CN113230448B

CN113230448B - Gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, and preparation method and application thereof

Info

Publication number: CN113230448B
Application number: CN202110548620.9A
Authority: CN
Inventors: 黄建永; 田卓灵; 苏醒; 解文月
Original assignee: Peking University
Current assignee: Peking University
Priority date: 2021-05-19
Filing date: 2021-05-19
Publication date: 2022-03-25
Anticipated expiration: 2041-05-19
Also published as: CN113230448A

Abstract

A gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, and its preparation method and application are provided. The hydrogel comprises gelatin, hydroxyethyl urea and punicalagin, the hydroxyethyl urea is added into a gelatin aqueous solution by adopting a one-pot mixing method, and the gelatin is prevented from self-forming hydrogen bonds at low temperature to self-gelatinize by utilizing the interaction of the gelatin and the hydroxyethyl urea, so that the low-temperature injectability is realized; then, punicalagin is added, and the interaction of the strong hydrogen bond of the punicalagin and the gelatin is utilized to form a main network. The hydrogel is used as a multifunctional wound adhesive, is stable in adhesion in air, has the adhesion strength of 45.77kPa within 10 minutes, and still has the adhesion strength of 40kPa after 14 days. The hydrogel has the functions of diminishing inflammation, resisting bacteria, promoting healing obviously and integrating the adhering function and biological function. The hydrogel is sealed in a syringe or a hose, stored at low temperature and directly used for surgical adhesion or mucous membrane repair, or coated on a substrate, and the viscosity of the hydrogel is stimulated by medical alcohol after the hydrogel is dried, so that the hydrogel can be used for daily bruise.

Description

Gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, and preparation method and application thereof

Technical Field

The invention relates to the technical field of biomedical materials, in particular to gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel with the viscosity excited by medical alcohol, a preparation method and application thereof.

Background

In recent years, many emerging biomedical materials have been used for wound adhesion or wound protection, including porous sponges, electrospun membranes, biofilms, hydrogels, and the like, most of which are gelatin-based in view of biocompatibility.

Based on the influence of the style of the finished product of the preparation, the material has no injectability except hydrogel, cannot be applied to minimally invasive or non-invasive surgery, and increases the risk of the surgery. However, gelatin-based hydrogels are often stored at low temperature and are costly to transport, and they form gels by self-hydrogen bonding at low temperature, and they also require heating to recover their injectable properties, increasing the time cost.

In addition, the biological function and the bonding performance of the wound dressing are difficult to organically unify by the materials, and the materials are often bonded with the wound by gauze or viscous paint, so that the operation difficulty is increased.

In addition, gelatin-based materials are highly susceptible to bacterial growth, and thus it is desirable to impart antimicrobial properties to the materials. Wounds or wound surfaces are often accompanied by inflammatory reactions, thus imparting anti-inflammatory capabilities to the material is beneficial in promoting self-healing of the injured tissue.

In conclusion, there is a need to develop a gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel which can adapt to daily life, is convenient to process and transport, and can realize in vivo and in vitro commercialization in various forms, and a preparation method thereof.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, a preparation method and application thereof.

In order to achieve the above object, the present invention provides a gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, comprising gelatin, hydroxyethyl urea and punicalagin, wherein: adding hydroxyethyl urea into gelatin water solution by adopting a one-pot mixing method, and realizing low-temperature injectability by utilizing the hydrogen bond interaction of gelatin and hydroxyethyl urea; then adding punicalagin, and forming a main network by utilizing the strong hydrogen bond interaction of the punicalagin and the gelatin to obtain the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel with the viscosity excited by medical alcohol.

In the scheme, the gelatin and the hydroxyethyl urea are in hydrogen bond interaction, so that the hydroxyethyl urea and the gelatin are tightly combined, the gelatin is prevented from self-forming hydrogen bonds at low temperature to self-gelatinize, and low-temperature injectability is realized; after the hydroxyethyl urea is tightly combined with the gelatin, the mass fraction of the hydrogel is 5-16%.

In the scheme, the main network is formed by the interaction of the gelatin and the hydrogen bonds of the punicalagin, the mass fraction of the gelatin is 2.5%, the mass fraction of the punicalagin is 50% -61%, and both the gelatin and the punicalagin provide viscosity.

In order to achieve the other object, the invention also provides a preparation method of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, which adopts a one-pot mixing method and comprises the following steps: taking a certain amount of gelatin aqueous solution, adding hydroxyethyl urea into the gelatin aqueous solution, uniformly mixing, adding punicalagin, and fully stirring to obtain the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel.

In the scheme, the certain amount of gelatin aqueous solution is 0.5-1 mL of 2-15% gelatin aqueous solution.

In the scheme, 0.15-0.3 g of hydroxyethyl urea is added into the gelatin aqueous solution, and after the hydroxyethyl urea and the gelatin are fully combined, the gelatin is prevented from self-forming hydrogen bonds at low temperature to self-gelatinize.

In the scheme, the addition of the punicalagin is to add excessive punicalagin, so that the punicalagin and hydroxyethyl urea fully compete, and the punicalagin and gelatin are combined to form a main network. The mass of the punicalagin is 0.95-1.2 g.

In order to achieve the further purpose, the invention also provides application of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel in medical treatment.

In the scheme, the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel is used as a multifunctional wound adhesive, is sealed in an injector or a hose, is stored at a low temperature, is directly used for surgical bonding or mucous membrane repair without thawing after being taken out, or is uniformly coated on a substrate, is activated by medical alcohol after being dried, and is used as daily bruise.

According to the technical scheme, the invention has the beneficial effects that:

1. the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention is prepared by adopting a one-pot mixing method, hydroxyethyl urea is combined with gelatin at room temperature, and excessive punicalagin and the gelatin form hydrogen bonds to form a network, so that the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel with the viscosity excited by medical alcohol is obtained.

2. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention has the advantages that the adhesiveness disappears after being dried, the adhesiveness can be excited by medical alcohol, the process can be repeated, and the formed adhesive can be stable for more than 14 days.

3. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention is used as a multifunctional wound adhesive, has low-temperature injectability, can be directly used for covering and repairing wound surfaces in vivo without heating after the preparation is transported and stored, and saves the operation preparation time. And can be used for minimally invasive or non-invasive surgery, and reduce the surgical risk.

4. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention is used as a multifunctional wound adhesive, has repeated adhesion performance, can be coated on a substrate, can remove the adhesion after being dried, can restore the adhesion after being used for treating a wound by medical alcohol, and has the adhesion strength of 25.3kPa/s, which is 2.5-10 times that of the conventional commercial adhesive bandage. The viscosity can be removed after the second drying, and the viscosity can be excited again when encountering medical alcohol, and the steps are repeated.

5. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention has excellent antibacterial performance as a multifunctional wound adhesive. When escherichia coli e.coli and staphylococcus aureus s.aureus selected in the experiment were used as pathogenic bacteria models, the hydrogel formulation showed significant antibacterial ability.

6. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention is used as a multifunctional wound adhesive and has good cell compatibility, anti-inflammatory and antioxidant properties.

7. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention can be rapidly degraded in vivo as a multifunctional wound adhesive, and can be degraded to 20% in 4 days.

8. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention is used as a multifunctional wound adhesive, the preparation method is simple and convenient, and the hydrogel has multiple processability, and after the preparation is finished, the hydrogel can be used for repairing the mucous membrane in vivo and the wound of skin.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a flow chart of a method for preparing a gelatin-based cryo-injectable anti-inflammatory and anti-bacterial adhesive hydrogel according to an embodiment of the present invention.

FIG. 2 is an infrared spectrum of a gelatin-based cryo-injectable anti-inflammatory and anti-microbial adhesive hydrogel in accordance with an embodiment of the present invention.

FIG. 3 is a graph of data on the adhesion of gelatin-based cryo-injectable anti-inflammatory and anti-microbial adhesive hydrogel to the surface of medical alcohol-treated pigskin at room temperature for various periods of time in accordance with an embodiment of the present invention.

FIG. 4 is a graph showing the comparison of the adhesive strength of a gelatin-based cryo-injectable anti-inflammatory and antibacterial adhesive hydrogel according to an embodiment of the present invention with that of a currently commercially available band-aid.

FIG. 5 is a graph showing data on the long-term stable adhesion of a gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to an embodiment of the present invention.

Figure 6 is a graph of data for the adhesion of gelatin-based cryo-injectable anti-inflammatory and anti-microbial adhesive hydrogels with different viscera, in accordance with embodiments of the present invention.

FIG. 7 is a graph showing the antibacterial effect of a gelatin-based cryo-injectable anti-inflammatory and antibacterial adhesive hydrogel in accordance with an embodiment of the present invention.

FIG. 8 is a graph of in vitro L929 cytotoxicity test of gelatin-based cryo-injected anti-inflammatory antimicrobial cohesive hydrogel leach liquor in accordance with an embodiment of the present invention.

FIG. 9 is a graph of in vitro degradation time of a gelatin-based cryo-injectable anti-inflammatory and anti-microbial adhesive hydrogel in accordance with an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings.

The common gelatin-based hydrogel material forms gel by self-hydrogen bonding of gelatin after being stored at room temperature or under refrigeration, the injectable performance can be recovered by heating, and the gelation concentration of the gelatin-based hydrogel material is only 1.2% w/w, which is unfavorable for practical application. The key for solving the problem of low-temperature self-gelling of the gelatin is to prevent the formation of hydrogen bonds of the gelatin. The hydroxyethyl urea is used as a small molecule and has two N and one-OH, and the combination of the hydroxyethyl urea and the gelatin can effectively prevent the formation of hydrogen bonds between the gelatin and the gelatin, so that the gelatin has the low-temperature injectable performance.

Punicalagin is an extract from pomegranate rind, the main structure of the punicalagin is a gallic acid structure, the punicalagin has an o-phenolic dihydroxy structure similar to dopamine which is a main viscous substance in mussels, three hydroxyl groups are arranged on a benzene ring, and a biphenyl structure provides a stronger conjugation effect, so that the adhesion performance of the punicalagin is better than that of dopamine. The punicalagin also has certain oxidation resistance, anti-inflammatory effect and antibacterial property, can remove free radicals at wounds, can inhibit wound infection, and can limit inflammatory reaction of the wounds, thereby more effectively promoting wound repair. The numerous hydroxyl groups of punicalagin readily hydrogen bond with gelatin to form a physically cross-linked hydrogel, with the remaining exposed hydroxyl groups providing viscosity. The adhesive wound dressing is smeared on a substrate, the adhesiveness disappears after drying, the packaging and the transportation are convenient, and the adhesiveness can be stimulated by 75 percent alcohol for use.

The embodiment of the invention provides a gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, a preparation method and application thereof in medical treatment. The multifunctional specific biological adhesive hydrogel provided by the embodiment of the invention comprises gelatin, hydroxyethyl urea and punicalagin, wherein the hydroxyethyl urea is added into a gelatin aqueous solution by adopting a one-pot mixing method, and low-temperature injectability is realized by utilizing the hydrogen bond interaction of the gelatin and the hydroxyethyl urea; then adding punicalagin, and forming a main network by utilizing the strong hydrogen bond interaction of the punicalagin and the gelatin to obtain the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel with the viscosity excited by medical alcohol.

In the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the embodiment of the invention, the hydrogen bond interaction between the gelatin and the hydroxyethyl urea enables the hydroxyethyl urea and the gelatin to be tightly combined, prevents the gelatin from self-forming hydrogen bonds at low temperature to self-gelatinize, and realizes low-temperature injection; after the hydroxyethyl urea is tightly combined with the gelatin, the mass fraction of the hydrogel is 5-16%.

In the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the embodiment of the invention, the main network is formed by the mutual action of the gelatin and the punicalagin through hydrogen bonds, the mass fraction of the gelatin is 2.5%, the mass fraction of the punicalagin is 50% -61%, and both the gelatin and the punicalagin provide adhesiveness.

Based on the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel of the embodiment, the embodiment of the invention also provides a preparation method of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, as shown in fig. 1, the method adopts a one-pot mixing method, and specifically comprises the following steps:

step 1: taking a certain amount of gelatin water solution, adding hydroxyethyl urea into the gelatin water solution, and uniformly mixing;

step 2: adding punicalagin, and stirring to obtain gelatin-based low-temperature injection antiinflammatory antibacterial viscous hydrogel.

In the step 1, the certain amount of gelatin aqueous solution is 0.5-1 mL of 2-15% gelatin aqueous solution, and optionally 0.5mL of 10% gelatin aqueous solution. The step of adding hydroxyethyl urea into the gelatin aqueous solution is to add 0.15-0.3 g of hydroxyethyl urea into the gelatin aqueous solution, optionally add 0.25g of hydroxyethyl urea, and prevent gelatin from self-forming hydrogen bonds at low temperature and self-gelling after the hydroxyethyl urea and the gelatin are fully combined.

In the step 2, the punicalagin is added in excess, for example, the mass of the punicalagin can be 0.95-1.2 g, so that the punicalagin and hydroxyethyl urea fully compete, and the punicalagin and gelatin are combined to form a main network.

Further, the embodiment of the invention also provides application of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel in medical treatment. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the embodiment of the invention is used as a multifunctional wound adhesive, is sealed in an injector or a hose, is stored at a low temperature, is directly used for surgical adhesion or mucosa repair without thawing after being taken out, or is uniformly coated on a substrate, is activated by medical alcohol after being dried in the air, and is used as daily bruise.

The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel provided by the invention, the preparation method and the application thereof in medical treatment are explained in detail by combining specific embodiments.

Example 1: preparation and performance test of gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel

In this example, the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel is prepared by first mixing 0.5mL of 10% gelatin solution with 0.25g of hydroxyethyl urea, and then adding 1.2g of punicalagin to the mixture and further mixing the mixture uniformly, so as to obtain the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel with the viscosity activated by medical alcohol.

The interaction of the components in the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel is analyzed by infrared spectroscopy and a scanning electron microscope, as shown in fig. 2, and fig. 2 is an infrared spectrum of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to the embodiment of the invention. Comparing the infrared spectra of different substances shows that G-5HU-P (namely the gelatin-based low-temperature injection anti-inflammatory and antibacterial viscous hydrogel of the embodiment of the invention, G represents gelatin, HU represents hydroxyethyl urea, and P represents punicalagin) has low-temperature injectability. Both are 3290cm^-1Nearby absorption shows that both the two have hydrogen bond interaction with gelatin, and the absorption peak position of G-5HU-P is 3291cm^-1The concentration of G-P (G for gelatin and P for punicalagin) was 3292cm^-1A slight blue shift occurred indicating that the prior addition of hydroxyethyl urea interacts strongly with gelatin hydrogen bonds than punicalagin interacts strongly with gelatin. G-P is 1637cm^-1There is absorption, which is the oscillation of the amide bond when beta-sheet occurs in gelatin. G-5HU-P is at 1641cm^-1There is absorption, which is the absorption peak position of amide bond when gelatin presents random coil conformation. The gelation ability of gelatin is positively correlated with the occurrence of beta sheet and alpha helix and negatively correlated with the occurrence of random coil conformation. Thus, it can be shown that the hydroxyethyl urea in G-5HU-P of the present example disrupts the occurrence of gelatin beta sheet, thereby providing G-5HU-P with low temperature injectability.

The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel was evaluated for its adhesive properties using a STS10N universal tester. The experimental test temperature was 25 ℃, the load force was 10N, and the tensile rate was 5 mm/min. Preparing the pigskin with the length of 20mm, the width of 10mm and the thickness of 2mm by adopting a fresh pigskin preparation procedure specified by a pharmaceutical industry standard YY/T0729.1-2009, and smearing 75% of medical alcohol on the surface of the pigskin. In the air, the area is 10X 10mm²The wound adhesive (namely the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel in the embodiment of the invention) is prepared by overlapping two pigskins, pressing for 1min, 2min, 5min and 10min respectively, then carrying out adhesion capability test by using a shearing model, repeatedly measuring each group of samples for at least three times, and recording the stress-strain curve. As shown in fig. 3, fig. 3 is a graph showing the adhesion data of gelatin-based cryo-injectable anti-inflammatory and anti-bacterial adhesive hydrogel according to an embodiment of the present invention on the surface of pigskin treated with medical alcohol at room temperature for various times. The adhesive strength of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel increases with the increase of the pressing time. The bonding strength can reach 45.77kPa after 10 min. In order to evaluate the practical application of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel, the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel is coated on non-woven fabrics, and is stored after being dried. Preparing pigskin with length of 20mm, width of 10mm and thickness of 2mm, smearing 75% medical alcohol or artificial sweat on the surface of pigskin, and covering with 10 × 10mm²The 3M-Nexcare Band-Aid, the Band-Aid and the wound dressing are pasted on the surface of the pigskin for 1min after being dried, the adhesive capacity test is carried out by utilizing a shearing model, each group of samples is repeatedly tested for at least three times, and the strain stress curve of each group of samples is recorded. As shown in fig. 4, fig. 4 is a graph comparing the adhesive strength of the gelatin-based cryo-injection anti-inflammatory and antibacterial adhesive hydrogel according to the embodiment of the present invention with that of the currently commercially available band-aid, and it can be seen that the gelatin-based cryo-injection anti-inflammatory and antibacterial adhesive hydrogel according to the embodiment of the present invention has the highest adhesive capacity.

To evaluate the stable adhesive ability of the gelatin-based low-temperature injection antiphlogistic and antibacterial adhesive hydrogel according to the embodiment of the present invention, pig skin having a length of 20mm, a width of 10mm and a thickness of 2mm was prepared, 75% medical alcohol was coated on the surface of the pig skin, and the area of the gel was 10X 10mm²The gelatin-based low-temperature injectionThe adhesive tape after the anti-inflammatory and antibacterial adhesive hydrogel is dried is attached to the surface of the pigskin, and after the adhesive tape is pressed for 1min, the adhesive data of 1 day, 7 days and 14 days are tested. Preparing pigskin with length of 20mm, width of 10mm and thickness of 2mm, and smearing 75% medical alcohol on the surface of pigskin. In the air, the area is 10X 10mm²The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel is used for overlapping two pigskins, and after 1min of pressing, the adhesive data of 1 day, 7 days and 14 days are tested. As shown in FIG. 5, FIG. 5 is a graph showing data of the long-term stable adhesion of gelatin-based, low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to an embodiment of the present invention, both tests having a high adhesive strength of about 40kPa for 14 days.

To evaluate the potential of the gelatin-based cryo-injectable anti-inflammatory and antibacterial adhesive hydrogel of the present invention for in vivo application, hearts of chicken, livers of chicken, stomachs of pigs and large intestines of pigs, each having a length of 20mm, a width of 10mm and a thickness of 2mm, were prepared. In the air, the area is 10X 10mm²The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel is used for overlapping two internal organs, after the two internal organs are pressed for 1min, a shearing model is used for testing the adhesive capacity, each group of samples is repeatedly tested at least three times, the stress-strain curve is recorded, the result is shown in figure 6, figure 6 is a data graph of the adhesive bonding between the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel and different internal organs according to the embodiment of the invention, and the result shows that the internal organs are bonded to achieve effective adhesive strength.

The antibacterial performance of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel disclosed by the embodiment of the invention is evaluated by using escherichia coli (E.coli) and staphylococcus aureus (S.aureus) as pathogenic bacteria models. Mixing 0.1g of hydrogel irradiated with ultraviolet for 30min with 10 g of hydrogel⁸The antibacterial performance was evaluated by plating after co-culturing for 24 hours in CFU/mL bacterial suspension. As shown in fig. 7, fig. 7 is a graph of the antibacterial effect of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to the embodiment of the invention, and the inhibition rate of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel on escherichia coli is up to 60%, and the inhibition rate on staphylococcus aureus is up to more than 99.9%. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel disclosed by the embodiment of the invention has a good antibacterial application prospect.

The biocompatibility of the material was evaluated according to the criteria for in vitro cytotoxicity in GB/T16886. The leach liquor was prepared according to the 0.1g/mL standard. 1g of wound dressing and adhesive are extracted in 10mL of RPMI1640 medium at 37 ℃ for 24 h. Filtering with sterile filter membrane, and co-culturing with L929 fibroblast for 24h, 48h and 72 h. The Cell Count Kit-8 Kit is used for cytotoxicity analysis, and an enzyme-labeling instrument detects the light absorption value of the Kit at 450 nm. The cell experiments of blank group and experimental group are designed for detecting the experiment. As shown in FIG. 8, FIG. 8 is a graph of cytotoxicity test of gelatin-based cryogenically injected anti-inflammatory and antibacterial cohesive hydrogel leaching solution in L929 in vitro according to an embodiment of the present invention. The activity of cells treated by the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel (G-5HU-P) leaching liquor in the embodiment of the invention is more than 95%, and obvious proliferation occurs, which shows that the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel (G-5HU-P) in the embodiment of the invention has good biocompatibility and cell proliferation promoting effect.

Example 2: the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel has multiple processability

The gelatin-based low-temperature injection anti-inflammatory and antibacterial viscous hydrogel (G-5HU-P) disclosed by the embodiment of the invention has multiple processability. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel (G-5HU-P) disclosed by the embodiment of the invention is used as a wound dressing to be coated on non-woven fabric, the non-woven fabric can be stored at room temperature for a long time after the viscosity of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel is removed by airing, and the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel can be externally used after the viscosity of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel is excited by medical alcohol. Fresh gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel (G-5HU-P) can be used as a wound dressing and adhesive hydrogel preparation, is packaged in an injector or a hose, and can be taken out after refrigeration storage to be directly used for minimally invasive or noninvasive treatment of in-vivo mucosa repair without heating.

The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel (G-5HU-P) disclosed by the embodiment of the invention can also be used as a functional patch carrier and is adhered to an organ.

In order to evaluate the degradation capability of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel (G-5HU-P) of the embodiment of the invention used as a wound dressing and an adhesive in vivo, an in vitro simulated in vivo degradation test was performed. Preparing three pieces of wound dressing and adhesive, placing into 10mL DPBS buffer solution, standing in an isothermal water tank at 37 deg.C, collecting data every 24hr, recording the quality change of wound dressing, averaging, and replacing equal volume of DPBS buffer solution. The degradation results are shown in fig. 9, fig. 9 is a graph of the in vitro degradation time of the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to the embodiment of the invention, and the wound dressing and the adhesive can be degraded to 20% in 4 days. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel (G-5HU-P) disclosed by the embodiment of the invention has excellent degradation performance as a wound dressing and an adhesive, is beneficial to absorption by a human body, is green and environment-friendly, and does not need to be recycled.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel comprises gelatin, hydroxyethyl urea and punicalagin, and is characterized in that:

adding hydroxyethyl urea into gelatin water solution by adopting a one-pot mixing method, and realizing low-temperature injectability by utilizing the hydrogen bond interaction of gelatin and hydroxyethyl urea; then adding punicalagin, and forming a main network by utilizing the strong hydrogen bond interaction of the punicalagin and the gelatin to obtain the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel with the viscosity excited by medical alcohol.

2. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to claim 1, wherein the hydrogen bond interaction between gelatin and hydroxyethyl urea enables the hydroxyethyl urea and the gelatin to be tightly combined, so that the gelatin is prevented from self-forming hydrogen bonds at low temperature to self-gelatinize, and low-temperature injection is realized;

after the hydroxyethyl urea is tightly combined with the gelatin, the mass fraction of the hydrogel is 5-16%.

3. The gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to claim 2, wherein the main network is formed by the hydrogen bonding interaction of gelatin and punicalagin, the mass fraction of the gelatin is 2.5%, the mass fraction of the punicalagin is 50% -61%, and both the gelatin and the punicalagin provide adhesiveness.

4. A method for preparing the gelatin-based cold-injectable anti-inflammatory and antibacterial adhesive hydrogel according to any one of claims 1 to 3, which comprises a one-pot mixing method comprising:

taking a certain amount of gelatin aqueous solution, adding hydroxyethyl urea into the gelatin aqueous solution, uniformly mixing, adding punicalagin, and fully stirring to obtain the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel.

5. The method for preparing the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to claim 4, wherein the certain amount of gelatin aqueous solution is 0.5-1 mL of 2-15% gelatin aqueous solution.

6. The method for preparing the gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to claim 5, wherein 0.15-0.3 g of hydroxyethyl urea is added to the aqueous gelatin solution, and the hydroxyethyl urea and the gelatin are sufficiently bonded to prevent the gelatin from self-forming hydrogen bonds at a low temperature and self-gelling.

7. The method for preparing gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to claim 6, wherein the punicalagin is added in excess to fully compete with hydroxyethyl urea, so that the punicalagin and gelatin are combined to form a main network.

8. The method for preparing gelatin-based low-temperature injection anti-inflammatory and antibacterial adhesive hydrogel according to claim 7, wherein the mass of punicalagin is 0.95g to 1.2 g.