gel material composite film based on front-end polymerization (a carbon quantum dot gel material composite film based on front-end polymerization with PBAT polyester material as the substrate).

[0038] Example 5 A method for preparing a carbon quantum dot gel composite film (a carbon quantum dot gel composite film based on PBAT polyester material using a front-end polymerization method) comprising the following steps: (1) Take 1.64g PBAT, 6g DCM, 2g HFIP and 2g DMB and stir at 300rpm for 12h to obtain a uniformly dissolved and dispersed solution A.

[0039] (2) Take 0.5g of carbon quantum dot gel and 9.5g of DMF and stir at 300rpm for 12h to obtain a uniformly dissolved and dispersed solution B.

[0040] (3) Use a 20mL syringe to draw up the spinning solution and install it on the microfluidic pump. The liquid outlet is injected into the two liquid inlets of the Y-shaped chip. Install a 0.5mm diameter needle at the liquid outlet of the Y-shaped chip (the liquid inlet channel length is 1.5cm, the liquid outlet channel is 3cm, and the channel inner diameter is 0.5mm) for liquid dispensing. Install the syringe on the microfluidic pump, set the flow rate of solution A to 6mL / h and solution B to 1mL / h, set the distance between the roller and the liquid outlet of the needle to 10cm, turn on the microfluidic pump, set the voltage to 20KV to turn on the high voltage, set the roller speed to 300rpm, and the spinning time to 2h to obtain a carbon quantum dot gel material composite film based on front-end polymerization (a carbon quantum dot gel material composite film based on front-end polymerization with PBAT polyester material as the substrate).

[0041] Example 6 A method for preparing a carbon quantum dot gel composite film (a carbon quantum dot gel composite film based on PBAT polyester material using a front-end polymerization method) comprising the following steps: (1) Take 1.64g PBAT, 6g DCM, 2g HFIP and 2g DMB and stir at 300rpm for 12h to obtain a uniformly dissolved and dispersed solution A.

[0042] (2) Take 0.6g of carbon quantum dot gel and 9.4g of DMF and stir at 300rpm for 12h to obtain a uniformly dissolved and dispersed solution B.

[0043] (3) Use a 20ml syringe to draw up the spinning solution and install it on the microfluidic pump. The liquid outlet is injected into the two liquid inlets of the Y-shaped chip. Install a 0.5mm diameter needle at the liquid outlet of the Y-shaped chip (the liquid inlet channel length is 2cm, the liquid outlet channel is 4cm, and the channel inner diameter is 0.6mm) for liquid dispensing. Install the syringe on the microfluidic pump, set the flow rate of solution A to 8mL / h and solution B to 0.8mL / h, set the distance between the roller and the liquid outlet of the needle to 10cm, turn on the microfluidic pump, set the voltage to 22KV to turn on the high voltage, set the roller speed to 300rpm, and the spinning time to 1.5h to obtain a carbon quantum dot gel material composite film based on front-end polymerization (a carbon quantum dot gel material composite film based on front-end polymerization with PBAT polyester material as the substrate).

[0044] Comparative Example 1 A method for preparing a PBAT polyester fiber membrane includes the following steps: (1) Take 1.64g PBAT, 6g DCM, 2g HFIP and 2g DMB and stir at 300rpm for 12h to obtain a spinning solution that is dissolved and dispersed evenly.

[0045] (2) Use a 20ml syringe to draw up the spinning solution, install a 0.5mm diameter needle for dispensing the solution, install the syringe on the microfluidic pump, set the flow rate to 6mL / h, set the distance between the roller and the dispensing point of the needle to 14cm, turn on the microfluidic pump, set the voltage to 22KV to turn on the high voltage, set the roller speed to 300rpm, and the spinning time to 2h to obtain PBAT polyester fiber membrane.

[0046] Results Analysis Figure 1 This is a SEM image of the carbon quantum dot gel composite film prepared in Example 4 of this invention, using PBAT polyester material as the substrate and based on a front-end polymerization method. The surface morphology of the sample was observed using a field emission scanning electron microscope (S-4800) at an accelerating voltage of 20 kV. Figure 1 The fibrous membrane can be seen, with uniform pore distribution and fiber thickness, and the fiber thickness is about 200 nanometers.

[0047] Figure 2The antibacterial properties of the carbon quantum dot gel composite membrane based on PBAT polyester material prepared in Example 4 of this invention and the PBAT polyester fiber membrane prepared in Comparative Example 1 against *Stellaria media* are shown in the graphs. Specific testing method: The bacterial solution was diluted to 10⁶ CFU / mL with LB liquid medium. The diluted bacterial solution was added to sterilized sample tubes according to the culture system (one sample + 2 mL bacterial solution), and incubated at 37°C for 18 hours. After incubation, 200 μL of co-culture solution was added to each well of a 96-well plate. The OD values ​​of each group were measured at 600 nm using a microplate reader. The antibacterial properties of the carbon quantum dot composite membrane were tested using the OD values ​​and plate coating. Figure 2 It can be seen that the carbon quantum dot gel composite film based on front-end polymerization method has a significant antibacterial effect on *Stellaria media*.

[0048] Figure 3 The fluorescence spectrum of the carbon quantum dot gel composite film based on front-end polymerization method, using PBAT polyester material as the substrate, prepared in Example 4 of this invention, was measured using a Varian Cary Eclipse fluorescence spectrophotometer. Figure 3 As can be seen, the prepared carbon quantum dots exhibit blue fluorescence under ultraviolet light and are excitation-dependent. As the excitation wavelength increases, the fluorescence wavelength also increases, which is consistent with the blue fluorescence characteristics of carbon quantum dots. The optimal excitation wavelength is 360 nm and the emission wavelength is 420 nm. This result proves that the carbon quantum dots were successfully synthesized and have good fluorescence performance.

[0049] Figure 4 These are schematic diagrams of the carbon quantum dot gel materials prepared using front-end polymerization methods in Examples 1 to 3 of this invention. Figure 4 After initiation, as the front-end polymerization reaction proceeds, heat is generated and diffused, producing an in-situ carbon quantum dot hydrogel composite material.

[0050] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

[0051] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for preparing carbon quantum dot gel materials based on front-end polymerization, characterized in that, Includes the following steps: Using acrylamide, 1-vinyl-2-pyrrolidone, and hydroxypropyl acrylate as hydrogel monomers, a mixed solution was obtained by dissolving the hydrogel monomers, carbon quantum dot monomer citric acid, polyethyleneimine, and oxidant ammonium persulfate in a solvent. The reducing agent N,N,N′,N′-tetramethylethylenediamine was added to the mixed solution and stirred rapidly until homogeneous to obtain the front-end polymerization solution; The surface of the front-end polymerization solution is heated and induced to undergo a redox reaction and exothermic reaction, which causes a front-end polymerization reaction between hydrogel monomers, resulting in a carbon quantum dot gel material based on the front-end polymerization method. The solvent is N,N-dimethylformamide; in the mixed solution, the mass fractions of acrylamide are 10 to 20 parts, 1-vinyl-2-pyrrolidone are 30 to 90 parts, hydroxypropyl acrylate is 10 to 20 parts, N,N-dimethylformamide is 30 to 90 parts, ammonium persulfate is 0.05 to 0.8 parts, citric acid is 1 to 20 parts, and polyethyleneimine is 1 to 20 parts. In the front-end polymerization solution, the mass fraction of N,N,N',N'-tetramethylethylenediamine is 0.05 to 0.8 parts; The conditions for heat induction are as follows: after heating for 15 to 60 seconds, the heat source is removed; the front-end polymerization reaction moves downward at a constant rate until polymerization is complete.

2. The carbon quantum dot gel material prepared by the preparation method according to claim 1, based on a front-end polymerization method.

3. A method for preparing a composite film of carbon quantum dot gel material based on a front-end polymerization method, characterized in that, Includes the following steps Weigh out the biodegradable biopolyester material and the spinning solution solvent, mix them thoroughly and stir until homogeneous to form solution A; Weigh out the carbon quantum dot gel material based on the front-end polymerization method as described in claim 2 and the spinning solvent, mix them thoroughly and stir evenly to form liquid B; Liquid A and liquid B are injected into the Y-shaped chip for mixing, and the mixture is obtained at the outlet of the Y-shaped chip. After electrospinning the mixture, a composite film of carbon quantum dot gel material obtained by front-end polymerization was obtained.

4. The method for preparing a composite film of carbon quantum dot gel material based on front-end polymerization according to claim 3, characterized in that, In solution A, the mass fraction of biodegradable biopolyester material is 5wt%~20wt%, and the mass fraction of spinning solvent is 80wt%~95wt%, totaling 100%. In solution B, the mass fraction of carbon quantum dot gel material based on front-end polymerization is 1wt%~5wt%, and the mass fraction of spinning solvent is 95wt%~99wt%, totaling 100%.

5. The method for preparing a composite film of carbon quantum dot gel material based on front-end polymerization according to claim 4, characterized in that, The Y-shaped chip has two inlet channels and one outlet channel for solution mixing. Each inlet channel is 1cm to 8cm long, the outlet channel is 1cm to 8cm long, and the channel inner diameter is 0.2mm to 5mm. The microfluidic pump flow rate is set to 0.1mL / h to 10mL / h. The needle diameter is 0.5mm to 0.8mm, and the voltage is 12KV to 25KV. The distance between the needle and the receiver is 10cm to 20cm. The receiver rotation speed is adjusted to 150rpm to 600rpm. The electrospinning time is 1h to 8h.

6. A composite membrane of carbon quantum dot gel material prepared by the preparation method of claim 5 based on a front-end polymerization method.

7. The application of the composite film of carbon quantum dot gel material based on front-end polymerization method according to claim 6 in the preparation of wound dressings.

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