Radix pseudostellariae polysaccharide composite hydrogel, preparation method and application thereof

Abstract

The present application provides a kind of radix pseudoginseng polysaccharide composite hydrogel and its preparation method and application, the composite hydrogel includes hydrogel main body, active ingredient loaded in hydrogel main body and functional coating, the hydrogel main body is prepared by OPH with AP according to 1:1-2 Volume ratio is mixed, the active ingredient is PTA and MnCoO@PLE, the functional coating is rGO@PDA, PTA, MnCoO@PLE and rGO@PDA are loaded in hydrogel main body with equal volume ratio, take PTA and MnCoO@PLE into OPH solution, then add AP solution and rGO@PDA to prepare, have the multifunctional characteristics of on-demand oxygen supply, hemostasis and anti-inflammatory, and promote cell proliferation and migration generation, can be used as a new type of medical multifunctional material in diabetic wound treatment, has good application prospect in medical material field and clinic.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of traditional Chinese medicine, in particular to a Pseudostellaria heterophylla polysaccharide composite hydrogel, a preparation method thereof and application. BACKGROUND

[0002] Compared with common wounds, diabetic chronic wounds have the characteristics of complex pathogenesis, high infection probability, long recovery time and high recurrence rate, which seriously affect the quality of life of patients and increase the burden of the social medical care system. Recently, more and more evidence shows that excessive oxidative stress plays a crucial role in the pathology of impaired wound healing in diabetes. Under this adverse wound microenvironment, uncontrolled accumulation of reactive oxygen species (ROS) can induce oxidative stress and inhibit the viability of wounds. Endogenous keratinocytes, fibroblasts, vascular endothelial cells, stem cells and growth factors in the injured tissue are inactivated, thereby greatly impairing their regenerative potential. Oxygen is essential for the aerobic metabolism and normal function of cells, and hypoxia is also a key problem limiting tissue repair.

[0003] Lumen stenosis and microcirculation disorders caused by diabetic microangiopathy lead to the formation of chronic hypoxia around the wound, and the recruitment of high-oxygen-consuming inflammatory cells also exacerbates this hypoxic state. The pathological microenvironment of diabetic wounds is the result of the simultaneous action of ROS accumulation and chronic hypoxia. Therefore, biomaterials with both ROS scavenging and oxygen-producing functions represent a new trend in regenerative medicine to accelerate diabetic wound healing and regeneration.

[0004] At present, several advanced materials are considered to be the best candidate materials for wound healing, such as gauze, fibrous membrane and hydrogel. Among them, "hydrogel" is a polymer material that can absorb and retain water in its three-dimensional (3D) network. Hydrogel has a high water content, porosity and flexibility, which is very similar to natural biological tissues, and exceeds other synthetic biomaterials. Hydrogels are mostly prepared using a single or multiple types of natural polymers, and polysaccharides have rich properties, good biocompatibility, biodegradability, non-toxic degradation products, easy to be metabolized and cleared by the human body, and even can be absorbed and utilized as nutrients. The polysaccharide-based hydrogel effectively absorbs wound exudates, reduces chronic infection, and provides conditions for rapid healing. Therefore, hydrogels made of polysaccharides have been widely used as substitutes for renewable materials.

[0005] Unlike traditional hydrogels, smart hydrogels can easily facilitate targeted drug release within specific injury areas, leading many researchers to explore their utility as drug controlled release media. Most existing hydrogels exhibit a single stimulus-responsive ability. However, the inflammatory microenvironment is associated with increased ROS production and decreased pH, which can be a result of metabolic changes. Therefore, both ROS levels and pH values are appropriate stimuli for triggering hydrogel-mediated drug release in an inflammatory environment. Given these features, it is necessary to design a smart-based stimulus-responsive hydrogel with ideal dynamic self-healing properties, capable of sequentially delivering antioxidant and oxygen-generating drugs as a means to mediate the diabetic wound healing process. SUMMARY

[0006] The technical problem to be solved by the present application is to provide a P. notoginseng polysaccharide composite hydrogel.

[0007] Another technical problem to be solved by the present application is to provide a preparation method of the P. notoginseng polysaccharide composite hydrogel.

[0008] Another technical problem to be solved by the present application is to provide an application of the P. notoginseng polysaccharide composite hydrogel.

[0009] The technical solution adopted by the present application is:

[0010] A P. notoginseng polysaccharide composite hydrogel, comprising a hydrogel main body, active ingredients loaded in the hydrogel main body, and a functional coating, wherein the hydrogel main body is prepared by mixing OPH (oxidized P. notoginseng polysaccharide) and AP (amidated pectin polysaccharide) at a volume ratio of 1:1-2, the active ingredients are PTA (polymerized tannic acid product polytannic acid) and MnCoO@PLE (a peroxidase-like nanoscale enzyme, a mesoporous manganese cobalt oxide), and the functional coating is rGO@PDA (polydopamine modified graphene oxide).

[0011] Preferably, in the P. notoginseng polysaccharide composite hydrogel, the volume ratio of PTA, MnCoO@PLE, rGO@PDA, and OPH is 0.75-2.75:0.75-2.75:0.75-2.75:3.75-10.

[0012] Preferably, in the P. notoginseng polysaccharide composite hydrogel, the volume ratio of PTA, MnCoO@PLE, rGO@PDA, and OPH is 1:1:1:5.

[0013] Preferably, the above-mentioned P. notoginseng polysaccharide composite hydrogel has a mass ratio of OPH to AP of 1:2, and has better thermal stability, antioxidant performance, rheological property and swelling property.

[0014] Preferably, the above-mentioned P. notoginseng polysaccharide composite hydrogel has a concentration of rGO@PDA of 3 mg / mL, and has better antioxidant performance, rheological property and biocompatibility.

[0015] Preferably, the above-mentioned P. notoginseng polysaccharide composite hydrogel is prepared by the following method: PTA and MnCoO@PLE are added to an OPH solution, and then an AP solution and rGO@PDA are added, to obtain the P. notoginseng polysaccharide composite hydrogel.

[0016] The preparation method of the above-mentioned P. notoginseng polysaccharide composite hydrogel comprises the following specific steps:

[0017] (1) Preparation of OPH: P. notoginseng polysaccharide is oxidized by a sodium periodate oxidation method to prepare oxidized P. notoginseng polysaccharide;

[0018] (2) Preparation of AP: pectin is dispersed in a mixture of ammonia and pre-cooled isopropanol solution and stirred vigorously; after filtration, the pectin is re-suspended in acidic isopropanol by magnetic stirring, stirring, and then the product is washed with isopropanol and dried after filtration;

[0019] (3) Preparation of PTA: tannic acid is dissolved in deionized water; the pH of the solution is adjusted with potassium hydroxide; after continuous stirring, centrifugation and freeze-drying, the product is stored;

[0020] (4) Preparation of MnCoO@PLE: manganese acetate tetrahydrate and polyvinylpyrrolidone are added to a mixture of ethanol and water, and potassium hexacyanocobaltate(III) is added with vigorous stirring; the reaction solution is kept overnight, and after centrifugation and drying, the freeze-dried material is dissolved in ethanol to obtain solution A; ammonia is dissolved in ethanol and stirred vigorously to obtain solution B; solution B is added to solution A, and then ethyl silicate is added, and after stirring, the freeze-dried material is obtained by centrifugation; the freeze-dried material is heated for 4 hours, and then etched with NaOH aqueous solution; after centrifugation and freeze-drying, a purified black powder is obtained; the purified black powder is mixed with a solution of ε-polylysine, and then ultrasonically treated; the product is purified by washing / centrifugation cycles and dried to obtain MnCoO@PLE;

[0021] (5) Preparation of rGO@PDA: graphene and dopamine hydrochloride are dissolved in Tris-HCl buffer, and ultrasonically treated for 30 minutes; the mixture is stirred vigorously at room temperature for 24 hours; after centrifugation, the product is washed with water and ethanol several times, and finally freeze-dried to obtain rGO@PDA;

[0022] (6) Preparation of hydrogel: PTA and MnCoO@PLE were added to OPH solution, and then AP and rGO@PDA solution were added to obtain a composite hydrogel.

[0023] Preferably, the preparation method of the P. notoginseng polysaccharide composite hydrogel, the step (1) is to dissolve P. notoginseng polysaccharide in deionized water, sodium periodate is added to the solution and reacted at room temperature in the dark, then ethylene glycol is added to the mixed solution to terminate the oxidation; the product is dialyzed and freeze-dried to obtain OPH.

[0024] Preferably, the preparation method of the P. notoginseng polysaccharide composite hydrogel, the specific steps are as follows:

[0025] (1) Dissolve P. notoginseng polysaccharide in deionized water, after completely dissolved, add sodium periodate to the solution and stir at room temperature in the dark; after 24h reaction, add ethylene glycol to the mixed solution to terminate the further oxidation of polysaccharide; the obtained product is packed into dialysis bag and dialyzed, the deionized water is changed 3 times a day; after dialysis for 3 days, the solution is freeze-dried to obtain product OPH; wherein the mass ratio of P. notoginseng polysaccharide to sodium periodate is 1:1.5, and the reaction is carried out in a stirrer at 40℃ in the dark for 10 hours;

[0026] (2) Disperse pectin in a mixture based on ammonia and pre-cooled isopropanol solution by vigorous stirring for 24 hours, the volume ratio of ammonia and pre-cooled isopropanol solution is 2:3; filter, resuspend AP in acidic isopropanol by magnetic stirring, the pH of the acidic isopropanol is 4.5, stir for 10 min and then filter; wash the obtained product with 70% isopropanol until the product is free of chlorine; dry the obtained product;

[0027] (3) Dissolve tannic acid in deionized water and adjust the solution pH to 11; after continuous stirring at room temperature for 16h, centrifuge the obtained precipitate (PTA nanorods) and wash with DW, freeze-dry and store;

[0028] (4) Dissolve 38.7g of manganese acetate tetrahydrate and 13.3g of polyvinylpyrrolidone in 40mL of anhydrous ethanol and 15mL of H2O; dissolve 27.5g of potassium hexacyanocobalt(III) in 20mL of H2O. In H2O, ammonia was added dropwise to the above mixed solution of manganese acetate tetrahydrate and polyvinylpyrrolidone under vigorous stirring; the reaction solution was kept at room temperature overnight; after centrifugation, the product was washed with deionized water and ethanol and dried; the dried product was dissolved in ethanol and sonicated for 30 minutes to obtain solution A; then, ammonia was added to an equal volume of ethanol and stirred vigorously for 30 minutes to obtain solution B; solution B was added to solution A, and then ethyl silicate was added dropwise using a 1000 mL pipette; the mixture was stirred for 3 hours and overnight, then centrifuged, and the product was washed with deionized water and ethanol, and finally dried; the dried product was heated at 500 °C for 4 hours, and then etched with NaOH aqueous solution; the solution was centrifuged, washed and dried to obtain purified black powder, i.e., MnCoO nanoparticles; 10 mg / mL ∈-polylysine solution and 1 mg / mL MnCoO aqueous solution were mixed together at a ratio of 5:1 and sonicated for 20 minutes; the product was purified by washing / centrifugation cycle with deionized water and then freeze-dried to obtain MnCoO@PLE;

[0029] (5) Graphene and dopamine hydrochloride were dissolved in Tris-HCl buffer (pH=8.5) at a mass ratio of 1:1 and sonicated for 30 minutes; the mixture was stirred vigorously at room temperature for 24 hours; the resulting mixture was purified and filtered, and further washed with water and ethanol to obtain rGO@PDA, which was then lyophilized to obtain a black powder.

[0030] (6) PTA and MnCoO@PLE were added to OPH solution, and then AP solution and rGO@PDA were added to obtain composite hydrogel.

[0031] Preferably, in the above-mentioned method for preparing Codonopsis pilosula polysaccharide composite hydrogel, the concentration of rGO@PDA in step (6) is 1-3 mg / mL (preferably 3 mg / mL), and the concentrations of PTA and MnCoO@PLE are 1 mg / mL.

[0032] The above-mentioned Codonopsis pilosula polysaccharide composite hydrogel is used in the preparation of reagents or drugs for scavenging reactive oxygen species that generate O2.

[0033] The above-mentioned Codonopsis pilosula polysaccharide composite hydrogel is used in the preparation of drugs for improving the hypoxic microenvironment of diabetic wounds.

[0034] The above-mentioned Codonopsis pilosula polysaccharide composite hydrogel is used in the preparation of hemostatic drugs (in vivo or in vitro wound hemostasis).

[0035] Preferably, in the application of the above-mentioned Codonopsis pilosula polysaccharide composite hydrogel, the hemostatic drug is the hemostatic gel.

[0036] The application of the above-mentioned polysaccharide composite hydrogel of radix pseudostellariae in the preparation of a drug for promoting the remodeling and functional reconstruction of the collagen matrix of a diabetic wound tissue.

[0037] The beneficial effects of the present application are:

[0038] The above-mentioned polysaccharide composite hydrogel of radix pseudostellariae is prepared by dynamic acylhydrazone bonds between aldehyde groups of oxidized polysaccharide of radix pseudostellariae (OPH) and hydrazides of amidated pectin (AP), dynamic imine bonds between aldehyde groups of OPH and amines of MnCoO@PLE nanoszyme, and direct physical cross-linking of polyphenol and MnCoO@PLE nanoszyme, and the hydrogel is coated with a reduced graphene oxide (rGO@PDA) coating, and the obtained hydrogel has multiple functional properties such as on-demand oxygen supply, hemostasis and anti-inflammatory, and promotion of cell proliferation and migration generation, has activities such as hemostasis, anti-inflammatory and antioxidant, can efficiently remove ROS generated in a wound and produce oxygen, reduce the damage of ROS at a wound site and can reform severe inflammation, improve the hypoxic microenvironment, reduce the inflammatory response in a diabetic wound, promote the repair of a diabetic wound, the hydrogel has good self-healing and injectability, is beneficial to drug administration at a wound site, can be used as a new type of medical multifunctional material for diabetic wound treatment, and has a good application prospect in the field of medical materials and in clinical treatment. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 is the characterization of nanomaterials and polysaccharides; wherein (a) TEM characterization of PTA and MnCoO@PLE; (b) FT-IR characterization of OPH, (c) AP and (d) OPH-AP hydrogel.

[0040] Figure 2 is the preparation of the hydrogel; wherein (a) SEM of the blank hydrogel and the drug-loaded hydrogel; (b) injectability determination of the OPH-AP hydrogel; (c) OPH-AP@PTA@MnCoO@PLE@rGO@PDA formation picture.

[0041] Figure 3 is performance test 1 of the hydrogel; wherein (a) thermogravimetric analysis; (b), (c) and (d) rheological property determination.

[0042] Figure 4 is performance test 2 of the hydrogel; wherein (a) and (b) swelling property; (c) DPPH clearance rate of the hydrogel with different contents of rGO@PDA coating; (d) in vivo antioxidant activity of the hydrogel with different proportions of OPH-AP and different contents of rGO@PDA coating;

[0043] Figure 5Performance test 3 of the hydrogel; wherein, (a) biocompatibility of the hydrogel with different proportions of OPH-AP and different contents of rGO@PDA coating; (b) blood compatibility of the hydrogel with different proportions of OPH-AP and different contents of rGO@PDA coating.

[0044] Figure 6 Catalytic activity characterization of the catalase-like enzyme of the composite hydrogel; wherein, (a) UV-Vis absorption spectrum of the hydrogel after adding Ti(SO4)2 solution. The concentration of MnCoO@PLE nanoscale enzyme in the hydrogel is different; (b) decomposition of H2O2 (1.0 m) using and not using MnCoO@PLE nanoscale enzyme and PTA; (c) continuous H2O2 consumption catalytic ability of the hydrogel when repeatedly adding H2O2 (1.0 m); (d) generation of oxygen hydrogel with and without MnCoO@PLE nanoscale enzyme and PTA. The concentration of H2O2 is 0.1 m; (e) repeated oxygen production catalytic ability of the hydrogel when repeatedly adding H2O2 (0.1 m) (n = 3).

[0045]

[0046] Figure 7 Enhancement of skin cell survival and proliferation by the hydrogel by reducing ROS accumulation and generating oxygen; wherein, (a) ROS-specific probe (DCFH-DA) and (b) oxygen indicator Ru(dpp)3Cl2 evaluation of ROS clearance and oxygen generation after different treatments of HaCaT cells, scale: 100 μm.

[0047] Figure 8 Intracompound hydrogel hemostasis result analysis chart; wherein, (a) hydrogel hemolysis quantification picture; (b) hydrogel in vitro coagulation time; (c) hydrogel liver hemostasis amount.

[0048] Figure 9 Schematic diagram of the hydrogel promoting diabetic wound repair; wherein, (a) wound size change at 0, 3, 6, 10, 15 days; (b) wound healing area heat map of each group; (c) wound area healing quantification chart. DETAILED DESCRIPTION

[0049] In order to make the skilled in the art better understand the technical solutions of the present application, the technical solutions of the present application will be further described in detail below in combination with the drawings and specific embodiments.

[0050] For the process parameters not specifically mentioned, refer to the conventional technology. Unless otherwise specified, the reagents, methods and equipment used in the present application are conventional reagents, methods and equipment in the technical field.

[0051] Example 1

[0052] I. Test materials​

[0053] Sodium periodate (analytical pure), graphene oxide (GO) and dopamine hydrochloride were purchased from Shanghai Maikelin Biochemical Co., Ltd.; Tannic acid, potassium hexacyanocobaltate (K3[Co(CN)6]), tetraethyl orthosilicate (TEOS, ≈99%), manganese acetate [Mn(CH3COO)2·4H2O], ε-polylysine, polyvinylpyrrolidone (PVPON, K-30) were purchased from Tianjin Xinsite Reagent Co., Ltd. Triton X-100 and streptozotocin (STZ) were purchased from Beijing Solabio Technology Co., Ltd., isoflurane was purchased from Tianjin Ruipu Biotechnology Co., Ltd. Ti(SO4)2was purchased from Shanghai Maierl Biochemical Technology Co., Ltd., ethanol (C2H5OH, ≈99.7%), ethylene glycol, isopropyl alcohol and ammonia water were purchased from Tianjin Yuanli Chemical Co., Ltd. Cell culture medium, 0.25% trypsin / EDTA were purchased from Wuxi Xinning Biological Technology Co., Ltd. 2,7-dichlorofluorescein diacetate (DCFH-DA) was provided by Yixing Biosciences (Shanghai) Co., Ltd., [Ru(dpp)3Cl2] was provided by Shanghai Bibo Biological Technology Co., Ltd. Cell counting kit-8 (CCK-8) (100T) was purchased from Tianjin Yishengyuan Biological Technology Co., Ltd.

[0054] Animals: All SD male rats (180-200 g) were purchased from Beijing Sibeifu Experimental Animal Technology Co., Ltd. (Beijing, China) and were housed in a standard laboratory environment (22 ± 2℃, humidity: 60 ± 5%, 12 h light / 12 h dark cycle). All experimental procedures were approved by the Tianjin University Animal Care and Use Committee (No. 2022-11-20-1) and strictly followed the National Institutes of Health (NIH) Guide for the Care and Use of Laboratory Animals.

[0055] Cells: Human immortalized keratinocytes (Hacat) and embryonic fibroblasts (NIH / 3T3) were purchased from Wuxi Xinning Biological Technology Co., Ltd.

[0056] II. Preparation of hydrogel

[0057] (1) Preparation of OPH: 0.5 g of polysaccharide from Radix Pseudoginseng was dissolved in 20 mL of deionized water. After complete dissolution, 0.75 g of sodium periodate was added to the solution and stirred at room temperature in the dark. After 24 h of reaction, 1 g of ethylene glycol was added to the mixed solution to terminate the further oxidation of polysaccharide from Radix Pseudoginseng. The resulting product was packed into a dialysis bag and dialyzed against deionized water, which was changed three times a day. After 3 days of dialysis, the solution was freeze-dried for 3 days to obtain the product.

[0058] (2) Preparation of AP: 12 g of pectin was dispersed in a mixture of 40 mL of 17 M aqueous ammonia and 60 mL of pre-cooled isopropanol solution, and stirred vigorously for 24 hours. Then, the AP was filtered with a Buchner funnel. The AP was re-suspended in acidic isopropanol by magnetic stirring for 10 minutes, and then filtered. After that, the resulting material was washed several times with 70% isopropanol until the product was free of chlorine. Then, the product was re-washed with pure isopropanol for further purification. Finally, the resulting product was dried.

[0059] (3) Preparation of PTA: First, 0.2 g of tannic acid was dissolved in deionized water (mL). Then, the solution pH was adjusted to 11 with potassium hydroxide (2 mol / L). After continuous stirring at room temperature (25 °C) for 16 h, the resulting precipitate (PTA) was centrifuged and washed with DW three times, and lyophilized for storage.

[0060] (4) Preparation of MnCoO@PLE: 38.7 g of manganese acetate tetrahydrate and 13.3 g of polyvinylpyrrolidone were dissolved in 40 mL of ethanol and 15 mL of H2O. Then, 27.5 g of potassium hexacyanocobaltate (III) was dissolved in 20 mL of deionized water and added dropwise to the above mixture under vigorous stirring. The reaction solution was kept at room temperature overnight. After centrifugation, the product was washed with deionized water and ethanol and dried. The dried product 70 mg was dissolved in 70 mL of ethanol and ultrasonicated for 30 minutes to obtain solution A. Subsequently, 4 mL of aqueous ammonia was added to the same volume of ethanol and stirred vigorously for 30 minutes to obtain solution B. Solution B was added to solution A, and then 268 μL of ethyl silicate was added dropwise. Stirring was carried out for 3 hours and overnight, followed by centrifugation, and the product was washed with deionized water and ethanol, and finally dried. The dried product was heated at 500 °C for 4 hours, and then etched with 4 M aqueous NaOH solution. After centrifugation and drying of the solution, a purified black powder, i.e., MnCoO nanoparticles, was obtained. A 10 mg / mL solution of ε-polylysine and a 1 mg / mL aqueous solution of MnCoO were mixed together at a ratio of 5:1, and ultrasonicated for 20 minutes. Then, the product was purified by several washing / centrifugation cycles with deionized water, and freeze-dried.

[0061] (5) Preparation of rGO@PDA: 20 mg of graphene and 20 mg of dopamine hydrochloride were dissolved in 40 mL of Tris-HCl buffer (pH = 8.5) and ultrasonicated for 30 minutes. The mixture was stirred vigorously at room temperature for 24 hours. The resulting mixture was purified and filtered, and further washed several times with water and ethanol to obtain rGO@PDA, which was freeze-dried to obtain a black powder.

[0062] (6) Preparation of hydrogel:

[0063] (6.1) Preparation of blank hydrogel

[0064] Take 250 mg of OPH and AP respectively, dissolve in 10 mL of PBS, stir until completely dissolved, obtain OPH and AP stock solution; take two kinds of solution, mix two kinds of solution according to the ratio of 1:1, 1:1.5, 1:2, stir uniformly, stand to obtain hydrogel, and determine whether it is gelled by test tube inversion method.

[0065] (6.2) Preparation of rGO@PDA coating hydrogel: take 1 mL of OPH and AP solution, add 200 μL of 1 mg / mL, 2 mg / mL and 3 mg / mL rGO@PDA solution respectively.

[0066] (6.3) Preparation of PTA and MnCoO loaded hydrogel: take 200 μL of 1 mg / mL PTA and MnCoO@PLE respectively, add to 1 mL of OPH solution, then add 1 mL of AP solution and 200 μL of rGO@PDA to obtain composite hydrogel.

[0067] OPH-AP hydrogel and OPH-AP@PTA@MnCoO@PLE@rGO@PDA composite hydrogel of different proportions (OPH and AP 1:1, 1:1.5, 1:2) are prepared according to the above method, and OPH, AP, PTA, MnCoO, MnCoO@PLE and their hydrogels prepared above are characterized and tested, and the specific circumstances are as follows:

[0068] (1) Characterization of OPH, AP and OPH-AP.

[0069] The chemical structure of OPH, AP and OPH-AP is characterized by Fourier infrared spectroscopy FT-IR and scanning electron microscopy SEM.

[0070] (2) The injectability of hydrogel is verified by injecting each group of hydrogel with 1 mL syringe to verify the injectability of various hydrogels.

[0071] (3) Rheological property determination of hydrogel: frequency (FREQ) scan with 0.5% strain and 0.1 to 10 rads -1 oscillation FREQ.

[0072] (4) Self-healing property determination of hydrogel: at a fixed angular frequency (1 rad-s -1 ), the self-healing behavior is tested by alternating strain sweep test. The amplitude oscillation strain is switched from small strain (γ = 1.0%, every interval 100 seconds) to large strain (γ = 200%, every interval 100 seconds).

[0073] (5) Swelling ratio of hydrogel: The water uptake and deswelling properties of the developed pectin hydrogel were investigated using the gravimetric method. For water uptake determination, freeze-dried hydrogel (Wd) was immersed in DW at room temperature and weighed (Wt) after a set time. When the hydrogel weight no longer changed, the operation was stopped and the water uptake (WU) was defined as follows:

[0074] WU (%) = (Wt - Wd) / Wd x 100%

[0075] For deswelling determination, the pectin hydrogel in the swelling equilibrium state was placed in an oven (37 °C). The initial weight of the hydrogel was W0, while Wt was the weight after deswelling for a certain time. The water retention (WR) formula is as follows:

[0076] WR (%) = Wt / W0 x 100%

[0077] (6) DPPH radical scavenging activity

[0078] For 1,1-diphenyl-2-picrylhydrazyl (DPPH) test, hydrogel extract (5 mg / mL) was mixed with an equal volume of DPPH methanol solution (200 mM). After incubation for 30 min, the optical density value (OD) of the supernatant was measured at 517 nm, and the calculation formula was:

[0079] D = [1 - (As - A0) / Ac] x 100%

[0080] (A0: OD value of sample; Ac: OD value of DPPH; As: OD value of DPPH after sample treatment)

[0081] (7) In vivo antioxidant activity determination: To verify the ROS scavenging ability of the hydrogel, NH3T3 cells were stimulated with different concentrations of H2O2 and their survival rate was detected. NH3T3 cells (1 x 10 4 ) were cultured in 96-well plates overnight. At the same time, the hydrogel (100 mg) was added to the solution containing 100 μL H2O2. After 48 h, the solution (10 μL) after the reaction of the hydrogel with H2O2 was added to the cells. After 24 h of incubation, the cell culture medium was replaced with fresh culture medium containing 10% CCK-8, and the cells were incubated for another 30 min. Finally, cell viability was evaluated using the cell counting kit-8 (CCK-8).

[0082] (8) Cytotoxicity of hydrogel: 50 μL of sterilized hydrogel was prepared and incubated with 1 mL of DMEM for 48 h. NIH3T3 cells were seeded in a 96-well plate and incubated for 24 h. Then the culture medium was replaced with hydrogel extract and incubated for another 48 h. Cell viability was evaluated using the cell counting kit-8 (CCK-8) according to the manufacturer's instructions, with cells cultured in complete growth medium serving as a control.

[0083] (9) Hemocompatibility of hydrogels: Red blood cells were isolated from mouse blood by centrifugation (1,000 rpm) for 10 min. The obtained red blood cells were washed with Tris buffer for 3 times and then diluted to a final concentration of 5% (v / v). Hydrogels (500 μL) containing red blood cell stock solution (500 μL) were added to a 24-well microplate and then shaken at 150 rpm for 1 h at 37 °C. After centrifugation, the supernatant was introduced into a 96-well microplate. The absorbance of the solution was read by a microplate reader at 540 nm. 0.1% Triton x-100 was used as a positive control, while Tris buffer was used as a negative control. The hemolysis percentage was calculated according to the following relationship:

[0084] Hemolysis (%) = [(Ap-Ab) / (At-Ab)] x 100%

[0085] where Ap is the absorbance value of the experimental group, At is the absorbance value of Triton x, and Ab is the absorbance value of Tris buffer.

[0086] (10) H2O2 scavenging and O2 generation of hydrogels: The H2O2 decomposition ability of different formulations of hydrogels was evaluated using a typical Ti(SO4)2 colorimetric method. Hydrogels (1 mL) and H2O2 (1 mm, 1 mL) were mixed together and incubated in PBS at 37 °C. Then, 1.33 mL of 24% Ti(SO4)2 and 8.33 mL of H2SO4 were dissolved in 50 mL of deionized water to form a Ti(SO4)2 solution. At predetermined time points, 100 μL of supernatant of hydrogels was collected and 200 μL of Ti(SO4)2 solution was added to the supernatant. By measuring the absorbance at a wavelength of 405 nm, the concentration of H2O2 can be determined. Correspondingly, the O2 concentration in the above-mentioned supernatant was determined by an oxygen probe. -1 (11) Intracellular ROS consumption and oxygen generation: Intracellular ROS consumption and oxygen generation capacity of hydrogels were monitored by ROS-specific probe DCFH-DA and oxygen indicator Ru(dpp)3Cl2. HACAT cells were seeded into 6-well plates. In order to simulate the oxidative stress and hypoxic microenvironment of diabetic wounds in vitro, the cells were incubated with 100 μm H2O2 in a hypoxic environment (1% oxygen). After 3 days of treatment, DCFH-DA (10 μm, DMEM without FBS) was added to the wells and incubated at room temperature for 30 min. The fluorescence intensity representing the intracellular ROS content was observed by fluorescence microscopy. In addition, in order to evaluate the oxygen content in the cells, the sample was also incubated with oxygen probe [Ru(dpp)3Cl2] at a concentration of 10 μg mL

[0087] (12) In vivo hemostatic performance of hydrogel: A rat liver hemorrhage model was used to evaluate the hemostatic ability of the hydrogel. The rats were anesthetized, and then the liver was exposed from the abdominal incision, and the tissue fluid around the lesion was carefully removed using filter paper. The liver was placed on pre-weighed filter paper (W0), and then a biopsy needle (inner diameter 5 mm) and surgical scissors were used to form a defect (diameter 5 mm, height 4 mm) in the liver. Immediately after puncture, commercially available hemostatic sponges and hydrogels were placed at the bleeding site. Untreated wounds served as controls. The weight of the filter paper 60 seconds after puncture was measured (Wt). The amount of blood loss was calculated as the weight increase of the filter paper (Wt-W0).

[0088] (13) In vivo diabetic wound healing performance

[0089] Rats were intraperitoneally injected with streptozotocin (STZ) (50 mg / kg) for 5 consecutive days after overnight fasting. Blood glucose was measured 1 week later. When the non-fasting blood glucose level consistently exceeded 16.7 mM, the mice were considered diabetic mice. Diabetic mice were anesthetized and shaved with back hair. A full-thickness skin wound with a diameter of 10 mm was formed on each mouse using a punch biopsy. The mice were randomly divided into six groups and received different treatments, namely control group, OPH-AP group, OPH-AP@PTA@rGO@PDA group, OPH-AP@MnCoO@PLE@rGO@PDA group and OPH-AP@PTA@MnCoO@PLE@rGO@PDA group, each containing 8 mice. Wound healing was observed by taking photos at 0, 3, 7, 10, 15 after the wound was created. The wound area size was calculated using Image J software. The wound healing rate was calculated according to the following formula:

[0090] Wound healing rate = (W0-Wt) / W0 x 100%;

[0091] Wherein, W0 is the initial area of the wound, and Wt is the healing area of the wound.

[0092] III. Results

[0093] (1) Morphology of nanorods and nanoscale enzymes

[0094] The surface morphology of the synthesized nanomaterials was observed using TEM. As shown in Figure 1 a, the length of the PTA nanorods was about 1-5 μm, and the width was 1 μm. The nanoscale enzymes, on the other hand, exhibited a tetrahedral structure, with a visible coating around them.

[0095] (2) Preparation and FT-IR characterization of AP, OPH and AP-OPH

[0096] FTIR spectra were used to evaluate the functional groups of the polysaccharide structural units and the hydrogel. As shown in Figure 1b shows that the peak at 1726 cm -1 in the FT-IR spectrum of OPH is the stretching vibration of the -C-O bond of the aldehyde group, which proves the successful synthesis of OPH. Figure 1 c shows that the FTIR spectrum of AP has peaks at 1666 cm －1 (amide I) and 1595 cm －1 (amide II), and no carboxylate stretch. The peak at 2935 cm －1 indicates the presence of methylene symmetric C-H stretching vibration. This can be explained as an increase in C-H bond content after amidation reaction, indicating the success of the amidation treatment. For AP-OPH hydrogel, Figure 1 d gives the FT-IR spectra of hydrogels with different proportions, with a strong peak at 1622 cm -1 corresponding to C-N stretching vibration, showing the formation of Schiff base reaction. The peaks located at 2850 cm -1 and 2950 cm -1 are assigned to C-H stretching bands.

[0097] (3) Scanning electron micrograph (SEM) of hydrogel

[0098] The microstructure of the hydrogel was observed by scanning electron microscope SEM, and the results are shown in Figure 2 a, each group of hydrogel shows a porous structure, which is beneficial to the exchange of gas and cell growth and adhesion at the wound site, and can quickly absorb exudate at the wound site, providing a moist environment for the wound site. With the addition of drugs, the porosity of the hydrogel increases and the pore size decreases, among which the OPH-AP@PTA@MnCoO@PLE@rGO@PDA group shows the smallest pore size and the most dense porous structure.

[0099] (4) Evaluation of the injectability of the hydrogel

[0100] Figure 2 b shows that the AP-OPH hydrogel can be injected through a needle to a specific shape, indicating that the hydrogel has injection performance, the injection process is smooth, and there is no phenomenon of blockage, which is beneficial to the administration at the wound site. At the same time Figure 2 c also shows the state of the hydrogel after adding rGO@PDA coating.

[0101] (5) Thermal stability of the hydrogel

[0102] The thermal behavior of the OPH-AP hydrogel with different proportions can be divided into three stages Figure 3a) In the temperature range of 40-207 °C, water evaporation in the hydrogel resulted in a mass loss between 27.86% and 35.45%. At temperatures of 207-355 °C, the side chains of the hydrogel were broken, resulting in a percentage of mass loss between 59.34% and 54.20% in different hydrogels. The mass loss of the hydrogel between 355-800 °C can be attributed to the rupture of the main gel network. OPH:AP at 1:2 showed slightly better thermal stability than other pectins.

[0103] (6) Rheology of hydrogels

[0104] The rheological properties of the hydrogels were explored to assess their mechanical behavior. Different proportions of hydrogels showed a programmed decrease in viscosity under shear force (0.1-101 / s) (3b). OPP1 decreased from 203.14 Pa.s to 6.3374 Pa.s, OPP2 from 285.82 Pa.s to 10.718 Pa.s, OPP3 from 329.15 Pa.s to 13.646 Pa.s, OPP3@GO1 from 395.5 Pa.s to 10.2388 Pa.s, OPP3@GO2 from 399.6 Pa.s to 14.247 Pa.s, OPP3@GO3 from 426.82 Pa.s to 26.5972 Pa.s, indicating that the hydrogels have good injectability. On the other hand, the viscosity of the hydrogels increased with increasing amidated pectin concentration, indicating that the addition of pectin increased the crosslinking degree of the internal network of the hydrogels. Therefore, OPP3 was chosen for the graphene oxide coating, and the viscosity increased with increasing graphene concentration.

[0105] The dynamic cycle of bond formation and dissociation in the hydrogels contributes to the remodeling and self-healing activity, contrary to what happens in covalently linked hydrogels, these cycles can be attributed to the dynamic rearrangement of the Schiff base bonds in the OPH-AP network. The sweep test ( Figure 3 c) confirmed the gelation of the pectins, all the storage modulus (G') of the pectin gels exceeded the loss modulus (G"). This behavior can be attributed to the formation of a three-dimensional network structure. Gelation became more evident (G' > G") as the interactions in the hydrogels increased, especially

[0106] More connections were established between OPH-AP@PTA@MnCoO@PLE@rGO@PDA, which can explain the increase in G' values. The hydrogels have self-healing properties. As Figure 3As shown in d, the cyclic strain test of hydrogel data shows that G' is greater than G" at 1% strain, indicating that it is in the hydrogel state. Subsequently, when the shear strain increases to 200%, G' and G" decrease rapidly, indicating that the hydrogel structure is destroyed. In addition, after two cycles, when the shear strain returns to 1%, G' and G" return to the initial value, indicating the transition from sol state to gel state. This behavior is due to the physical crosslinking sites in the hydrogel that can adapt to different strains. These results show that the hydrogel has excellent mechanical properties such as self-healing and injectability, laying the foundation for its direct application on wounds.

[0107] (7) Swelling and degradation properties of hydrogel

[0108] The good water absorption capacity of the hydrogel enables it to maintain a moist environment for the wound, which is essential for better epidermal tissue repair. From the water absorption (WU) curves of the hydrogel ( Figure 4 a), the water absorption patterns of OPH-AP hydrogels with different proportions are similar, reaching equilibrium at 175 min. With the increase of pectin proportion, the water absorption capacity of the hydrogel increases: 8.205%, 9.765%, 12.675% respectively. The water retention curves of the hydrogel show ( Figure 4 b), the water retention performance of the pectin hydrogel is slightly stronger, 17.37%, 19.89%, 21.77% respectively. The reason why the absorption / dehydration performance of OPH-AP hydrogels with different proportions is different is that the increase of pectin content increases the crosslinking of the hydrogel, hindering the penetration of external water molecules into the interior of the hydrogel, and also hindering the penetration of water molecules in the interior of the hydrogel to the outside of the hydrogel. The results of water and dehydration show that the hydrogel has good water absorption and water retention capacity, and can effectively regulate and maintain the oxygen / nutrient supply and cell migration / adhesion / proliferation of the wound microenvironment (affecting skin remodeling and regeneration).

[0109] (8) Evaluation of DPPH radical scavenging rate of hydrogel

[0110] The polysaccharide with good antioxidant activity enables it to capture ROS in the wound with excessive inflammation and reduce oxidative stress, which plays a very important role in the smooth progress of wound healing. Figure 4 c shows that the scavenging rates of OPH and AP hydrogels with different proportions are 37.7%, 55.5% and 42.3% respectively. With the increase of AP concentration, the antioxidant efficiency also improves. With the increase of rGO@PDA concentration in the hydrogel, the antioxidant efficiency also gradually improves. When the concentration of rGO@PDA is 3 mg / mL, the DPPH scavenging rate of the hydrogel is the highest. Similar results were obtained in cells ( Figure 4 d), the above results confirm that the hydrogel has good antioxidant effect, and the antioxidant effect improves with the increase of AP and rGO@PDA content.

[0111] (9) Hydrogel biocompatibility

[0112] The basic feature of constructing hydrogel is its biocompatibility and controllable biodegradability. It is generally believed that the non-degradability of biomaterials implanted in vivo will cause long-term inflammatory reactions, so the ideal tissue engineering biomaterial scaffold should have good biodegradability and the ability to promote new tissue regeneration. Using mouse fibroblasts (NIH / 3T3), the effect of different proportions of OPH and AP hydrogels and different contents of rGO@PDA hydrogels on cell proliferation was studied by CCK-8 assay. From Figure 5 The quantitative statistical results of a can be seen that after co-culturing for 1 day, the cells in the OPH3 / GO3 hydrogel group reached a similar level to the control group. When the cells were further cultured for 3 days, the cell proliferation in the remaining groups was higher than that in the control group except for the OPH-AP1 and OPH-AP2 hydrogel groups. On the fifth day, the significant proliferation trend between the hydrogel group and the TCP group continued to expand (P<0.001), especially in the OPH3 / GO3 hydrogel group, indicating that not only AP, but also GO can promote the proliferation of NH3T3 cells.

[0113] (10) Hydrogel blood compatibility

[0114] The blood compatibility of the hydrogel was explored. Figure 5 b shows the hemolysis characteristics of the hydrogel. The positive control group is Triton TM X-100. The hemolysis rates of the AP-OPH1, AP-OPH2, AP-OPH3, OOP3 / GO1, OOP3 / GO2 and OOP3 / GO3 groups were 5.32%, 6.36%, 7.18%, 7.378%, 7.50%, 8.3%, respectively, which were close to 5.034% of the PBS group, indicating that the hydrogel was hemolysis safe. Combined with the above experimental results, we selected the hydrogel with OPH:AP of 1:5 and rGO@PDA of 3 mg / mL in the subsequent experiments.

[0115] (11) OPH-AP@PTA@MnCoO@PLE@rGO@PDA hydrogel continuously removes ROS

[0116] In order to correct the pathological accumulation of ROS and hypoxia in DFU at the same time, the hydrogel with enhanced catalase was designed as a H2O2-driven oxygen generator to promote diabetic wound healing. As Figure 6As shown in Fig. 8a, the pure hydrogel cannot show obvious H2O2 scavenging ability after 30 minutes of incubation. The characteristic absorption at 405 nm is enhanced with the increase of MnCoO@PLE nanoszyme, which proves that the MnCoO@PLE nanoszyme significantly endows the hydrogel with the ability to scavenge H2O2. In addition, we also detected the size of the hydrogel's ability to scavenge H2O2 when adding nanoszyme and nanorods at the same time. The results also found that when only adding nanorods, the hydrogel's ability to scavenge H2O2 was not obvious, while after adding different concentrations of nanoszyme, it showed the ability to scavenge ROS with the increase of concentration. However, the hydrogel added with nanorods also showed a certain ability to scavenge H2O2 compared with the blank hydrogel.

[0117] Exploring the H2O2 scavenging ability of hydrogel (3 mg / mL) Figure 6 b). It was observed that the concentration of H2O2 remained constant in the pure hydrogel. In sharp contrast, with the hydrogel and about 80% of H2O2 decomposed within the first 30 minutes and was observed to be essentially depleted within 200 minutes. It is noteworthy that the hydrogel can persistently catalyze H2O2. The hydrogel, due to its excellent catalytic stability, can effectively decompose H2O2 without reducing efficiency after repeated addition of H2O2. This phenomenon was also observed in the hydrogel added with nanoszyme and nanorods. Since the OPH-AP@PTA@MnCoO@PLE hydrogel can effectively catalyze H2O2 to produce O2, it can effectively repair the inflammatory stage and improve the hypoxic microenvironment of diabetic wounds.

[0118] (12) Hydrogel scavenging ROS to produce O2

[0119] Monitoring the ability of nanoszyme to produce O2 Figure 6 c, d). The MnCoO@PLE hydrogel showed oxygen generation after H2O2 treatment, while the nanorods did not show oxygen generation, indicating that the nanoszyme indeed played the role of catalase. In addition, the MnCoO@PLE / HA hydrogel can sustainably produce oxygen under the condition of repeated introduction of H2O2, indicating that it has excellent catalytic durability. These results firmly emphasize the hydrogel as a H2O2-driven oxygen generator and its potential application in clinics.

[0120] (13) Hydrogel protects skin cells from survival and proliferation in H2O2 and hypoxia-mediated in vitro diabetic microenvironment

[0121] To simulate the in vitro microenvironment of diabetic wounds, cells were incubated in a hypoxic environment (1% oxygen) with 100 μm H2O2. In this pathological microenvironment, cells were cultured with hydrogels containing PBS, OPH-AP, OPH-AP@PTA@rGO@PDA, OPH-AP@MnCoO@PLE@rGO@PDA, and OPH-AP@PTA@MnCoO@PLE@rGO@PDA, respectively. To investigate the dual role of the hydrogels in scavenging ROS and generating oxygen, changes in intracellular ROS and oxygen levels in HaCaT cells were assessed using the ROS-specific probe DCFH-DA and the oxygen indicator Ru(dpp)3Cl2. Figure 7 As shown, compared with the H2O2-hypoxia + PBS group and the H2O2-hypoxia + OPH-AP group, compared with

[0122] The green fluorescence intensity of HaCaT cells co-incubated with OPH-AP@MnCoO@PLE@rGO@PDA and OPH-AP@PTA@MnCoO@PLE@rGO@PDA hydrogels was significantly reduced (p<0.001), indicating that the hydrogels effectively inhibited intracellular ROS. Subsequently, the increase in intracellular oxygen was observed in OPH-AP@MnCoO@PLE@rGO@PDA and OPH-AP@PLE@rGO@PDA hydrogels.

[0123] The OPH-AP@PTA@MnCoO@PLE@rGO@PDA group showed significant oxygen generation, which was confirmed by the significant quenching of the fluorescence of [Ru(dpp)3Cl2].

[0124] (14) In vivo hemostatic ability of hydrogel

[0125] To more fully elucidate the in vivo hemostatic ability of the hydrogel described in this invention, a rat liver hemorrhage model was used. Figure 8 Significant blood loss was observed in control animals not treated with the hydrogel, manifested as large bloodstains on filter paper at the bleeding site. Conversely, the application of the hydrogel led to rapid cessation of blood loss; in comparison, the hemostatic effect of commercial alginate gels was inferior to that of the hydrogel described in this invention. Compared to the control group and the commercial gel group, the hydrogel described in this invention exhibited less blood loss and faster coagulation. These data indicate that the hydrogel, due to its high expansion rate, can easily isolate large amounts of blood. The cationic groups present in the gel can further enhance the accumulation of negatively charged red blood cells in the presence of coagulation.

[0126] OPH-AP@PTA@MnCoO@PLE@rGO@PDA hydrogel has lower clotting time and liver bleeding volume, and good hemostatic effect. Therefore, the multifunctional Codonopsis pilosula polysaccharide composite hydrogel can be used as a hemostatic gel in in vivo or in vitro wound hemostatic drugs.

[0127] (15) Hydrogel promotes skin wound repair

[0128] After a series of in vitro tests, further establish the in vivo wound model of diabetic foot to evaluate the actual promotion of wound healing by the hydrogel. With the commercially available traditional Chinese medicine Shengji cream as the control group, a series of in vitro tests were further established to evaluate the actual promotion of wound healing by the hydrogel. With the commercially available Tegaderm dressing as the control group, OPH-AP hydrogel, OPH-AP@PTA@rGO@PDA hydrogel, AP@MnCoO@PLE@rGO@PDA hydrogel, and AP@PTA@MnCoO@PLE@rGO@PDA hydrogel as the experimental group. From Figure 9 As can be seen from the above table, the wound area of each group gradually decreased with the increase of postoperative time. But the wound healing of the experimental group at each time point was significantly better than that of the control group. After 3 days of treatment, the wound area of the control group was significantly larger than the initial wound area, which continued until the 16th day of wound healing. This is consistent with the fact that diabetic wounds are difficult to heal in clinical practice and often continue to expand due to excessive inflammation. Since the wound site of the OPH-AP@PTA@MnCoO@PLE@rGO@PDA group has been completely re-epithelialized, and sebaceous glands and hair follicles have been generated; therefore, the multifunctional polysaccharide composite hydrogel of radix pseudostellariae can be applied in the preparation of drugs that promote the remodeling and functional reconstruction of collagen matrix of diabetic wound tissue.

[0129] The composition analysis of the above polysaccharide composite hydrogel of radix pseudostellariae is as follows:

[0130] (1) The hydrogel has good self-healing property and injectable characteristics through the spontaneous Schiff base reaction between the aldehyde group in OPH and the amino group in AP, which can effectively improve the stability of the wound dressing, facilitate drug administration at the wound site, and is more beneficial to the filling of irregular wounds, and can also prolong the use time of the wound material and improve the utilization rate of the biomaterial.

[0131] (2) The cationic group is introduced into the hydrogel by modifying MnCoO with ε-polylysine, and the positively charged ε-polylysine not only has antibacterial effect, but also can promote the aggregation of red blood cells, promote the coagulation at the wound site, and induce the occurrence of the first stage of wound repair (hemostasis).

[0132] (3) The provided hydrogel loaded with PTA and MnCoO@PLE presents a porous structure, which is beneficial to the exchange of gas, cell growth and adhesion at the wound site, has a higher swelling ratio, can quickly absorb the exudate at the wound site, reduce the bacterial contamination rate at the wound site, and provide a humid environment for the wound site by the water retention property of the hydrogel, thereby accelerating the wound repair.

[0133] (4) The hydrogel loaded with PTA and MnCoO@PLE provided has good antioxidant performance, can efficiently remove H2O2 to produce O2, can reduce the damage of ROS to the wound site, and reduce the inflammatory response in the diabetic wound.

[0134] (5) The hydrogel loaded with PTA and MnCoO@PLE (OPH-AP@PTA@MnCoO@PLE@rGO@PDA) provided has good blood compatibility and biocompatibility, achieves the effect of long-term sustained hemostasis, anti-inflammation, antioxidant, and repair promotion, thereby accelerating wound healing.

[0135] The above-described embodiments are merely preferred embodiments of the present application and are not intended to limit the scope of the present application. Various modifications and improvements to the technical solutions of the present application made by those of ordinary skill in the art without departing from the design spirit of the present application shall fall within the protection scope of the present application as defined by the claims.

Claims

1. A P. notoginseng polysaccharide composite hydrogel, characterized in that: The application relates to a hydrogel body, an active ingredient loaded in the hydrogel body and a functional coating, wherein the hydrogel body is prepared by mixing oxidized panax notoginseng polysaccharide OPH and amidated pectin polysaccharide AP according to a volume ratio of 1:1-2, the active ingredient is polytannin acid PTA and MnCoO@PLE, the MnCoO@PLE is prepared by the following method: adding manganese acetate tetrahydrate and polyvinylpyrrolidone into a mixed solution of ethanol and water, adding potassium hexacyanocobaltate (III) under intense stirring, keeping the reaction solution overnight, drying after centrifugation, dissolving the freeze-dried substance in ethanol to obtain solution A; dissolving ammonia in ethanol and stirring intensely to obtain solution B; adding solution B into solution A, then adding ethyl silicate, and centrifuging and freeze-drying after stirring; The freeze-dried substance is heated for 4 hours, then etched by using a NaOH aqueous solution, centrifuged and freeze-dried to obtain purified black powder, the epsilon-polylysine solution and the black powder aqueous solution are mixed together, and then ultrasonic treatment is conducted; The purified product is washed and centrifuged in a circulation mode and dried; the functional coating is polydopamine modified graphene oxide rGO@PDA; the PTA, the MnCoO@PLE and the rGO@PDA are loaded in the hydrogel body in an equal volume ratio.

2. The P. notoginseng polysaccharide composite hydrogel of claim 1, characterized in that: The volume ratio of the PTA, the MnCoO@PLE, the rGO@PDA and the OPH is 0.75-2.75:0.75-2.75:0.75-2.75:3.75-10. 3.The PPTC hydrogel of claim 1 or 2, characterized in that: The volume ratio of the PTA, the MnCoO@PLE, the rGO@PDA and the OPH is 1:1:1:5, and the mass ratio of the OPH to the AP is 1:

2. 4.The PPTC hydrogel of claim 1, wherein: The concentration of the rGO@PDA is 3 mg / mL.

5. The method for preparing the P. notoginseng polysaccharide composite hydrogel according to any one of claims 1-4, characterized in that: The PTA and the MnCoO@PLE are added into the OPH solution, then the AP solution and the rGO@PDA are added, and the product is obtained.

6. The method for preparing the Codonopsis pilosula polysaccharide composite hydrogel according to claim 5, characterized in that: The specific steps are as follows: (1) Preparation of OPH: oxidized panax notoginseng polysaccharide is prepared by a sodium periodate oxidation method; (2) Preparation of AP: pectin is dispersed in a mixture of ammonia and pre-cooled isopropyl alcohol solution and stirred intensely; after filtration, the pectin is resuspended in acidic isopropyl alcohol by magnetic stirring, stirred, filtered, washed with isopropyl alcohol and dried; (3) Preparation of PTA: tannin acid is dissolved in deionized water; the solution pH is adjusted by using potassium hydroxide; After continuous stirring, centrifugation and freeze-drying preservation; (4) Preparation of MnCoO@PLE: manganese acetate tetrahydrate and polyvinylpyrrolidone are added into a mixed solution of ethanol and water, potassium hexacyanocobaltate (III) is added under intense stirring, the reaction solution is kept overnight, dried after centrifugation, the freeze-dried substance is dissolved in ethanol to obtain solution A; ammonia is dissolved in ethanol and stirred intensely to obtain solution B; solution B is added into solution A, then ethyl silicate is added, and centrifugation and freeze-drying are conducted after stirring; The freeze-dried substance is heated for 4 hours, then etched by using a NaOH aqueous solution, centrifuged and freeze-dried to obtain purified black powder, the epsilon-polylysine solution and the black powder aqueous solution are mixed together, and then ultrasonic treatment is conducted; The purified product is washed and centrifuged in a circulation mode and dried to obtain MnCoO@PLE; (5) Preparation of rGO@PDA: graphene and dopamine hydrochloride were dissolved in Tris-HCl buffer and ultrasonicated for 30 min; the mixture was stirred vigorously at room temperature for 24 h; after centrifugation, it was washed with water and ethanol for several times, and finally freeze-dried to obtain rGO@PDA; (6) Preparation of hydrogel: PTA and MnCoO@PLE were added to the OPH solution, and then AP and rGO@PDA solution were added to obtain the composite hydrogel.

7. Use of the P. notoginseng polysaccharide composite hydrogel according to any one of claims 1-4 in the preparation of a reagent or a drug for removing O2 generated by reactive oxygen species.

8. Use of the P. notoginseng polysaccharide composite hydrogel according to any one of claims 1-4 in the preparation of a drug for improving the hypoxic microenvironment of a diabetic wound.

9. Use of the P. notoginseng polysaccharide composite hydrogel according to any one of claims 1-4 in the preparation of a hemostatic drug.

10. Use of the P. notoginseng polysaccharide composite hydrogel according to any one of claims 1-4 in the preparation of a drug for promoting the remodeling and functional reconstruction of the collagen matrix of a diabetic wound tissue.

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