Wound in-situ self-gelling multifunctional composite hemostatic powder and preparation method thereof

Abstract

The invention relates to wound in-situ self-gelling multifunctional composite hemostatic powder and a preparation method thereof, and belongs to the field of biological materials, the method comprises the following steps: S1, preparing modified hyaluronic acid through an oxidation reaction and grafting dopamine hydrochloride, dialyzing, freeze-drying and grinding into powder; s2, preparing super-assembled mesoporous silica loaded with the analgesic drug, and drying and grinding the super-assembled mesoporous silica to form powder; s3, uniformly mixing the modified hyaluronic acid powder, the carboxymethyl chitosan powder and the super-assembled mesoporous silica powder according to different mass ratios to obtain the multifunctional composite styptic powder. The hemostatic powder prepared by the method is simple in process, low in cost and relatively high in biological safety. In addition, the hemostatic powder also has the excellent characteristics of rapid self-gelation, wet tissue adhesion, coagulation promotion, antibiosis, analgesia and wound repair promotion.

Description

Technical Field

[0001] This invention relates to the field of biomaterials, specifically to a wound in-situ self-gelling multifunctional composite hemostatic powder and its preparation method. Background Technology

[0002] Severe hemorrhage caused by serious tissue trauma is a major cause of death in combat and civilian accidents, and rapid and effective hemostasis is crucial for improving patient survival rates. Although traditional methods such as surgical suturing are considered clinical standards, they rely on anesthesia preparation, are complex to perform, and are prone to causing secondary damage, making them unsuitable for the time-sensitive needs of pre-hospital emergency care. Ideal hemostatic materials not only need to possess instantaneous hemostasis and strong tissue adhesion, but also appropriate mechanical strength to maintain wound closure, while ensuring excellent biocompatibility.

[0003] Common hemostatic materials include gauze, hydrogels, sponges, and powders. While gauze is inexpensive and readily available, it lacks bioadhesion and typically requires continuous pressure for hemostasis. Hydrogel adhesives effectively seal wounds, and their moist, oxygen-permeable properties promote healing; however, continuous bleeding weakens the mechanical properties and adhesive strength of hydrogels, reducing their sealing effectiveness. Porous sponges have excellent blood absorption but are ill-suited for wounds with complex shapes. In contrast, powdered hemostatic agents offer advantages such as ease of use, rapid onset of action, portability, good storage stability, and suitability for irregular and incompressible bleeding wounds. However, some inorganic hemostatic powders (such as zeolite, montmorillonite, and bioglass) may be non-degradable, failing to form a strong physical seal on the wound surface, and potentially posing a risk of embolism, leading to hemostasis failure or serious harm to the human body. To overcome the inherent limitations of single-material application, researchers began exploring the combination of hydrogels' advantages in tissue adhesion, wound sealing, and mechanical support with the characteristics of powders, such as ease of filling irregular wounds, high blood absorption, efficient drug loading, and activation of coagulation cascades. This led to the development of the innovative concept of "self-gelling hemostatic powder." Self-gelling hemostatic powder combines the mechanical support, tissue adhesion, and wound sealing capabilities of hydrogels with the high liquid absorption and adaptability to filling irregular wounds found in powder materials. When applied to a wound, it rapidly transforms into an in-situ hydrogel, forming a strong seal on moist tissue surfaces and significantly improving hemostasis efficiency.

[0004] Polysaccharide materials have attracted widespread attention in the biomedical field due to their wide availability, low cost, ease of modification, and excellent biocompatibility, biodegradability, and non-toxicity. Among them, carboxymethyl chitosan not only possesses good antibacterial activity, wound-healing ability, and in vivo biocompatibility, but also accelerates hemostasis by aggregating erythrocytes, activating platelets, and promoting blood clot formation. Hyaluronic acid, with its excellent biocompatibility and biodegradability, plays a crucial role in tissue moisturizing, joint lubrication, and skin repair. Through oxidative modification of hyaluronic acid and modification with dopamine hydrochloride, highly reactive aldehyde and catechol groups can be introduced, thereby significantly enhancing the mechanical strength and tissue adhesion properties of the material after gelation through Schiff base crosslinking and electrostatic interactions.

[0005] On the other hand, inorganic hemostatic materials, represented by zeolites, silicates, kaolin, and silica, are also widely used in wound care due to their high hemostatic capacity, stability, and good biocompatibility. Porous silica, in particular, possesses a high specific surface area and porosity due to its tunable pore structure, significantly enhancing its adsorption capacity for liquids and proteins. The abundant silanol groups on its surface can also interact with coagulation factors through electrostatic interactions, activating intrinsic coagulation pathways and accelerating the coagulation cascade reaction. Furthermore, porous silica can also serve as a drug carrier, loading various therapeutic components to achieve synergistic effects between hemostasis and other therapeutic functions.

[0006] Based on the above analysis, combining the biofunctionality of polysaccharide materials with the structural advantages of inorganic materials holds promise for constructing a multifunctional composite material that combines rapid hemostasis, strong tissue adhesion, and wound healing promotion. The research and application of such materials are expected to bring significant technological breakthroughs to fields such as trauma treatment. Summary of the Invention

[0007] The purpose of this invention is to address the aforementioned problems in the prior art by providing a multifunctional composite hemostatic powder that can be rapidly self-gelled in situ at wound sites, and its preparation method. The hemostatic powder prepared by this method possesses excellent photothermal antibacterial activity, rapid coagulation, and strong tissue adhesion properties, while also meeting the comprehensive requirements of high biocompatibility, biodegradability, convenient preparation, low cost, and ease of use.

[0008] The objective of this invention is achieved through the following technical solution:

[0009] A method for preparing a wound-in-situ self-gelling multifunctional composite hemostatic powder, the method comprising the following steps:

[0010] S1: Hyaluronic acid is completely dissolved in water at 20~30℃, and sodium periodate is added to prepare oxidized hyaluronic acid through an oxidation reaction. After dialysis, freeze drying, pulverization and grinding and sieving, oxidized hyaluronic acid powder is obtained.

[0011] S2: Dissolve the oxidized hyaluronic acid powder obtained in step S1 completely in water at 20~30℃, add EDC and NHS and stir continuously. After complete dissolution, add dopamine hydrochloride to carry out amidation grafting reaction. The reaction solution is dialyzed, freeze-dried, pulverized and ground and sieved to obtain modified hyaluronic acid powder.

[0012] S3: Dissolve triethanolamine in water, heat and stir, then add hexadecyltrimethylammonium bromide and sodium salicylate and stir, then slowly add tetraethyl orthosilicate and stir continuously. The resulting white product is centrifuged, washed with deionized water and ethanol, calcined and thoroughly dried to obtain dendritic mesoporous silica (MSN).

[0013] S4: The MSN powder obtained in step S3 is dispersed in deionized water and ultrasonically treated to form a uniform dispersion. Lidocaine hydrochloride powder is dissolved in the MSN solution and stirred continuously. Then, ferric chloride hexahydrate solution and tannic acid solution are added to the complex system and stirred thoroughly. After centrifugation, drying and thorough grinding, super-assembled mesoporous silica powder is obtained.

[0014] S5: Modified hyaluronic acid powder, carboxymethyl chitosan powder and super-assembled mesoporous silica powder are mixed to obtain an in-situ self-gelling multifunctional composite hemostatic powder.

[0015] Further, in step S1, the mass ratio of hyaluronic acid to sodium periodate is 1:0.1~10.

[0016] Furthermore, in step S1, the molecular weight of the hyaluronic acid is 40~200 kDa, and the oxidation reaction time is 12~36 h.

[0017] Further, in step S2, the molar ratio of the oxidized hyaluronic acid powder, dopamine hydrochloride, EDC and NHS is 1:0.1~5:2~10:1~2.

[0018] Furthermore, in step S2, the temperature of the amidation grafting reaction is 25℃~40℃, the pH of the reaction solution is adjusted to 4~6 with dilute acid / base, and the reaction is carried out under a nitrogen atmosphere for 12~36 h.

[0019] Further, step S3 specifically involves: dissolving 50-400 mg of triethanolamine in 50 mL of deionized water at 60℃-90℃, heating and stirring for 15-60 min, then adding 200-800 mg of hexadecyltrimethylammonium bromide and 150-600 mg of sodium salicylate and stirring for 0.5-1.5 h, followed by slowly adding 4-12 mL of tetraethyl orthosilicate and stirring continuously for 5-10 h. The resulting white product is centrifuged, washed with deionized water and ethanol, calcined (600℃, 5 h), and thoroughly dried to obtain dendritic mesoporous silica (MSN).

[0020] Further, step S4 specifically involves: dispersing 50 mg of MSN powder obtained in step S3 in 20 mL of deionized water and ultrasonically treating it to form a uniform dispersion; dissolving 0.5–250 mg of lidocaine hydrochloride powder in the MSN solution and reacting it in the dark at 25–40 °C for 10–15 h; then adding 200 μL of 10–50 mmol / L ferric chloride hexahydrate solution and 200 μL of 10–50 mmol / L tannic acid solution to the complex system and stirring thoroughly; and obtaining superassembled mesoporous silica powder after centrifugation, drying, and thorough grinding.

[0021] Further, in step S5, the mass ratio of the modified hyaluronic acid powder, carboxymethyl chitosan powder, and super-assembled mesoporous silica powder is 1:2~4:0~2.

[0022] The advantages of this invention compared to existing technologies are as follows: The hyaluronic acid obtained through oxidation and grafting modification can rapidly form a hydrogel with high adhesion, good biocompatibility, and mechanical strength upon contact with blood via electrostatic interaction and Schiff base crosslinking, achieving physical sealing of wounds. Based on this, the introduced super-assembled mesoporous silica plays multiple key roles: firstly, its high porosity structure actively absorbs blood, concentrates clotting factors, and activates intrinsic clotting pathways, achieving a leap from "passive sealing" to "active coagulation promotion"; secondly, it significantly enhances the network structure of the hydrogel, enabling it to form a stable and reliable physical barrier in deep, irregular wounds subjected to blood flow impact. This material system, through integrated design, synergistically exerts multiple biological functions including procoagulation, strong adhesion, photothermal antibacterial properties, antioxidant properties, sustained analgesia, and healing promotion. Its preparation process is simple, the conditions are mild, and the cost is low. The product can be flexibly packaged in bags or tablets, offering advantages such as ease of use, injectability, and convenient storage and transportation. Therefore, this invention is not only applicable to surgical hemostasis of deep irregular bleeding and non-pressable areas, but also shows great clinical translational value and application potential in pre-hospital emergency care, war trauma and management of complex infected wounds. Attached Figure Description

[0023] Figure 1 Transmission electron microscopy image of the super-assembled mesoporous silica powder prepared in Example 1 of this invention;

[0024] Figure 2 The super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder prepared in Example 4 of this invention was induced to form a hydrogel in PBS and blood, and the results of the tube inversion experiment were used to verify its effectiveness in blocking water flow.

[0025] Figure 3 This is a schematic diagram illustrating the formation of a highly stable gel in situ on the surface of pigskin using the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder prepared in Example 4 of this invention.

[0026] Figure 4 Photothermal stability of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder prepared in Example 4 of this invention;

[0027] Figure 5 The antibacterial biofilm formation performance of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder prepared in Examples 1, 4 and Example 4 after photothermal treatment of the present invention is shown in the figure.

[0028] Figure 6 The in vitro hemostatic performance of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder prepared in Examples 1, 2, 3, 4 and 5 of this invention is shown in the figure.

[0029] Figure 7 The graph shows the performance of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder in Examples 1, 2, 3, 4 and 5 prepared in this invention in promoting L929 cell migration.

[0030] Figure 8 The in vivo degradation performance of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder prepared in Examples 1 and 4 of this invention in rats is shown in the figure.

[0031] Figure 9 The graph shows the hemostatic performance of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder prepared in Examples 1 and 4 of this invention in partial liver resection and femoral artery transection in rats.

[0032] Figure 10 The image shows the healing effect of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder prepared in Examples 1, 4 and Example 4 after photothermal treatment in a mouse wound model. Detailed Implementation

[0033] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments, but it is not limited thereto. Any modifications or equivalent substitutions to the technical solution of the present invention that do not depart from the spirit and scope of the technical solution of the present invention should be covered within the protection scope of the present invention.

[0034] Example 1

[0035] A method for preparing a modified hyaluronic acid / carboxymethyl chitosan / superassembled mesoporous silica composite hemostatic powder includes the following steps:

[0036] Step 1: At room temperature, dissolve 3 g of hyaluronic acid in 200 mL of deionized water and stir until completely dissolved. Then add 3.6 g of sodium periodate powder and react in the dark for 12 h. Subsequently, add 2 mL of ethylene glycol to terminate the reaction. Place the reaction solution into a dialysis bag with a molecular weight of 3500 and dialyze it in deionized water for 3 days. Afterward, freeze-dry, pulverize, grind, and pass through a 100-mesh sieve to obtain oxidized hyaluronic acid powder.

[0037] Step 2: Dissolve 1 g of oxidized hyaluronic acid powder in 100 mL of deionized water, then add 0.82 g of EDC and 0.25 g of NHS sequentially. Adjust the pH of the mixture to 5.5 using 0.1 mol / L HCl or NaOH, then add 0.81 g of dopamine hydrochloride. Stir the reaction under nitrogen protection for 8 h to inhibit the uncontrolled oxidation and self-polymerization of dopamine. After the reaction is complete, dialyze the mixture for 3 days using a dialysis bag with a molecular weight of 3500, then freeze-dry, pulverize, grind, and pass through a 100-mesh sieve to obtain modified hyaluronic acid powder.

[0038] Step 3: Add 50 mL of deionized water to an oil bath, heat to 80°C, then add 130 mg of triethanolamine and 760 mg of cetyltrimethylammonium bromide sequentially, stirring and heating continuously for 15 min. Then add 320 mg of sodium salicylate, and continue stirring for 1 h. Slowly add 8 mL of tetraethyl orthosilicate, maintaining the temperature and stirring for 6 h. After the reaction is complete, centrifuge at 10000 rpm for 10 min, and wash three times alternately with anhydrous ethanol and deionized water. Dry the product in an 80°C oven for 10 h, then calcine it in a muffle furnace at 600°C for 5 h to remove the surfactant, obtaining dendritic mesoporous silica (MSN).

[0039] Step 4: 50 mg of MSN powder was dispersed in 20 mL of deionized water and sonicated to form a uniform dispersion. 40 mg of lidocaine hydrochloride was dissolved in the MSN solution and sonicated to achieve uniform dispersion. The mixture was then reacted in the dark for 12 h to achieve drug loading. Subsequently, 200 μL of 24 mM / L tannic acid solution and ferric chloride hexahydrate solution were added sequentially to continue the reaction and form a superassembled structure. The mixture was centrifuged (10000 rpm, 10 min) and washed three times with deionized water. After drying and thorough grinding, the superassembled mesoporous silica powder was obtained.

[0040] Step 5: Mix modified hyaluronic acid powder, carboxymethyl chitosan and super-assembled mesoporous silica powder in a mass ratio of 2:1:0 to obtain an in-situ self-gelling multifunctional composite hemostatic powder.

[0041] The antibacterial biofilm formation ability of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder obtained in this embodiment was evaluated by an experiment. The specific method is as follows: First, a hydrogel was prepared by adding 40 mg of the composite powder and 320 μL of deionized water to a 12-well plate and then sterilizing it by ultraviolet irradiation. Subsequently, following the standard bacterial biofilm formation experimental procedure, Staphylococcus aureus and Escherichia coli bacterial suspensions (1×10⁻⁶) were inoculated onto the surface of the above sample, respectively. 8 (CFU / mL), and incubated at 37°C for 24 hours to promote biofilm formation.

[0042] To observe the morphology and bacterial viability of the biofilm, the incubated samples were double-stained for 30 minutes under light-protected conditions using the green fluorescent dye SYTO9 and the red fluorescent dye PI. SYTO9 labeled live bacteria, while PI labeled dead bacteria. After staining, the samples were gently rinsed three times with PBS to remove unbound dye. Finally, a confocal laser scanning microscope was used to perform a three-dimensional scan of the stained biofilm to obtain its spatial structure image, which was used to analyze the biofilm formation and the inhibitory effect of the composite hemostatic powder on it.

[0043] The adhesion strength of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder obtained in this embodiment on a moist tissue surface was evaluated using the following method: The lap shear test method was employed, with pigskin as a simulated tissue substrate to evaluate its adhesion performance. First, fresh pigskin was cut into rectangular strips measuring 15 mm × 35 mm. Before the test, approximately 200 µL of water was added to the surface of the pigskin to simulate a moist tissue environment. Subsequently, 30 mg of the composite hemostatic powder sample was accurately weighed and evenly spread over a pre-defined 10 mm × 10 mm adhesion area. Another strip of pigskin of the same size was placed on top of the powder, and a constant pressure was continuously applied for 5 minutes to ensure uniform stress at the bonding interface. The adhesion strength test was conducted at room temperature using an electronic universal testing machine. The testing machine applied tension to the sample at a tensile speed of 10 mm / s until the two layers of pigskin completely separated, and the maximum load during this process was recorded. The adhesion strength was calculated by the ratio of the maximum load to the bond area (10 mm × 10 mm).

[0044] The in vitro procoagulant performance evaluation experiment of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder obtained in this embodiment was conducted as follows: First, anticoagulated mouse whole blood was mixed with 0.1 M CaCl2 solution at a volume ratio of 9:1 to prepare a calcification working solution. Then, 50 µL of this working solution was added to a 96-well plate and pre-incubated at 37°C. Next, 15 mg of the test material powder was added and gently mixed by pipetting to initiate the coagulation process. The reaction system was incubated at 37°C for 0.5, 1, 1.5, 2, 3, and 4 minutes, respectively. At each predetermined time point, the plate was gently rinsed with preheated PBS. If a strong blood clot formed at the bottom of the well and resisted PBS rinsing, coagulation was considered complete.

[0045] The in vivo hemostatic effect evaluation experiment of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder obtained in this embodiment includes the following steps:

[0046] ① Anesthetize rats by intraperitoneal injection of 0.9 mL of 10% chloral hydrate;

[0047] ② Expose the liver or femoral artery and remove surrounding tissue fluid; use a scalpel to create a wound model of the specified size on its surface:

[0048] Liver single incision bleeding model: a single linear wound with a depth of 3 mm and a length of 10 mm was created;

[0049] Complete transection of the femoral artery hemorrhage model: The femoral artery in the leg of a rat was exposed, fully separated, and completely transected to simulate rapid bleeding caused by damage to a large blood vessel;

[0050] ③ After the wound model is established, wipe away the blood with gauze immediately, then place 50 mg of hemostatic powder on the wound surface and press gently for 10 seconds;

[0051] ④ Record the bleeding situation within 0-5 minutes. For some models, record images or videos simultaneously to intuitively evaluate the dynamic hemostatic performance of the hemostatic material.

[0052] The in vitro cell migration experiment of the superassembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder obtained in this embodiment was conducted as follows: L929 cells were seeded in 6-well plates and cultured until a dense monolayer was formed. Then, a straight scratch was made on the cell monolayer using a 200µL sterile pipette tip, and the cells were washed with PBS to remove detached cells. Next, 2 mL of material extraction medium (15 mg / mL) was added to each well, and the cells were cultured further. During the 24-hour observation period, cell migration was monitored using a microscope, and images of the scratch were taken at specified time points to measure the scratch width.

[0053] The in vivo degradation performance evaluation experiment of the superassembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder obtained in this embodiment was conducted as follows: To evaluate the in vivo degradation performance of the material, a sterile hydrogel was subcutaneously implanted into rats. On days 7 and 14 post-implantation, the implant was scanned using a color Doppler ultrasound diagnostic system. The thickness of the implant was measured using the accompanying software, and the images were recorded.

[0054] The in vivo wound healing performance evaluation experiment of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder obtained in this embodiment was conducted as follows: A full-thickness skin defect model of the mouse back was used, and a circular wound with a diameter of 8 mm was prepared on each side of the dorsal midline. Kunming mice (female, weighing 25-30 g) were fully anesthetized, their back hair was shaved, and a circular full-thickness skin defect wound with a diameter of 8 mm was made on each side of the dorsal midline. Appropriate wound dressings were then applied. Images of the wounds were taken on days 3, 7, and 14 post-injury, and the wound area was calculated using ImageJ software to monitor wound healing. The wound contraction rate (%) was calculated using the following formula:

[0055]

[0056] The analgesic effect of the super-assembled silica / carboxymethyl chitosan / modified hyaluronic acid composite hemostatic powder obtained in this embodiment was evaluated using the following method: The analgesic effect of the material was evaluated using an acetic acid-induced mouse writhing test. First, the composite powder was mixed with physiological saline to prepare a powder with an area of ​​2 cm². 2Circular hydrogel patches were applied to the abdomen of mice after careful shaving of the abdominal hair, and then Tegaderm was used. TM The film was fixed in place. After 3 hours, the patch was removed, followed by an intraperitoneal injection of 0.6% (v / v) acetic acid solution (10 mL / kg) to induce a writhing response. Control mice received the same dose of acetic acid and had Tegaderm applied to their abdomens in the same manner. TM Membrane. Record the number of writhing movements (W) in mice within 30 minutes after injection, and calculate the analgesic inhibition rate (PIR) using the following formula:

[0057]

[0058] in, and The number of writhing movements in mice in the control group and the material treatment group are respectively.

[0059] Example 2

[0060] In this embodiment, the preparation methods of modified hyaluronic acid powder and super-assembled mesoporous silica powder are basically the same as those in Example 1. Finally, the modified hyaluronic acid powder, carboxymethyl chitosan and super-assembled mesoporous silica powder are mixed in a mass ratio of 2:1:0.25 to obtain an in-situ self-gelling multifunctional composite hemostatic powder.

[0061] Example 3

[0062] In this embodiment, the preparation methods of modified hyaluronic acid powder and super-assembled mesoporous silica powder are basically the same as those in Example 1. Finally, the modified hyaluronic acid powder, carboxymethyl chitosan and super-assembled mesoporous silica powder are mixed in a mass ratio of 2:1:0.5 to obtain an in-situ self-gelling multifunctional composite hemostatic powder.

[0063] Example 4

[0064] In this embodiment, the preparation methods of modified hyaluronic acid powder and super-assembled mesoporous silica powder are basically the same as those in Example 1. Finally, the modified hyaluronic acid powder, carboxymethyl chitosan and super-assembled mesoporous silica powder are mixed in a mass ratio of 2:1:0.75 to obtain an in-situ self-gelling multifunctional composite hemostatic powder.

[0065] Example 5

[0066] In this embodiment, the preparation methods of modified hyaluronic acid powder and super-assembled mesoporous silica powder are basically the same as those in Example 1. Finally, the modified hyaluronic acid powder, carboxymethyl chitosan and super-assembled mesoporous silica powder are mixed in a mass ratio of 2:1:1 to obtain an in-situ self-gelling multifunctional composite hemostatic powder.

[0067] The results of measurements in Examples 1-5 were analyzed, and the analysis is as follows:

[0068] Figure 1 The results indicate that the superassembled silica surface contains nitrogen and iron elements, demonstrating the successful loading of lidocaine hydrochloride and the successful encapsulation of the metal phenolic shell.

[0069] Figure 2 The results showed that the prepared composite powder could rapidly self-gel and physically block water flow.

[0070] Figure 3 The study demonstrated that the composite powder can rapidly form a hydrogel in situ on the surface of wet pigskin, and exhibits high stability after stretching, torsion, and bending.

[0071] Figure 4 Example 4 demonstrates good repeatable photothermal stability.

[0072] Figure 5 This indicates that Example 4 under photothermal conditions has good antibacterial biofilm formation ability.

[0073] Figure 6 This indicates that all embodiments have a significant coagulation-promoting effect, with Embodiment 4 showing the best effect.

[0074] Figure 7 This indicates that all embodiments have good L929 cell compatibility and cell migration promotion ability, with embodiment 4 showing the best effect.

[0075] Figure 8 This indicates that both Example 1 and Example 4 can be degraded in rats, and Example 4 can be completely metabolized within two weeks.

[0076] Figure 9 This indicates that Example 4 has good hemostatic effects in both the rat liver single-incision bleeding model and the femoral artery transection bleeding model.

[0077] Figure 10 This indicates that Example 4, which has undergone photothermal treatment, has a good effect on promoting wound healing in mice.

Claims

1. A method for preparing a wound-in-situ self-gelling multifunctional composite hemostatic powder, characterized in that: The method includes the following steps: S1: Hyaluronic acid is completely dissolved in water at 20~30℃, and sodium periodate is added to prepare oxidized hyaluronic acid through an oxidation reaction. After dialysis, freeze drying, pulverization and grinding and sieving, oxidized hyaluronic acid powder is obtained. S2: Dissolve the oxidized hyaluronic acid powder obtained in step S1 completely in water at 20~30℃, add EDC and NHS and stir continuously. After complete dissolution, add dopamine hydrochloride to carry out amidation grafting reaction. The reaction solution is dialyzed, freeze-dried, pulverized and ground and sieved to obtain modified hyaluronic acid powder. S3: Dissolve triethanolamine in water, heat and stir, then add hexadecyltrimethylammonium bromide and sodium salicylate and stir, then slowly add tetraethyl orthosilicate and stir continuously. The resulting white product is centrifuged, washed with deionized water and ethanol, calcined and thoroughly dried to obtain dendritic mesoporous silica (MSN). S4: The MSN powder obtained in step S3 is dispersed in deionized water and ultrasonically treated to form a uniform dispersion. Lidocaine hydrochloride powder is dissolved in the MSN solution and stirred continuously. Then, ferric chloride hexahydrate solution and tannic acid solution are added to the complex system and stirred thoroughly. After centrifugation, drying and thorough grinding, super-assembled mesoporous silica powder is obtained. S5: Modified hyaluronic acid powder, carboxymethyl chitosan powder and super-assembled mesoporous silica powder are mixed to obtain an in-situ self-gelling multifunctional composite hemostatic powder.

2. The preparation method according to claim 1, characterized in that: In step S1, the mass ratio of hyaluronic acid to sodium periodate is 1:0.1~10.

3. The preparation method according to claim 1, characterized in that: In step S1, the molecular weight of the hyaluronic acid is 40~200 kDa, and the oxidation reaction time is 12~36 h.

4. The preparation method according to claim 1, characterized in that: In step S2, the molar ratio of the oxidized hyaluronic acid powder, dopamine hydrochloride, EDC and NHS is 1:0.1~5:2~10:1~2.

5. The preparation method according to claim 1, characterized in that: In step S2, the amidation grafting reaction is carried out at a temperature of 25°C to 40°C, the pH of the reaction solution is adjusted to 4 to 6 using dilute acid / alkali, and the reaction is carried out under a nitrogen atmosphere for 12 to 36 hours.

6. The preparation method according to claim 1, characterized in that: Step S3 specifically involves dissolving 50-400 mg of triethanolamine in 50 mL of deionized water at 60℃-90℃, heating and stirring for 15-60 min, then adding 200-800 mg of hexadecyltrimethylammonium bromide and 150-600 mg of sodium salicylate and stirring for 0.5-1.5 h, followed by slowly adding 4-12 mL of tetraethyl orthosilicate and stirring continuously for 5-10 h. The resulting white product is centrifuged, washed with deionized water and ethanol, calcined (600℃, 5 h), and thoroughly dried to obtain dendritic mesoporous silica (MSN).

7. The preparation method according to claim 1, characterized in that: Step S4 specifically involves: dispersing 50 mg of MSN powder obtained in step S3 in 20 mL of deionized water and ultrasonically treating it to form a uniform dispersion; dissolving 0.5–250 mg of lidocaine hydrochloride powder in the MSN solution and reacting it in the dark at 25–40 °C for 10–15 h; then adding 200 μL of 10–50 mmol / L ferric chloride hexahydrate solution and 200 μL of 10–50 mmol / L tannic acid solution to the complex system and stirring thoroughly; and finally obtaining superassembled mesoporous silica powder by centrifugation, drying, and thorough grinding.

8. The preparation method according to claim 1, characterized in that: In step S5, the mass ratio of the modified hyaluronic acid powder, carboxymethyl chitosan powder, and super-assembled mesoporous silica powder is 1:2~4:0~2.

Images