A hydrogel loaded with astragalus and notoginseng extract and its preparation method and application

Abstract

The present invention relates to a hydrogel loaded with astragalus-panax notoginseng extract and a preparation method and application thereof, belonging to the technical field of functional materials. The present invention mixes carboxymethyl chitosan / astragalus-panax notoginseng extract aqueous solution with sodium alginate / astragalus-panax notoginseng extract aqueous solution, then adds glucono-δ-lactone aqueous solution, and magnetically stirs in an ice-water bath to obtain a hydrogel loaded with astragalus-panax notoginseng extract. The hydrogel loaded with astragalus-panax notoginseng extract provided by the present invention has good rheological properties, excellent stability, suitable mechanical properties, excellent biocompatibility and rapid drug release ability, which is beneficial to wound healing. The present invention solves the problems that the astragalus-panax notoginseng extract is easily lost and the drug efficacy is short when it is directly applied to the wound, and the dispersion and release properties of the powder directly embedded in the hydrogel are poor.

Description

Technical Field

[0001] The invention relates to a hydrogel loaded with astragalus-panax notoginseng extract and a preparation method and application thereof, belonging to the technical field of functional materials. Background Art

[0002] Skin damage caused by physical and chemical reasons often occurs in life. Prolonged wound healing cycle or non-healing, scar hyperplasia, etc. bring heavy psychological pressure and economic burden to patients. Hydrogel is a cross-linked polymer with a three-dimensional network structure developed based on the "wet wound healing theory". As an important medical material, hydrogel skin dressing has the advantages of good moisture retention, drug delivery performance and biocompatibility, which can effectively shorten the wound healing process.

[0003] Both carboxymethyl chitosan and sodium alginate are natural polysaccharides with good biocompatibility and are not likely to cause immune responses in the body. Carboxymethyl chitosan and sodium alginate form a network interpenetrating structure through electrostatic interaction, and the network space of the network interpenetrating structure can be used for material encapsulation. Carboxymethyl chitosan-sodium alginate hydrogel has become a common drug carrier for wound healing due to its excellent biocompatibility, drug delivery performance and good physical and chemical properties.

[0004] In the treatment of skin injuries, Astragalus and Panax notoginseng are commonly used traditional Chinese medicines, which have the effects of diuresis, swelling, anti-inflammatory, analgesic and ulcer-regenerating tissue. In wound treatment, they show the effects of improving local microcirculation, reducing inflammatory reactions, promoting granulation tissue formation and wound healing. However, the direct application of Astragalus-Panax notoginseng extracts on the wound surface has limitations such as easy loss and short drug efficacy. The application of hydrogel carriers can help drugs to be continuously released during the wound healing process, exerting a longer-lasting therapeutic effect to achieve the effect of accelerating wound healing. The prior art directly embeds Astragalus-Panax notoginseng powder in hydrogels, which will result in poor dispersibility and release of drugs. Although the aqueous solution of Chinese medicine extracts can improve the dispersibility and release ability of drugs in hydrogel carriers, if the concentration is too high, the complex components therein will destroy the electrostatic interaction between carboxymethyl chitosan and sodium alginate, affecting the formation of hydrogels. Currently, there is an urgent need to develop a drug-loaded hydrogel that is simple in process and easy to use, integrating the unique advantages of Astragalus-Panax notoginseng extract and hydrogel, avoiding the adverse consequences caused by drugs affecting the structural stability of the hydrogel, prolonging the action time of Astragalus-Panax notoginseng extract (AP), and better promoting the healing of skin wounds. Summary of the invention

[0005] In view of the problems that the Astragalus-Panax notoginseng extract is easily lost and the efficacy is short-lived when directly applied to wounds, and the problems that the powder is directly embedded in hydrogels have poor dispersibility and release, the present invention provides a method for preparing a hydrogel loaded with Astragalus-Panax notoginseng extract and its application.

[0006] A method for preparing a hydrogel loaded with an astragalus-notoginseng extract comprises mixing a carboxymethyl chitosan / astragalus-notoginseng extract aqueous solution with a sodium alginate / astragalus-notoginseng extract aqueous solution to obtain a carboxymethyl chitosan-sodium alginate / astragalus-notoginseng extract mixed solution, then adding a glucono-δ-lactone aqueous solution, and magnetically stirring the mixture in an ice-water bath to obtain an astragalus-notoginseng extract loaded hydrogel (APCS).

[0007] In the above technical solution, the mass volume concentration of the astragalus-panax notoginseng extract in the astragalus-panax notoginseng extract aqueous solution is 12.5% ​​to 37.5%.

[0008] Preferably, the mass volume concentration of the astragalus-panax notoginseng extract in the astragalus-panax notoginseng extract aqueous solution is 12.5%.

[0009] In the above technical scheme, the preparation method of the aqueous solution of astragalus-panax notoginseng extract is: reflux extraction of astragalus and panax notoginseng slices with 75% ethanol solution to obtain an extract and remaining medicinal residues, repeat the extraction three times, and the extraction time is 2h, 2h and 1h respectively, the extract is reduced pressure concentrated and dried to obtain the astragalus-panax notoginseng extract, dissolved in water, filtered, and obtained the astragalus-panax notoginseng extract aqueous solution.

[0010] Furthermore, the mass ratio of the astragalus and Panax notoginseng slices is 1:1.

[0011] Furthermore, the mass volume ratio of the astragalus root to the Panax notoginseng slices and the 75% ethanol solution is 1:6.

[0012] In the above technical scheme, the carboxymethyl chitosan / astragalus-notoginseng extract aqueous solution is obtained by dissolving carboxymethyl chitosan in the astragalus-notoginseng extract aqueous solution.

[0013] Furthermore, the mass volume ratio of the carboxymethyl chitosan to the aqueous solution of the astragalus-panax notoginseng extract is 1:50.

[0014] In the above technical scheme, the sodium alginate / astragalus-notoginseng extract aqueous solution is obtained by dissolving sodium alginate in the astragalus-notoginseng extract aqueous solution.

[0015] Furthermore, the mass volume ratio of the sodium alginate in the sodium alginate / astragalus-notoginseng extract aqueous solution is 1:50.

[0016] In the above technical solution, the volume ratio of the carboxymethyl chitosan / astragalus-notoginseng extract aqueous solution to the sodium alginate / astragalus-notoginseng extract aqueous solution is 1:1.

[0017] In the above technical solution, the volume ratio of the glucono-δ-lactone aqueous solution to the carboxymethyl chitosan-sodium alginate / astragalus-panax notoginseng extract mixed solution is 1:4.

[0018] Furthermore, the preparation process of the glucono-δ-lactone aqueous solution is to dissolve glucono-δ-lactone in pre-cooled deionized water and shake for 5 seconds to quickly dissolve.

[0019] Furthermore, the mass volume ratio of the glucono-δ-lactone to deionized water is 1:50.

[0020] In the above technical solution, the magnetic stirring condition is stirring at 800-1500 rpm for 1-5 min.

[0021] Preferably, the method for preparing the hydrogel loaded with astragalus-panax notoginseng extract of the present invention comprises the following steps:

[0022] S1: Extract the astragalus and Panax notoginseng slices with 75% ethanol solution under reflux to obtain an extract and the remaining medicinal residues, repeat the extraction three times, the extraction time is 2h, 2h and 1h respectively, combine the extracts, decompress and concentrate the extracts and dry them to obtain an astragalus-panax notoginseng extract, dissolve it in distilled water, filter it, and obtain an astragalus-panax notoginseng extract aqueous solution;

[0023] S2: Dissolve carboxymethyl chitosan and sodium alginate in the aqueous solution of Astragalus-Panax notoginseng extract respectively, then mix them, add the aqueous solution of glucono-δ-lactone thereto, and stir them magnetically in an ice-water bath to obtain a hydrogel loaded with Astragalus-Panax notoginseng extract.

[0024] Another object of the present invention is to provide a hydrogel loaded with astragalus-panax notoginseng extract prepared by the above method.

[0025] Another object of the present invention is to provide the use of the hydrogel loaded with astragalus-panax notoginseng extract prepared by the above method in promoting wound healing.

[0026] Beneficial effects of the present invention: The hydrogel loaded with Astragalus-Panax notoginseng extract provided by the present invention has good rheology, excellent stability, suitable mechanical properties, excellent biocompatibility and rapid drug release ability. It can be used for wound repair to isolate the wound from the external environment and provide a moist environment, which is conducive to wound healing. The hydrogel provided by the present invention has the excellent characteristics of promoting fibroblast proliferation, migration and differentiation into myofibroblasts when promoting wound healing; and it can reduce inflammatory response, promote the formation of blood vessels, granulation tissue and collagen fibers, and accelerate the re-epithelialization of the wound site; in addition, the hydrogel provided by the present invention also has the effect of reducing oxidative stress, increasing angiogenesis, and promoting nerve regeneration during wound healing. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The graph shows the test results of the rheological properties, compression properties and drug release properties of the hydrogel loaded with astragalus-panax notoginseng extract and the carboxymethyl chitosan-sodium alginate hydrogel obtained in Example 1.

[0028] Figure 2 These are SEM images of the hydrogel loaded with astragalus-panax notoginseng extract and the carboxymethyl chitosan-sodium alginate hydrogel obtained in Example 1.

[0029] Figure 3 This is a graph showing the effect of the astragalus-notoginseng extract-loaded hydrogel obtained in Example 1 on the proliferation of L929 mouse fibroblasts in vitro.

[0030] Figure 4 This is a graph showing the effect of the astragalus-notoginseng extract-loaded hydrogel obtained in Example 1 on the migration of L929 mouse fibroblasts in vitro.

[0031] Figure 5 This is a graph showing the effect of the hydrogel loaded with Astragalus-Panax notoginseng extract obtained in Example 1 on the differentiation of L929 mouse fibroblasts in vitro.

[0032] Figure 6 This is a graph showing the effect of the hydrogel loaded with Astragalus and Panax notoginseng extract obtained in Example 1 on wound healing in rats at days 0, 4, 7, 10 and 14 in vivo.

[0033] Figure 7 This is a graph showing the effect of the hydrogel loaded with Astragalus and Panax notoginseng extract obtained in Example 1 on HE staining of wound tissue on the 7th and 14th days in an in vivo environment.

[0034] Figure 8 Graph showing the effect of the astragalus-notoginseng extract-loaded hydrogel obtained in Example 1 on Masson staining of wound tissue on the 7th and 14th days in an in vivo environment.

[0035] Fig. 9 This is a graph showing the effect of the hydrogel loaded with Astragalus-Panax notoginseng extract obtained in Example 1 on the immunohistochemical staining of wound tissue on the 14th day in an in vivo environment.

[0036] Fig.10 This is a graph showing the effect of the hydrogel loaded with Astragalus-Panax notoginseng extract obtained in Example 1 on the expression of Catalase, VEGF and PGP9.5 in the wound group on the 14th day in an in vivo environment. DETAILED DESCRIPTION

[0037] The following non-limiting embodiments may enable a person skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.

[0038] The test methods described in the following examples are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0039] Example 1

[0040] A method for preparing a hydrogel loaded with astragalus and notoginseng extracts, comprising the following steps:

[0041] (1) 50 g of Astragalus membranaceus slices and 50 g of Panax notoginseng slices were extracted with 75% ethanol solution under reflux for 2 h, 2 h and 1 h, respectively, to obtain 600 mL of extract and 100 g of remaining medicinal residues, the extracts were combined, the extracted Chinese medicine liquid was concentrated under reduced pressure and dried, and the Astragalus membranaceus-Panax notoginseng extract was obtained;

[0042] (2) dissolving 500 mg of the astragalus-panax notoginseng extract obtained above in 4 mL of distilled water, and filtering the mixture with a 0.45 μm filter to obtain an astragalus-panax notoginseng extract aqueous solution;

[0043] (3) Dissolve 40 mg of carboxymethyl chitosan in 2 mL of the aqueous solution of the astragalus-panax notoginseng extract obtained above to obtain a carboxymethyl chitosan / astragalus-panax notoginseng extract solution; dissolve 40 mg of sodium alginate in 2 mL of the aqueous solution of the astragalus-panax notoginseng extract obtained above to obtain a sodium alginate / astragalus-panax notoginseng extract solution; precool 1 mL of deionized water in an ice water bath, weigh 20 mg of glucono-δ-lactone and dissolve it in 1 mL of precooled deionized water, and shake for 5 seconds to quickly dissolve it to obtain a glucono-δ-lactone aqueous solution;

[0044] (4) Take 2 mL of carboxymethyl chitosan / astragalus-notoginseng extract solution and 2 mL of sodium alginate / astragalus-notoginseng extract solution and mix them to obtain a carboxymethyl chitosan-sodium alginate / astragalus-notoginseng extract solution. Then add 1 mL of the above-obtained glucono-δ-lactone aqueous solution and stir magnetically in an ice-water bath at 1000 rpm for 3 min to obtain a hydrogel loaded with astragalus-notoginseng extract.

[0045] Performance test of the hydrogel loaded with Astragalus membranaceus and Panax notoginseng extract (APCS) obtained in Example 1:

[0046] Preparation method of carboxymethyl chitosan-sodium alginate hydrogel (CS): 40 mg carboxymethyl chitosan (CMCS) and 40 mg sodium alginate (SA) were dissolved in 2 mL deionized water respectively; 2 mL CMCS solution and 2 mL SA solution were mixed and stirred to obtain a uniform suspension; 20 mg glucono-δ-lactone (GDL) was weighed and dissolved in 1 mL pre-cooled deionized water, shaken for 5 seconds to quickly dissolve, and 1 mL GDL solution was quickly added to the carboxymethyl chitosan-sodium alginate mixed solution, and magnetically stirred at 1000 rpm in an ice water bath for 1 minute to finally obtain carboxymethyl chitosan-sodium alginate hydrogel (CS).

[0047] (1) Rheological analysis of APCS hydrogel

[0048] The APCS hydrogel and CS hydrogel obtained in Example 1 were prepared into thin sheets with a diameter of 25 mm and a thickness of 2 mm. The storage modulus (G') and loss modulus (G") of the hydrogels under constant strain at 37°C were measured using a rheometer in the frequency range of 0.1 to 10 Hz, and the hydrogels were subjected to a strain scan of 0.1 to 10% at a frequency of 1 Hz. The experimental results are shown in Figure 2. Figure 1 As shown in (A, B), it can be seen that carboxymethyl chitosan-sodium alginate hydrogel (CS) loaded with AP extract can improve the elastic free energy, and compared with pure CS hydrogel, APCS hydrogel has a similar linear viscoelastic range.

[0049] (2) Compression performance test of APCS hydrogel

[0050] The APCS hydrogel and CS hydrogel obtained in Example 1 were prepared into hydrogel samples with a diameter of 5 mm and a height of 8 mm and placed between pressure plates equipped with a 100N load cell. The compressive stress-strain behavior diagram of the sample was drawn and the compressive strength and modulus of the sample were calculated based on the diagram. The experimental results are shown in Figure 1 As shown in (C), it can be seen that the addition of AP extract significantly enhanced the compressive strength of CS hydrogel.

[0051] (3) Study on the in vitro release ability of APCS hydrogel

[0052] Triterpenoid saponins are important components of Astragalus and Panax notoginseng. Therefore, by determining the content of total saponins, the release of Astragalus and Panax notoginseng in APCS can be investigated. Among them, oleanolic acid is a commonly used standard for the determination of total saponins by ultraviolet spectrophotometry and can be used to determine the content of AP extracts.

[0053] The dialysis bag containing 2 mL of APCS hydrogel and CS hydrogel was placed in 50 mL of PBS buffer solution and stirred continuously at 37 °C using a magnetic stirrer. 1 mL of PBS buffer solution was taken out at 0 h, 6 h, 12 h, 18 h, 24 h, 30 h, 36 h, 42 h, and 48 h, and the same volume of PBS buffer solution was added at the same temperature. The taken out release medium was filtered through a 0.45 μm microporous filter membrane, and the absorbance of oleanolic acid at a wavelength of 523 nm was measured using an ultraviolet spectrophotometer. All experiments were repeated 3 times, and the cumulative release of the drug was calculated. The experimental results are shown in Figure 1 As shown in (D), it can be seen that after 12 hours of sustained release, the cumulative drug release rate exceeds 90%, indicating that the APCS hydrogel can quickly release drugs under simulated wound conditions; after 24 hours, the drug release rate reaches equilibrium, indicating that the hydrogel has good controlled release behavior for drugs.

[0054] (4) Scanning electron microscopy observation of APCS hydrogel

[0055] The APCS hydrogel and CS hydrogel obtained in Example 1 were sprayed with gold, and then the pore morphology of CS and APCS hydrogels was observed using a scanning electron microscope (SEM). Figure 2 As shown, it can be seen that a larger porosity structure was observed in the CS hydrogel, while the APCS hydrogel showed a smaller porosity structure, which is due to the cross-linking of AP and CS.

[0056] (5) In vitro cell biocompatibility study of APCS hydrogel

[0057] L929 mouse fibroblasts (L929 cells, Cell Bank of the Chinese Academy of Sciences) were grown in MEM complete medium (containing 10% fetal bovine serum and 1% penicillin-streptomycin) in an environment with 5% carbon dioxide and appropriate humidity at 37°C. When the cell growth state was stable, cells in the logarithmic growth phase were used for subsequent experiments. L929 cells were added to a 96-well plate at a density of 5000 cells / well. After 24 hours of culture, the supernatant was replaced with APCS hydrogel and CS hydrogel extracts of different concentrations (0.0125%, 0.025%, 0.05%, 0.075%, 0.15% and 0.3% v / v) or AP solutions of different concentrations (12.5, 25, 50, 75, 150 and 300 mg / L). Three parallel samples were added to each group (100 μL of culture solution was added to each well). After 48 hours, 10 μL of CCK-8 reagent was added to the wells and incubated for 1.5 hours. The absorbance at 450 nm of each well was measured by a microplate reader. At all concentrations, the cell survival rate exceeded 95%, and no cytotoxicity was observed in the APCS group at the highest concentration.

[0058] Application of the hydrogel loaded with astragalus and notoginseng extract obtained in Example 1 in promoting wound healing:

[0059] (1) Cell experiments

[0060] Cell proliferation experiment: L929 mouse fibroblasts were used as the research object to evaluate the effect of APCS hydrogel on cell proliferation. L929 mouse fibroblasts were inoculated into 96-well plates at 1000 cells / well and cultured for 24 hours. The supernatant was replaced with APCS hydrogel and CS hydrogel extract (0.075% v / v) or AP solution (75 mg / L). After culturing for 24 hours, 48 ​​hours, and 72 hours, 10 μL of CCK-8 reagent was added to the wells and incubated for 1.5 hours. The absorbance at 450 nm of each well was measured with an enzyme-labeled instrument. The experimental results are shown in Figure 2. Figure 3 As shown, it can be seen that CS hydrogel and AP solution have different degrees of promoting effects on the proliferation of fibroblasts, and the APCS hydrogel group has a particularly prominent promoting effect on the proliferation of L929 cells (P < 0.05).

[0061] Cell scratch test: L929 mouse fibroblasts were used as the research object to evaluate the effect of drugs on cell migration. L929 mouse fibroblasts were cultured at 2.5×10 5 Cells were inoculated into 6-well plates at 100% fusion, and a straight line was vertically drawn using a 200 μL sterile pipette tip. The cells were washed with PBS to remove cell debris and then starved for 5 h in serum-free medium. The supernatant was replaced with APCS hydrogel and CS hydrogel extract (0.075% v / v) or AP solution (75 mg / L). Cell migration was recorded at 0 h, 12 h, and 24 h, and the scratch area was photographed at ×40 magnification using an inverted microscope and measured using Image J software. The experimental results are shown in Figure 2. Figure 4 As shown, it can be seen that the application of the hydrogel carrier helps the AP extract to better promote the migration of fibroblasts (P < 0.05).

[0062] In vitro differentiation experiment of fibroblasts into myofibroblasts: 5×10 5 The cells were inoculated at a density of 100 μg / well in a 6-well plate. After 24 h, the supernatant was replaced with APCS hydrogel and CS hydrogel extract (0.075% v / v) or AP solution (75 mg / L) for 24 h. The α-SMA content in the cells was detected by Western blotting. Figure 5 As shown, it can be seen that AP extract and APCS hydrogel treatment can effectively promote fibroblast differentiation in vitro (P < 0.05).

[0063] (2) Construction of rat full-thickness skin defect model and wound healing experiment

[0064] Thirty-two SD rats (180-220 g) were fasted for 12 h after one week of adaptive feeding. The rats were anesthetized by intraperitoneal injection of 10% chloral hydrate, the hair on the back was shaved, and a circular wound with a diameter of 2 cm was made with scissors. The rats were housed in individual cages and randomly divided into 4 groups (n=8): the NC group received no treatment, the CS group was treated with 0.1 mL CS, the AP group was treated with 0.1 mL AP, and the APCS group was treated with 0.1 mL APCS.

[0065] In order to study the therapeutic effect of APCS hydrogel on experimental animals in vivo, full-thickness wounds were created on the backs of rats and treated with CS hydrogel, AP solution and APCS hydrogel respectively. Photos of the wounds of each group were taken at 0d, 4d, 7d, 10d and 14d. Figure 6 As shown in the figure, it can be seen that: during the entire treatment period, there was no significant difference in the wound size between the CS group and the NC group. After 10 days of treatment, the wounds of the rats in the AP group had obvious healing compared with the NC group. During the entire process of wound treatment, the APCS group showed a good effect in promoting wound healing (P < 0.05), which shows that the application of CS hydrogel carrier helps AP to better exert its efficacy in wound repair, and APCS hydrogel has a significant promoting effect on wound healing (P < 0.05).

[0066] HE staining of full-thickness skin wound tissue: On the 7th and 14th days after rat modeling, 4 rats were randomly killed in each group, and normal tissues from the wound site and nearby areas were taken. The skin tissues for pathological sections were dehydrated, embedded, cut into 5 μm thick sections, and stained with hematoxylin and eosin (H&E). Figure 7 As shown, it can be seen that both AP solution and APCS hydrogel can promote angiogenesis, and APCS hydrogel treatment can shorten the transition time from the inflammatory phase to the proliferation phase, promote granulation tissue regeneration and wound re-epithelialization, thereby accelerating wound healing.

[0067] Masson staining in full-thickness skin wound tissue: To evaluate the collagen production content, tissue sections were stained with a Masson staining kit and the collagen content of the wound surface was detected using Image J software. Figure 8 As shown, it can be seen that APCS hydrogel treatment promoted the synthesis of collagen during wound healing.

[0068] Immunohistochemical detection of CD31 and α-SMA levels: To evaluate the effect of the drug on wound angiogenesis, immunohistochemical staining with CD31 and α-SMA was performed. According to the kit instructions, each tissue section was incubated in 3% H2O2 for 10 minutes, incubated with CD31 or VEGF primary antibody at 4°C overnight, and then incubated with secondary antibody at 37°C for 30 minutes. The experimental results are shown in Figure 2. Fig. 9 As shown, it can be seen that APCS hydrogel can promote the regeneration of new blood vessels and mature blood vessels during wound repair.

[0069] Western blotting analysis was used to detect the levels of Catalase, VEGF, and PGP9.5: Rat wound tissue was used to verify the mechanism by which APCS affects wound healing. In order to extract total protein from the tissue, RIPA buffer was used. The concentration was determined using a BCA protein quantification kit. SDS polyacrylamide gel electrophoresis and protein transfer were performed at a voltage of 80 V. The polyvinylidene fluoride (PVDF) membrane was blocked in skim milk at 37°C for 1 h, then incubated with a primary antibody (including Catalase, VEGF, PGP9.5) at 4°C overnight, and then the PVDF membrane was incubated with a secondary antibody at room temperature for 1 h. Each protein was repeated three times. The experimental results are shown in the following figure. Fig.10 As shown, it can be seen that APCS hydrogel inhibits oxidative stress and promotes blood vessel and nerve regeneration during the proliferation stage of wound healing (P < 0.05).

[0070] The astragalus-panax notoginseng loaded hydrogel (APCS) prepared by the present invention has good stability, biocompatibility and rapid drug release performance, and can promote the healing of full-thickness wound defects in rats. On the L929 cell line, APCS hydrogel can significantly promote the proliferation and migration of fibroblasts and the differentiation of fibroblasts into myofibroblasts; in the full-thickness skin defect wounds of SD rats, APCS hydrogel can reduce the inflammatory response of tissues, promote granulation tissue regeneration and collagen deposition, improve re-epithelialization, and inhibit oxidative stress and promote blood vessel and nerve regeneration in the proliferation stage of wound healing. APCS hydrogel is of great value to wound healing in rats and may be a potential therapy for the treatment of full-thickness skin defects.

Claims

1. A method for preparing a hydrogel loaded with astragalus and notoginseng extract, characterized in that: The carboxymethyl chitosan / astragalus-notoginseng extract aqueous solution and the sodium alginate / astragalus-notoginseng extract aqueous solution were mixed to obtain a carboxymethyl chitosan-sodium alginate / astragalus-notoginseng extract mixed solution, and then a glucono-δ-lactone aqueous solution was added and magnetically stirred in an ice-water bath to obtain a hydrogel loaded with astragalus-notoginseng extract.

2. The preparation method according to claim 1, characterized in that: The mass volume concentration of the astragalus-panax notoginseng extract in the astragalus-panax notoginseng extract aqueous solution is 12.5% ​​to 37.5%.

3. The preparation method according to claim 1, characterized in that: The preparation method of the astragalus-panax notoginseng extract aqueous solution is as follows: reflux extraction of astragalus and panax notoginseng slices with 75% ethanol solution to obtain an extract and remaining medicinal residues, repeating the extraction three times, with extraction times of 2h, 2h and 1h respectively, decompressing and concentrating the extract, drying to obtain the astragalus-panax notoginseng extract, dissolving it in water, filtering, and obtaining the astragalus-panax notoginseng extract aqueous solution.

4. The preparation method according to claim 1 or 3, characterized in that: The mass ratio of the astragalus and Panax notoginseng slices is 1:1; the mass volume ratio of the astragalus, Panax notoginseng slices and 75% ethanol solution is 1:

6.

5. The preparation method according to claim 1, characterized in that: The mass volume ratio of carboxymethyl chitosan to the astragalus-notoginseng extract aqueous solution in the carboxymethyl chitosan / astragalus-notoginseng extract aqueous solution is 1:50; the mass volume ratio of sodium alginate to the astragalus-notoginseng extract aqueous solution in the sodium alginate / astragalus-notoginseng extract aqueous solution is 1:

50.

6. The preparation method according to claim 1, characterized in that: The volume ratio of the carboxymethyl chitosan / astragalus-notoginseng extract aqueous solution to the sodium alginate / astragalus-notoginseng extract aqueous solution is 1:

1.

7. The preparation method according to claim 1, characterized in that: The volume ratio of the glucono-δ-lactone aqueous solution to the carboxymethyl chitosan-sodium alginate / astragalus-notoginseng extract mixed solution is 1:4, wherein the mass volume ratio of the glucono-δ-lactone to deionized water is 1:

50.

8. The method according to claim 1, characterized in that: The magnetic stirring condition is stirring at 800-1500 rpm for 1-5 min.

9. The hydrogel loaded with Astragalus membranaceus-Panax notoginseng extract prepared by the method according to any one of claims 1 to 8.

10. Use of the hydrogel loaded with astragalus and notoginseng extracts as claimed in claim 9 in promoting wound healing.

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