CN115068670A - Composition combining Fenton reaction antibacterial composite hydrogel and application thereof - Google Patents
Composition combining Fenton reaction antibacterial composite hydrogel and application thereof Download PDFInfo
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Abstract
The invention discloses a composition combining Fenton reaction antibacterial composite hydrogel, which comprises the antibacterial composite hydrogel and hydrogen peroxide, wherein the raw materials of the antibacterial composite hydrogel comprise an antibacterial material and a natural polymer hydrogel base material; the antimicrobial material comprises at least iron-loaded graphene nanoplatelets. The Fenton reaction antibacterial composite hydrogel composition for combined use disclosed by the invention generates a large amount of active oxygen by combining a natural polymer gel material with a Fenton reaction, can safely and efficiently resist bacteria and effectively promote wound healing when being applied to the surface of a wound, and overcomes the defects that the existing wound dressing is single in function, narrow in antibacterial spectrum and easy to stimulate the wound.
Description
Technical Field
The invention relates to the technical field of nano and micro antibacterial, in particular to a composition combining Fenton reaction antibacterial composite hydrogel and application thereof.
Background
Skin wounds are often associated with a risk of infection, and wound dressings are often used clinically to treat wounds. The traditional wound dressings comprise cotton, gauze, bandages and the like, and the wound dressings have wide sources and low cost, but have a plurality of limitations in clinical diagnosis and treatment: firstly, the adhesive is seriously adhered to wound tissues, so that frequent dressing change is required, and the adhesive is easy to adhere to wounds to aggravate the pain of patients during dressing change operation; secondly, gauze dressings such as iodophor gauze cannot completely resist external bacterial infection due to poor sealing performance, and only can provide a physical barrier. With the development of the field of wound treatment, research shows that a moist healing environment can stimulate the secretion of growth factors and provide favorable conditions for wound healing, and the traditional wound dressing does not have the function of providing a moist environment for a wound surface and cannot promote wound repair. The hydrogel is a soft substance with a three-dimensional network structure and high water content, and has good biocompatibility, predictable degradation rate and good elasticity, so that the hydrogel becomes an excellent material for biomedical application, and becomes a research hotspot of biomedical materials in recent years. The dressing can be used for maintaining moist wound healing environment, and promoting autolytic removal of slough and necrotic tissue.
Wound infection is an important factor for delaying wound healing, the wound healing environment is more complicated due to the infection of multiple drug-resistant bacteria, and currently, the clinically used bactericides mainly comprise: silver sulfapyridine, a broad-spectrum bactericide, but silver ions have certain biological toxicity, and granulocytopenia occurs in some patients; iodophor, convenient to use, but has strong volatility, resulting in large dosage and pigmentation on the wound surface; chlorhexidine (chlorhexidine), which has a narrow antimicrobial spectrum; hydrogen peroxide (H) 2 O 2 Solution), a broad-spectrum bactericide, but the clinically used hydrogen peroxide has a high concentration (up to 3%) and is easy to damage normal tissues. In addition, the existing external preparation for treating the wound surface and the antibacterial agent are almost independently used, the treatment mode is generally to firstly kill and clean the wound surface and then use the dressing to promote the wound healing, and the medicine application and the medicine changing process inevitably bring adverse experience to patients and influence the treatment effect. Therefore, the development of a wound dressing which can protect a wound surface from bacterial infection, prevent tissue dehydration, has good air permeability and promotes wound healing is particularly critical.
Disclosure of Invention
The invention aims to provide a composition combined with Fenton reaction antibacterial composite hydrogel, which can protect a wound surface from bacterial infection, prevent tissue dehydration, has good air permeability and has the effect of promoting wound healing.
In order to achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the invention provides a composition combining fenton reaction antibacterial composite hydrogel, which comprises the antibacterial composite hydrogel and hydrogen peroxide, wherein the raw materials of the antibacterial composite hydrogel comprise an antibacterial material and a natural polymer hydrogel base material; the antimicrobial material comprises at least iron-loaded graphene nanoplatelets.
The antibacterial composite hydrogel is combined with low-concentration hydrogen peroxide and applied to the surface of a wound infected by bacteria, and the antibacterial composite hydrogel and the hydrogen peroxide generate Fenton reaction to generate a large amount of active oxygen at the wound, so that the effects of efficient sterilization, infection prevention and wound healing promotion are realized.
Further, the concentration of the hydrogen peroxide is 0.0001-0.1 mol/L.
Further, the mass ratio of the iron-loaded graphene nanosheet to the natural polymer hydrogel substrate is (1:0.1) - (1: 70).
Further, the antibacterial material also comprises other antibacterial materials, and the other antibacterial materials are selected from at least one of nano silver, micro silver, nano copper, micro copper, nano zinc oxide, micro zinc oxide, sodium oxide, silicon oxide and phosphorus oxide.
Further, the natural polymer hydrogel base material is one or more of chitosan, sodium alginate, sodium carboxymethyl cellulose and the like.
Further, the preparation method of the antibacterial composite hydrogel comprises the following steps:
s1: providing reduced graphene oxide nanosheets with dispersant-containing surfaces;
s2: dissolving the reduced graphene oxide nanosheet with the surface containing the dispersing agent and the organic iron salt in an organic solvent, ultrasonically dispersing uniformly, introducing inert gas, heating to 200-300 ℃ in a gradient manner, and reacting to obtain an iron-loaded graphene nanosheet;
s3: adding the iron-loaded graphene nanosheet and the natural polymer hydrogel base material into sterile water, optionally adding other antibacterial materials, fully mixing, adding a cross-linking agent, and stirring to form the gel quickly.
In the iron-loaded graphene nanosheet prepared by the method, the size of iron oxide nanoparticles is small (0.5-10 nm), the particle size distribution is uniform, and the iron oxide nanoparticles are uniformly distributed on the surface of the graphene nanosheet. Therefore, the antibacterial composite hydrogel can be better cooperated with hydrogen peroxide for antibiosis.
Further, in the above method, the mass ratio of the reduced graphene oxide nanoplatelets having a dispersant on the surface thereof to the organic iron salt is (1:1) to (1: 10).
The dispersing agent is one or more of sodium polystyrene sulfate, polyvinylpyrrolidone, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, polyethylene glycol, sodium glycocholate and hexadecyl trimethyl ammonium bromide.
The organic ferric salt is one or more of ferric acetylacetonate, ferric oxalate and ferric citrate.
And the temperature is increased to 270-300 ℃ in a gradient manner to carry out reaction.
The temperature rising rate of the gradient temperature rising is 1-20 ℃/min. The size and the uniformity of the iron oxide nanoparticles can be regulated and controlled by gradient temperature rise, and the size and the uniformity of the iron oxide nanoparticles can be controlled more optimally by the temperature rise rate provided by the invention.
The preparation method of the reduced graphene oxide nanosheet with the surface containing the dispersing agent comprises the following steps:
dispersing the graphene oxide nanosheets in a solvent, adding a dispersing agent and a reducing agent, and reacting under a heating condition.
Further, in the method, the mass ratio of the graphene oxide nanosheet to the dispersant to the reducing agent is 1:1: 1-1: 20: 2.
The reducing agent is hydrazine hydrate or sodium citrate.
The heating reaction is carried out for 24-48 h at 60-150 ℃.
After the reaction, the post-treatment steps of suction filtration and freeze drying are also included; more preferably, the temperature of the freeze-drying is-20 ℃ to-100 ℃.
In a second aspect, the present invention provides an antimicrobial kit comprising the above-mentioned composition in combination with a fenton's reaction antimicrobial composite hydrogel.
In a third aspect, the invention provides an application of the composition of the combined fenton reaction antibacterial composite hydrogel in preparing a medicament for treating skin wound infection or promoting wound healing.
Further, the antibacterial composite hydrogel and hydrogen peroxide are separately used, or simultaneously or sequentially used in combination.
In addition, unless otherwise specified, any range recited herein includes any value between the endpoints and any sub-range defined by any value between the endpoints or any value between the endpoints. The preparation method in the invention is a conventional method unless otherwise specified, and the raw materials used are commercially available from public sources or prepared according to the prior art unless otherwise specified, the percentages are mass percentages unless otherwise specified, and the solutions are aqueous solutions unless otherwise specified.
The invention has the following beneficial effects:
1. the composition of the combined Fenton reaction antibacterial composite hydrogel generates active oxygen by combining the natural polymer gel material with the Fenton reaction, can safely and efficiently resist bacteria and effectively promote wound healing, and overcomes the defects of single function, narrow antibacterial spectrum and easy wound stimulation of the conventional wound dressing.
2. The composition of the combined Fenton reaction antibacterial composite hydrogel provided by the invention is simple in preparation method, mild in preparation conditions, high in biological safety and pollution-free, and can be used as a clinical medical hydrogel dressing.
3. In the composition of the combined Fenton reaction antibacterial composite hydrogel provided by the invention, the antibacterial composite hydrogel has a stable structure and strong practicability, and has higher clinical and market application potentials.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 shows a transmission electron micrograph of iron-loaded graphene nanoplatelets prepared according to example 1;
FIG. 2 is a graph showing the comparison of the bactericidal effect of different materials on Staphylococcus aureus and Escherichia coli in the bactericidal efficiency test of example 1;
FIG. 3 is a graph showing a comparison of the effect of different materials on the healing process of the skin of rats infected with Staphylococcus aureus to the wound in the anti-infection and healing promotion tests of example 1;
figure 4 shows a comparison of the rate of healing of the skin of rats infected with staphylococcus aureus on wounds for different materials in the anti-infection and healing promotion tests of example 1.
Detailed Description
For a further understanding of the invention, preferred embodiments of the invention are described below in conjunction with the examples, but it should be understood that these descriptions are included merely to further illustrate the features and advantages of the invention and are not intended to limit the invention to the claims.
All the raw materials of the present invention are not particularly limited in their purity, and the purity requirements of analytical purity are preferably employed in the present invention.
All the raw materials, sources and abbreviations thereof, of the present invention belong to conventional sources and abbreviations in the art, and are clearly and clearly defined in the field of related uses, and those skilled in the art can obtain the raw materials commercially available or prepared by conventional methods according to the abbreviations and the corresponding uses.
Example 1
The embodiment provides a composition combining Fenton reaction antibacterial composite hydrogel, which consists of composite antibacterial hydrogel and hydrogen peroxide (0.001mol/L), wherein the raw materials of the antibacterial composite hydrogel comprise iron-loaded graphene nanosheets and sodium alginate.
The preparation method of the composite antibacterial hydrogel comprises the following steps:
step 1: adding 100mg of graphene oxide nanosheet into distilled water, carrying out ultrasonic uniform dispersion, adding 1g of polystyrene sodium sulfate and 100mg of hydrazine hydrate, reacting for 24 hours at 100 ℃, and carrying out suction filtration and freeze-drying (-60 ℃) on the obtained product to obtain a reduced graphene oxide nanosheet-polystyrene sodium sulfate compound;
step 2: adding 100mg of reduced graphene oxide nanosheet-polystyrene sodium sulfate compound and 200mg of ferric acetylacetonate into 100mL of tetraethylene glycol, ultrasonically dispersing uniformly, introducing argon gas for protection, heating the solution to 300 ℃ at the speed of 5 ℃/min, centrifuging (the centrifugal speed is 1000rpm) after the reaction is finished, and removing supernatant to obtain the iron-loaded graphene nanosheet;
and step 3: adding the iron-loaded graphene nanosheets (100mg) obtained in the step 2 and 1g of sodium alginate into 10mL of sterile water, fully mixing and dissolving, adding 50mg of calcium oxide, and rapidly gelling under mechanical stirring to obtain composite antibacterial hydrogel;
as can be seen from fig. 1, the particle size of the iron oxide nanoparticles is between about 0.5nm and 2nm, and the iron oxide nanoparticles are uniformly loaded on the surface of the graphene nanosheets, and the iron-loaded graphene nanosheets can effectively prevent the iron oxide nanoparticles from leaking and losing in the hydrogel system.
Effect testing
(1) And (3) sterilization efficiency:
the combined Fenton reaction antibacterial composite hydrogel composition (D) and the composite antibacterial hydrogel (B) prepared in the example and 0.001mol/L H 2 O 2 (C) 200mg of each of the above-mentioned bacteria was mixed with 10mL of the bacteria at a concentration of 1X 10 5 The bacterial solutions of Staphylococcus aureus (MRSA) and Escherichia coli (E.coli) of CFU were co-cultured in a shaker at 37 deg.C for 1.5 hr, and 200mg of physiological saline was used as a control group (A) for the sameAnd (5) carrying out experiments. After the co-culture is finished, 100 mu L of co-culture solution is uniformly smeared on an LB culture plate for each group, the culture plate is placed in an oven at 37 ℃ upside down for co-culture for 36 hours, the growth condition of bacteria in each group is observed and photographed and recorded, and the result is shown in figure 2.
As can be seen from FIG. 2, H was present at a concentration of 0.001mol/L 2 O 2 And the two groups of single components of the composite antibacterial hydrogel have no obvious growth inhibition effect on MRSA and E.Coli and still have a large amount of bacteria growth; the bacterial solution treated with the composition combining the fenton reaction antibacterial hydrogel showed almost no bacterial growth on the culture plate, indicating that the iron-loaded graphene nanoplatelets and H in the composition combining the fenton reaction antibacterial hydrogel 2 O 2 After the combined action, a large amount of active oxygen is generated, and the composite antibacterial hydrogel can be efficiently sterilized, namely the composite antibacterial hydrogel is at low concentration H 2 O 2 Has good antibacterial effect when in use.
(2) Infection resistance and healing promotion:
after anesthetizing 10 adult male SD rats, the back hair was removed, two circular wounds with a diameter of about 1cm were cut on the back using a sterile surgical scissors, the wounds were cut to a depth of total skin excision, i.e., from the skin surface to the muscle layer of the rat, and then the wounds were infected with MRSA (concentration of 106CFU) using a sterile swab dip. Selecting 10 rats, and smearing 100mg of the composition of the combined Fenton reaction antibacterial hydrogel in the embodiment on the wound; the other 10 rats were sprayed with an equal amount of physiological saline as a control group. And respectively observing and photographing the fourth day, the sixth day, the eighth day, the tenth day and the twelfth day, recording the wound healing area, and calculating the wound healing rate, wherein the result is shown in the figures 3-4.
As can be seen from fig. 3, the wounds of rats treated with the composition in combination with the fenton-reaction antibacterial hydrogel healed gradually with time, and at the twelfth day, obvious signs of healing appeared and new epidermis was significantly regenerated; in contrast, the skin wounds of the control group had smaller healing areas after twelve days and significant wound inflammation was present.
As can be seen from fig. 4, the healing rates of the wounds treated with the composition combined with fenton's reaction antibacterial hydrogel were significantly higher than those of the control group on days 4, 6, 8, 10 and 12, and the healing rate was almost 100% on day 12 and about 70% in the control group. The above results show that: the composition combined with the Fenton reaction antibacterial composite hydrogel has good antibacterial and wound healing promoting functions.
Example 2
The embodiment provides a composition of a combined Fenton reaction antibacterial composite hydrogel, which consists of the composite antibacterial hydrogel and hydrogen peroxide (0.001mol/L), wherein the raw materials of the antibacterial composite hydrogel comprise iron-loaded graphene nanosheets and sodium carboxymethylcellulose.
The preparation method of the composite antibacterial hydrogel comprises the following steps:
step 1: adding 100mg of graphene oxide nanosheet into distilled water, carrying out ultrasonic uniform dispersion, adding 500mg of polystyrene sodium sulfate and 100mg of hydrazine hydrate, reacting for 24 hours at 100 ℃, and carrying out suction filtration and freeze-drying (-60 ℃) on the obtained product to obtain a reduced graphene oxide nanosheet-polystyrene sodium sulfate compound;
step 2: adding 100mg of reduced graphene oxide nanosheet-polystyrene sodium sulfate compound and 500mg of ferric acetylacetonate into 100mL of tetraethylene glycol, ultrasonically dispersing uniformly, introducing argon gas for protection, heating the solution to 300 ℃ at the speed of 5 ℃/min, centrifuging (the centrifugal speed is 1000rpm) after the reaction is finished, and removing supernatant to obtain the iron-loaded graphene nanosheet;
and step 3: adding the iron-loaded graphene nanosheet (200mg) obtained in the step 2 and 2g of sodium carboxymethylcellulose into 10mL of sterile water, fully mixing and dissolving, adding 100mg of calcium chloride, and quickly gelling under mechanical stirring to obtain a composite antibacterial hydrogel;
effect testing
(1) And (3) sterilization efficiency:
in vitro antibacterial tests prove that the composition of the combined Fenton reaction antibacterial hydrogel prepared in the embodiment has a more obvious growth inhibition effect on MRSA and E.Coli compared with the composite antibacterial hydrogel and 0.001mol/L hydrogen peroxide.
(2) Infection resistance and healing promotion:
the experiment of rat infected wound healing (the experimental process is the same as that of example 1), the fenton reaction antibacterial hydrogel prepared by the embodiment can effectively prevent wound infection and promote wound healing.
Comparative example 1
The embodiment provides a composition combining Fenton reaction antibacterial composite hydrogel, which consists of composite antibacterial hydrogel and hydrogen peroxide (0.001mol/L), wherein the raw materials of the antibacterial composite hydrogel comprise iron oxide nanoparticles and sodium alginate.
The preparation method of the composite antibacterial hydrogel comprises the following steps:
step 1: adding 200mg of iron acetylacetonate into 100mL of tetraethylene glycol, performing ultrasonic dispersion uniformly, introducing argon for protection, heating the solution to 300 ℃ at the speed of 5 ℃/min, centrifuging (the centrifugal speed is 1000rpm) after the reaction is finished, and removing supernatant to obtain iron oxide nanoparticles;
step 2: adding the ferric oxide nanoparticles (50mg) obtained in the step 1 and 1g of sodium alginate into 10mL of sterile water, fully mixing and dissolving, adding 50mg of calcium oxide, and quickly forming gel under mechanical stirring to obtain composite antibacterial hydrogel;
the observation of the morphology of the hydrogel proves that the iron oxide nanoparticles in the composite antibacterial hydrogel prepared by the embodiment are not uniformly dispersed and are easy to agglomerate, and finally deposit at the bottom of the hydrogel.
Effect testing
And (3) sterilization efficiency:
in vitro antibacterial tests prove that the composite antibacterial hydrogel prepared by the embodiment has an obvious bactericidal effect under the action of 0.001mol/L hydrogen peroxide (the test process is the same as that of the embodiment 1). The experiments show that the ferric oxide nanoparticles can endow hydrogel with good bactericidal performance after being contacted with hydrogen peroxide, but the pure ferric oxide nanoparticles have poor water solubility, poor dispersion effect in a hydrogel system and easy loss and leakage, and need to be loaded on the surface of graphene to improve the stability of the graphene.
Comparative example 2
The embodiment provides a composition combining Fenton reaction antibacterial composite hydrogel, which consists of composite antibacterial hydrogel and hydrogen peroxide (3%), wherein the raw materials of the antibacterial composite hydrogel comprise iron-loaded graphene nanosheets and sodium alginate.
The preparation method of the composite antibacterial hydrogel comprises the following steps:
step 1: adding 100mg of graphene oxide nanosheet into distilled water, carrying out ultrasonic uniform dispersion, adding 1g of polystyrene sodium sulfate and 100mg of hydrazine hydrate, reacting for 24 hours at 100 ℃, and carrying out suction filtration and freeze drying (at (-60 ℃) on the obtained product to obtain a reduced graphene oxide nanosheet-polystyrene sodium sulfate compound;
step 2: adding 100mg of reduced graphene oxide nanosheet-polystyrene sodium sulfate compound and 200mg of ferric acetylacetonate into 100mL of tetraethylene glycol, ultrasonically dispersing uniformly, introducing argon for protection, heating the solution to 300 ℃ at the speed of 5 ℃/min, centrifuging (the centrifugal speed is 1000rpm) after the reaction is finished, and removing supernatant to obtain the iron-loaded graphene nanosheet;
and step 3: and (3) adding the iron-loaded graphene nanosheet (100mg) obtained in the step (2) and 1g of sodium alginate into 10mL of sterile water, fully mixing and dissolving, adding 50mg of calcium oxide, and quickly forming gel under mechanical stirring to obtain the composite antibacterial hydrogel.
Effect testing
And (3) sterilization efficiency:
in vitro antibacterial tests prove that the composition of the combined Fenton reaction antibacterial hydrogel prepared in the embodiment has more obvious growth inhibition effect on MRSA and E.Coli compared with the pure composite antibacterial hydrogel; but also has obvious growth inhibition effect on MRSA and E.Coli by high-concentration hydrogen peroxide (3 percent). The experiment of healing the infected wound of the rat proves that the composition of the combined Fenton reaction antibacterial hydrogel prepared in the embodiment can effectively prevent the infection of the wound, but the combined use of the composition and high-concentration hydrogen peroxide (3%) can cause the wound of the skin of the rat to be burnt, even damage the surrounding normal tissues and can not promote the wound healing.
Comparative example 3
The embodiment provides a composition combining Fenton reaction antibacterial composite hydrogel, which consists of composite antibacterial hydrogel and hydrogen peroxide (0.001mol/L), wherein the raw materials of the antibacterial composite hydrogel comprise iron-loaded graphene nanosheets and sodium alginate.
The preparation method of the composite antibacterial hydrogel comprises the following steps:
step 1: adding 100mg of graphene oxide nanosheet into distilled water, uniformly dispersing by ultrasonic waves, adding 1g of polystyrene sodium sulfate and 100mg of hydrazine hydrate, reacting for 24 hours at 100 ℃, and performing suction filtration and freeze-drying (-60 ℃) on the obtained product to obtain a reduced graphene oxide nanosheet-polystyrene sodium sulfate compound;
step 2: adding 100mg of reduced graphene oxide nanosheet-polystyrene sodium sulfate compound and 200mg of ferric acetylacetonate into 100mL of tetraethylene glycol, ultrasonically dispersing uniformly, introducing argon gas for protection, rapidly heating the solution to 300 ℃ within 10 minutes, centrifuging (the centrifugal speed is 1000rpm) after the reaction is finished, and removing supernatant to obtain the iron-loaded graphene nanosheet;
and step 3: and (3) adding the iron-loaded graphene nanosheet (100mg) obtained in the step (2) and 1g of sodium alginate into 10mL of sterile water, fully mixing and dissolving, adding 50mg of calcium oxide, and quickly forming gel under mechanical stirring to obtain the composite antibacterial hydrogel.
The observation of the morphology of the iron-loaded graphene nanosheet proves that the iron oxide nanoparticles prepared in the embodiment are uneven in size, have the particle size of 20-500nm, and are relatively low in loading efficiency on the graphene nanosheet.
Effect testing
And (3) sterilizing efficiency:
in vitro antibacterial tests prove that the composite antibacterial hydrogel prepared in the embodiment has a poor effect of sterilizing MRSA and E.Coli under the action of 0.001mol/L hydrogen peroxide (the test process is the same as that of the example 1). The experiment shows that the iron oxide nanoparticles prepared by non-gradient heating are too large and uneven in size, the loading efficiency of the iron oxide nanoparticles on graphene nanosheets can be greatly reduced, and accordingly the Fenton reaction efficiency is low and the sterilization effect is poor.
It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and it will be obvious to those skilled in the art that other variations or modifications may be made on the basis of the above description, and all embodiments may not be exhaustive, and all obvious variations or modifications may be included within the scope of the present invention.
Claims (10)
1. The composition combined with Fenton reaction antibacterial composite hydrogel is characterized by comprising antibacterial composite hydrogel and hydrogen peroxide, wherein the raw materials of the antibacterial composite hydrogel comprise an antibacterial material and a natural polymer hydrogel base material; the antimicrobial material comprises at least iron-loaded graphene nanoplatelets.
2. The composition of the antibacterial composite hydrogel combining Fenton's reaction according to claim 1, wherein the concentration of the hydrogen peroxide is 0.0001-0.1 mol/L.
3. The composition of the combined Fenton reaction antibacterial composite hydrogel according to claim 1, wherein the mass ratio of the iron-supported graphene nanosheets to the natural polymer hydrogel substrate is 1: 0.1-1: 70.
4. The composition of the combined fenton reaction antibacterial composite hydrogel according to claim 1, wherein the antibacterial material further comprises other antibacterial materials selected from at least one of nano silver, micro silver, nano copper, micro copper, nano zinc oxide, micro zinc oxide, sodium oxide, silicon oxide and phosphorus oxide;
preferably, the natural polymer hydrogel base material is one or more of chitosan, sodium alginate, sodium carboxymethyl cellulose and the like.
5. The composition of the combined Fenton reaction antibacterial composite hydrogel according to claim 1, wherein the preparation method of the antibacterial composite hydrogel comprises the following steps:
s1: providing reduced graphene oxide nanosheets with dispersant-containing surfaces;
s2: dissolving the reduced graphene oxide nanosheet with the surface containing the dispersing agent and the organic iron salt in an organic solvent, ultrasonically dispersing uniformly, introducing inert gas, heating to 200-300 ℃ in a gradient manner, and reacting to obtain an iron-loaded graphene nanosheet;
s3: adding the iron-loaded graphene nanosheet and the natural polymer hydrogel base material into sterile water, optionally adding other antibacterial materials, fully mixing, adding a cross-linking agent, and stirring to quickly form the gel.
6. The composition of the antibacterial composite hydrogel combining Fenton reaction according to claim 5, wherein the mass ratio of the reduced graphene oxide nanosheets with the surfaces containing the dispersing agent to the organic iron salt is 1: 1-1: 10;
preferably, the dispersant is one or more of sodium polystyrene sulfate, polyvinylpyrrolidone, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, polyethylene glycol, sodium glycocholate and hexadecyl trimethyl ammonium bromide;
preferably, the organic iron salt is one or more of ferric acetylacetonate, ferric oxalate and ferric citrate;
preferably, the temperature is increased to 270-300 ℃ in a gradient manner to carry out the reaction; more preferably, the temperature rise rate of the gradient temperature rise is 1 ℃/min to 20 ℃/min.
7. The composition of the antibacterial composite hydrogel combined with Fenton reaction according to claim 5, wherein the preparation method of the reduced graphene oxide nanosheets with the surfaces containing the dispersing agent comprises the following steps:
dispersing the graphene oxide nanosheets in a solvent, adding a dispersing agent and a reducing agent, and reacting under a heating condition.
8. The composition of the combined Fenton reaction antibacterial composite hydrogel according to claim 7, wherein the mass ratio of the graphene oxide nanosheets to the dispersing agent to the reducing agent is 1:1: 1-1: 20: 2;
preferably, the reducing agent is hydrazine hydrate or sodium citrate;
preferably, the heating reaction is carried out for 24 to 48 hours at a temperature of between 60 and 150 ℃;
preferably, the reaction is followed by a post-treatment step of suction filtration and freeze drying; more preferably, the temperature of the freeze-drying is-20 ℃ to-100 ℃.
9. An antibacterial kit comprising the composition for a combined Fenton's reaction antibacterial composite hydrogel according to any one of claims 1 to 8.
10. Use of a composition of the combined Fenton's reaction antibacterial composite hydrogel according to any one of claims 1 to 8 in the preparation of a medicament for treating skin wound infection or promoting wound healing;
preferably, the antibacterial composite hydrogel and hydrogen peroxide are used separately, simultaneously or sequentially.
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