Highly adherent porous sponges and methods of making and using the same

Abstract

The application discloses a kind of high-adhesion porous sponges and its preparation method and application, which combines the advantages of temperature-responsive gelatin microgel and porous sponge material, gelatin microgel is prepared at low temperature and loaded into sponge, when contacting blood environment, gelatin microgel will quickly dissolve, restore its polymer segment, then, chemical reaction occurs with soluble ingredients in sponge, and reacts with wound tissue through covalent bond and non-covalent bond, thereby firmly anchoring sponge to wound, solving the problem that traditional hemostatic sponge cannot stably adhere on wet wound.Compared with traditional hemostatic method, the application does not need external pressure assistance, and can achieve blood coagulation and stable adhesion of wound in a short time, avoiding secondary damage to fragile internal organs caused by long-term pressing.

Description

Technical Field

[0001] This invention relates to the field of biomaterials technology, specifically to highly adhesive porous sponges, their preparation methods, and applications. Background Technology

[0002] Internal organs such as the liver, spleen, and kidneys are prone to massive bleeding after trauma due to their fragile texture and rich blood supply, which can be life-threatening. Compared to harder tissues like limbs, internal organs have a looser tissue structure, resulting in a wider distribution of bleeding points. Currently, commonly used absorbent hemostatic materials in clinical practice, such as medical gauze and gelatin sponges, can quickly absorb blood and tissue fluid from the wound, aiding in hemostasis. Procoagulant hemostatic materials, such as clotting proteins and clotting factors, achieve hemostasis by promoting blood coagulation. Although traditional hemostatic materials can control bleeding to some extent, they usually require external pressure to function and often rely on the patient's own clotting ability. This dependence leads to prolonged hemostasis time and can easily cause secondary damage to fragile internal organs during prolonged pressure. Furthermore, for internal bleeding, because the bleeding point is located inside the body and the wound surface is moist, hemostatic materials lacking adhesive properties are difficult to stably fix to the bleeding point, resulting in unsatisfactory hemostatic effects.

[0003] The application of hemostatic materials becomes even more challenging when dealing with massive bleeding, deep trauma, and irregular wounds. This is because the surface of bleeding tissue is usually covered with blood, tissue fluid, and other liquids, which hinder the normal adhesion of hemostatic materials. To address this challenge, adhesive patch-type hemostatic materials have emerged. These materials can adhere to the wound tissue through covalent or non-covalent interactions (such as ionic and hydrogen bonds) with tissue surface groups (e.g., primary amino, carboxyl, and thiol groups), thereby achieving hemostasis. However, in cases of massive bleeding, the wound surface is often covered with blood, greatly limiting the adhesion of hemostatic materials on moist wounds. This wet adhesion presents significant technical challenges, especially when dealing with deep trauma or large-area bleeding.

[0004] To address these issues, researchers have proposed porous sponges as a hemostatic material. Porous hemostatic sponges possess excellent liquid absorbency, absorbing blood upon contact with the sponge, effectively enriching the local blood supply and achieving moisture absorption of the wound surface. However, traditional solid sponge materials cannot directly adhere to the wound surface, especially in visceral trauma under high humidity conditions, where the stability and hemostatic effect of the sponge material are often limited. Therefore, developing sponges with good adhesion after absorbing blood is crucial for the development of novel hemostatic materials. Summary of the Invention

[0005] To address the technical deficiencies of existing technologies, this invention provides a highly adhesive porous sponge, its preparation method, and its application. This solves the problem that traditional hemostatic sponges cannot stably adhere to moist wound surfaces. Compared to traditional hemostasis methods, this invention does not require external pressure and can achieve blood coagulation and stable adhesion to the wound surface in a short time, avoiding secondary damage to fragile internal organs caused by prolonged pressure.

[0006] The technical solution adopted in this invention is: a high-adhesion porous sponge, wherein the high-adhesion porous sponge is a modified starch sponge loaded with microgel, wherein calcium silicate is loaded on the microgel, and the microgel accounts for 50% of the mass percentage of the modified starch sponge in the high-adhesion porous sponge.

[0007] The modified starch in the modified starch sponge is norbornene-grafted starch St-Nor and oxidized starch OSt.

[0008] The microgel is a gelatin microgel.

[0009] The mass ratio of the microgel to its loaded calcium silicate is 10:1.

[0010] A method for preparing a highly adhesive porous sponge includes the following steps:

[0011] S1. Preparation of modified starch porous sponge: Modified starch was dissolved in PBS containing PI 2959. At room temperature, HS-PEG-SH and Pranic were dissolved in PBS and mixed with the modified starch solution. After centrifugation and defoaming, carbon dioxide was used for pressurized foaming. The solution was released into a mold and allowed to stand. After irradiation under ultraviolet light, primary curing was completed. The cured material was freeze-dried to obtain modified starch sponge (SSP).

[0012] S2. Preparation of gelatin microgels: Gelatin and calcium silicate were dissolved in purified water to prepare an aqueous phase. Liquid paraffin containing 1% Span-80 was used as the oil phase. The volume ratio of the aqueous phase to the oil phase was 1:20. Under water bath conditions, the aqueous gelatin solution was slowly added dropwise to the preheated oil phase to emulsify and form a uniform white emulsion. The entire system was rapidly cooled to 4°C and stirred continuously. After completion, the lower gel solution was collected by low-temperature and low-speed centrifugation, which is the gelatin microgel (GMH).

[0013] S3. Preparation of adhesive gel: Gelatin microgels were dispersed in cold water at 4°C. Modified starch sponge SSP was immersed in the gelatin microgels. After vacuum extraction, it was washed with cold water, freeze-dried, and finally a highly adhesive porous sponge loaded with microgels was obtained.

[0014] The modified starch is norbornene-grafted starch St-Nor and oxidized starch OSt, with a mass ratio of norbornene-grafted starch St-Nor to oxidized starch OSt of 3:2.

[0015] In step S1, the wavelength of the ultraviolet irradiation is 365 nm, and the power is 15 mW·cm. 2 .

[0016] In step S1, the concentration of PI 2959 is 0.1 wt%.

[0017] In step S3, the microgel accounts for 50% of the mass percentage of the modified starch sponge.

[0018] Application of a highly adhesive porous sponge in the preparation of a hemostatic material for moist wounds.

[0019] The beneficial effects of this invention are as follows: This invention provides a highly adhesive porous sponge, its preparation method, and its application. It combines the advantages of temperature-responsive gelatin microgels and porous sponge materials. By preparing gelatin microgels at low temperatures and loading them into the sponge, the gelatin microgels will quickly dissolve upon contact with a blood environment, restoring their polymer chains. Subsequently, they will chemically react with the soluble components within the sponge and react with the wound tissue through covalent and non-covalent bonds, thereby firmly anchoring the sponge to the wound surface. This solves the problem that traditional hemostatic sponges cannot stably adhere to moist wound surfaces. Compared with traditional hemostasis methods, this invention does not require external pressure assistance and can achieve blood coagulation and stable adhesion to the wound surface in a short time, avoiding secondary damage to fragile internal organs caused by prolonged pressure.

[0020] Secondly, microgels are not only an important component of sponge adhesion, but also a carrier. With the help of microgels, procoagulant active ingredients can be loaded into the sponge system. As the microgels responsively disintegrate, the active ingredients are rapidly released and activate the coagulation cascade reaction, thereby accelerating the hemostasis process.

[0021] Third, the loaded procoagulant active ingredient is calcium silicate. Compared with biological agents such as thrombin, its advantages are high stability and negative charge on the surface, which can activate coagulation factor 12. Most importantly, the weakly alkaline environment provided by the hydrolysis of calcium silicate is the best condition for the reaction between gelatin microgels and soluble components in the sponge, allowing this reaction to occur more quickly. Attached Figure Description

[0022] Figure 1 The microstructure, porosity, and water / blood absorption properties of the sponges are shown in the following figures: (a) Scanning electron microscope images of the four sponges at 100x and 1000x magnification; (b) Porosity results of the four sponges; (c) Liquid absorption-time curves of the four sponges for PBS; (d) Liquid absorption-time curves of the four sponges for rabbit blood.

[0023] Figure 2The expansion properties of the sponges are shown in the following images: (a) images of the four sponges in their initial state, compressed state, and expanded state under PBS and blood triggering; (b) SEM images of the four sponges in their initial state, compressed state, and expanded state under PBS triggering; (c) expansion time of the four sponges under PBS triggering; and (d) expansion time of the four sponges under blood triggering.

[0024] Figure 3 The compression properties of the sponge are as follows: (a) uniaxial compressive stress-strain curves of the four sponges; (be) stress-strain cycle (10 times) curves of the four sponges at 80% compressive strain; and (f) maximum compressive stress of the four sponges at 80% strain.

[0025] Figure 4 The shear strength of the sponge overlapping on pigskin.

[0026] Figure 5 The study aimed to test the in vitro coagulation properties and platelet and erythrocyte adhesion ability of sponges; (a) in vitro coagulation time of different groups; (b) in vitro coagulation index of different groups; and (c) SEM images of platelet and erythrocyte adhesion of the four groups of sponges.

[0027] Figure 6 The hemostatic effect of sponge in the liver laceration bleeding model of SD rats is shown in the following images: (a) Hemostasis process of different groups of samples in the liver of SD rats; (b) Statistical results of bleeding volume of different groups of samples in the liver of SD rats; (c) Images of different groups of samples after hemostasis in the liver of SD rats.

[0028] Figure 7 The hemostatic effect of sponge in the femoral artery laceration bleeding model of SD rats is shown in the figure. (a) Hemostasis process of the sample in the femoral artery of SD rats; (b) Statistical results of hemostasis time of different groups of samples in the liver of SD rats; (c) Statistical results of bleeding volume of different groups of samples in the liver of SD rats. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1

[0031] Porous sponge preparation process: First, modified starch (30g norbornene-grafted starch St-Nor + 20g oxidized starch OSt) was dissolved in 500ml of PBS (pH=7.4, 0.01 M) containing PI 2959 (0.1wt%). At room temperature, 10g HS-PEG-SH and 0.1g Pluronic were dissolved in 50ml of PBS (pH=7.4, 0.01 M) and mixed with the modified starch solution. After centrifugation and defoaming, the mixture was transferred to a high-pressure foaming tank, pressurized with carbon dioxide, and the solution was released into a mold through the outlet. After standing for 1 minute, the mixture was then subjected to ultraviolet light (wavelength: 365nm, power: 15 mW·cm⁻¹). 2 The material was irradiated for 300 seconds to complete the initial curing. The cured material was then freeze-dried to obtain modified starch sponge (SSP).

[0032] Preparation process of gelatin microgels: 100g of bovine bone-derived gelatin (type B) and 10g of calcium silicate were dissolved in 1000ml of purified water to prepare an aqueous phase. Liquid paraffin containing 1% Span-80 was used as the oil phase, with an aqueous phase to oil phase ratio of 1:20. Under a 50℃ water bath, the gelatin solution was slowly added dropwise to the preheated oil phase, and emulsified at 400rpm for 30min to form a uniform white emulsion. The entire system was rapidly cooled to 4℃ and stirred continuously for 30min. After completion, the lower gel layer was collected by low-temperature, low-speed centrifugation, which is the gelatin microgel (GMH).

[0033] Adhesion gel preparation process: The microgel was dispersed in cold water at 4℃. The SSP was immersed in GMH solution according to different ratios of sponge and gel. After vacuum extraction for 30 min, the sponge was washed with cold water, freeze-dried, and finally the sponge loaded with microgel was obtained (GMH0 / SSP, GMH20 / SSP, GMH50 / SSP, GMH100 / SSP, where the value represents the mass percentage of GHM in the sponge).

[0034] Experimental characterization:

[0035] SEM: The prepared sponge was attached to the sample stage, a thin layer of gold was sputtered onto it, and then analyzed and observed using a scanning electron microscope.

[0036] Liquid absorption ratio: All dried sponges were weighed before the experiment (W0), and then immersed in PBS or rabbit whole blood for a certain period of time. The sponges were then removed, gently smeared on filter paper to remove excess liquid, and the final weight of the sponge was recorded as W1. The formula for calculating the liquid absorption ratio is as follows:

[0037] Porosity: Immerse the pre-weighed sponge sample in a certain amount of ethanol for 30 minutes, then remove the sponge and weigh it again. The formula for calculating porosity (P) is as follows:

[0038]

[0039] in N 0 and N 1 represents the weight of the sponge before and after immersion in ethanol. V 0 represents the volume of the sponge sample, and ρ represents the density of ethanol (0.785 g / cm³). 3 ).

[0040] Volume expansion performance: The volume expansion effect and expansion time of sponges triggered by PBS or blood were measured. First, all sponges were compressed to the same volume and shape. PBS or rabbit whole blood was then dripped onto the sponges using a syringe until excess liquid drained out. The volume expansion process triggered by PBS or blood was recorded via video, and the time required for expansion recovery was calculated. The initial, compressed, and expanded microstructures of the PBS group samples were observed using SEM.

[0041] Mechanical strength: In the compression test, a cylindrical sponge was compressed to 80% strain at a rate of 10 mm / min. In the cyclic compression test, a cylindrical sponge of the same size was compressed to 80% strain at a rate of 10 mm / min, and then restored to 0% strain at the same rate. This cycle was repeated ten times. The stress-strain curves for all tests were recorded.

[0042] Adhesion strength: A pigskin specimen measuring 80 × 10 mm was used. Before the test, the sample was attached to the pigskin, and an appropriate amount of physiological saline was added. Then, the sample was placed in the middle of the pigskin, and a certain force was applied to one side to ensure that the other piece was connected by an overlapping shear method. After waiting for 10 minutes, the tensile adhesion strength in the overlapping shear direction was tested on a universal testing machine, and the maximum stress before the bonded joint failed was recorded.

[0043] Clotting time: 5 mg of sponge was incubated with 200 μl of citrate-treated whole blood from rabbits in a plastic bottle at 37°C. Then, 20 μl of 0.1 M calcium chloride solution was added to the blood, starting at the designated time. Every 10 seconds, the bottle was tilted to observe blood flow. The time to coagulation was recorded.

[0044] Coagulation Index (BCI): 100 μl of citrated whole blood from rabbits was added to a sponge containing 20 mg of solution, followed by 10 μl of 0.1 M calcium chloride solution. After incubation for 30 min, 25 ml of deionized water was added to a culture dish to wash away any uncoagulated blood. Finally, the uncoagulated blood solution was collected, and its OD value at 540 nm was measured (ODsambe). The OD value of 100 μl of citrated whole blood in 25 ml of deionized water was used as a blank control (OD control). The formula for calculating BCI is as follows:

[0045]

[0046] Platelet adhesion: 20 mg of sample was placed in a 24-well plate and incubated with 500 μl of platelet-rich plasma (PRP) at 37 °C for 30 min. Non-adhering platelets were then thoroughly washed with PBS. Subsequently, the PRP-incubated sample was fixed with 2 ml PBS containing 2.5% glutaraldehyde and then dehydrated with a series of fractionated ethanol solutions (50%, 75%, 80%, 90%, and 100%). Finally, all samples were characterized by scanning electron microscopy.

[0047] Red blood cell adhesion: 20 mg of sample was incubated with 500 μl of diluted red blood cell solution for 30 min. Then, non-adherent red blood cells were removed with PBS. The red blood cells were fixed in 2.5% glutaraldehyde PBS solution, then graded, dehydrated and dried in ethanol, and the morphology of adherent red blood cells was observed using scanning electron microscopy.

[0048] Hemostasis of the liver in SD rats: Rats were anesthetized with a styrax anesthetic. Abdominal hair was then shaved, the abdominal cavity was opened to expose the liver, and a pre-weighed gauze was placed at the base of the liver. A 5mm x 3mm incision was made in the liver using a scalpel. After bleeding stabilized, a commercially available sponge was applied to the wound (in the experimental group, the sponge was applied without any additional force), and the blood loss of the rats was recorded throughout the process. The blank control group rats received no treatment.

[0049] Femoral artery hemostasis in SD rats: Rats were anesthetized and their leg hair was shaved. The inguinal muscles covering the groin were incised, and the artery and vein were dissected in a completely transverse manner. A pre-weighed gauze pad was placed around the wound. A commercially available sponge with a diameter of 5 mm and a height of 3 mm was injected into the bleeding cavity using a syringe. No additional force was applied, while the control group rats received no treatment. Hemostasis time and blood loss were recorded.

[0050] As attached Figure 1 As shown, (a) are scanning electron microscope images of four groups of sponges magnified at 100x and 1000x.

[0051] Low-magnification images show that all four sponge groups have interconnected porous structures. High-magnification images show that GMH is successfully loaded into the sponge interior, and with increasing loading amounts, more GMH is visible on the sponge surface. Conclusion: GMH loading does not disrupt the microporous structure of the sponge, and different GMH contents can be loaded as needed.

[0052] (b) Porosity results of the four groups of sponges

[0053] The porosity of the sponges in the GMH0 / SSP, GMH20 / SSP, and GMH50 / SSP groups remained above 80%, while the porosity of GMH100 / SSP decreased slightly. Conclusion: The sponge possesses a high-porosity structure, but excessively high GMH loading will reduce its porosity.

[0054] (c) PBS absorption volume-time curves of the four groups of sponges; (d) Rabbit blood absorption volume-time curves of the four groups of sponges.

[0055] The water / blood absorption capacity of the sponges in the GMH20 / SSP and GMH50 / SSP groups was comparable to that of the sponges without microgel loading. However, the liquid absorption performance decreased significantly with increasing GMH loading. Conclusion: Excessive GMH loading affects the sponge's porosity and surface properties, thus limiting its liquid absorption performance. To maintain high liquid absorption properties, the amount of GMH added needs to be controlled.

[0056] As attached Figure 2 As shown, (a) are four sets of images of the sponge in its initial state, compressed state, and expanded state under PBS and blood triggering. (b) are four sets of SEM images of the sponge in its initial state, compressed state, and expanded state under PBS triggering.

[0057] Due to its highly porous structure and stable mechanical strength, the dried sponge can be compressed. Upon contact with water or blood, water molecules enter the sponge's pores, triggering the sponge to return to its initial state and thus expand. As shown in the figure, all four groups of sponges exhibited an expansion effect upon contact with PBS or blood. This responsive expansion characteristic allows the sponge to fill the entire wound and exert a certain amount of pressure on the wound surface when treating irregular or deep wounds, helping the sponge adhere to the wound.

[0058] (c) PBS-triggered expansion time of the four groups of sponges. (d) Blood-triggered expansion time of the four groups of sponges.

[0059] The sponges in the GMH0 / SSP, GMH20 / SSP, and GMH50 / SSP groups recovered to their initial volume in a short time (<5s) regardless of whether they came into contact with PBS or blood, while the sponges in the GMH100 / SSP group had a longer recovery time.

[0060] As attached Figure 3 As shown, (a) are the uniaxial compressive stress-strain curves of the four groups of sponges.

[0061] (be) Four sets of stress-strain cycle (10 times) curves with sponge compressive strain of 80%.

[0062] (f) Maximum compressive stress of the four groups of sponges at 80% strain.

[0063] These results indicate that the mechanical strength of different sponges increases with the increase of microgel content, resulting in stronger filling effect and enhanced mechanical properties. Furthermore, the sponges exhibit high mechanical stability and show no significant mechanical loss after cyclic compression.

[0064] As attached Figure 4 As shown in the figure, the adhesion strength comparison data of the four groups of sponges is as follows. It can be seen from the figure that as the amount of microgel added increases, the amount of secondary cross-linking reaction that can be provided is higher, and the resulting adhesion force is also greater. Better adhesion strength allows the sponge to bond more firmly to the wound surface.

[0065] As attached Figure 5 As shown, (a) in vitro coagulation time for different groups. (b) in vitro coagulation index for different groups.

[0066] In terms of coagulation performance, the higher the loading of the microgel, the stronger its in vitro coagulation ability. This is related to the calcium silicate encapsulated in the microgel. The higher the loading, the faster the coagulation process can be accelerated and the stronger the thrombus can be formed.

[0067] (c) SEM images of platelet and erythrocyte adhesion in four groups of sponges.

[0068] As can be seen from the figure, the ability of microgels to adhere to blood components (platelets and red blood cells) increases with the increase of microgel loading, thereby further increasing the stability of thrombi.

[0069] As attached Figure 6 As shown, (a) is a diagram of the hemostasis process in the liver of SD rats for different groups of samples.

[0070] (b) Statistical results of hemorrhage in the liver of SD rats in different groups of samples.

[0071] (c) Images of different groups of samples after hemostasis in the liver of SD rats.

[0072] As shown in the figure, the sponge in the GMH50 / SSP group exhibited significantly improved hemostasis compared to the GMH0 / SSP group and commercially available gelatin sponges in the liver injury and bleeding model of SD rats. This is attributed to the adhesion mechanism introduced within the sponge and the loaded calcium silicate. Firstly, in this hemostasis experiment, no additional pressure was applied after the sponge was loaded; instead, it was allowed to adhere normally to the wound surface. Therefore, the hemostatic effect of the blank sponge and the commercially available sponge was relatively poor, relying solely on the wound's own coagulation process. However, the sponge in the GMH50 / SSP group, through adhesion, could quickly bind to the wound surface, forming a strong compressive force. Furthermore, the calcium silicate accelerated the coagulation process, reducing bleeding.

[0073] As attached Figure 7 As shown, (a) is a diagram of the hemostasis process of the sample in the femoral artery of an SD rat.

[0074] (b) Statistical results of hemostasis time in the liver of SD rats from different groups of samples.

[0075] (c) Statistical results of hemorrhage in the liver of SD rats in different groups of samples.

[0076] As can be seen from the figure, the sponge in the GMH50 / SSP group still exhibited superior hemostatic performance in the massive hemorrhage model. Rapidly flowing blood did not affect the chemical reactions of the adhesive components within the sponge.

[0077] Please note to all technical personnel: Although the present invention has been described according to the specific embodiments above, the inventive concept of the present invention is not limited to this invention. Any modifications that utilize the inventive concept will be included within the scope of patent protection of this patent.

[0078] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A highly adhesive porous sponge, characterized in that, The highly adhesive porous sponge is a modified starch sponge loaded with microgels. Calcium silicate is loaded onto the microgels. The microgels constitute 50% of the mass of the modified starch sponge in the highly adhesive porous sponge. The highly adhesive porous sponge is prepared through the following steps: S1. Preparation of modified starch porous sponge: Modified starch was dissolved in PBS containing PI 2959. At room temperature, HS-PEG-SH and Pranic were dissolved in PBS and mixed with the modified starch solution. After centrifugation and defoaming, carbon dioxide was used for pressurized foaming. The solution was released into a mold and allowed to stand. After being irradiated under ultraviolet light, the primary curing was completed. The cured material was freeze-dried to obtain modified starch sponge SSP. S2. Preparation of gelatin microgel: Gelatin and calcium silicate were dissolved in purified water to prepare an aqueous phase. Liquid paraffin containing 1% Span-80 was used as the oil phase. The volume ratio of the aqueous phase to the oil phase was 1:

20. Under water bath conditions, the aqueous gelatin solution was slowly added dropwise to the preheated oil phase to emulsify and form a uniform white emulsion. The entire system was rapidly cooled to 4°C and stirred continuously. After the process was completed, the lower gel solution was collected by low-temperature and low-speed centrifugation, which is the gelatin microgel GMH. S3. Preparation of adhesive gel: Gelatin microgels were dispersed in cold water at 4°C. Modified starch sponge SSP was immersed in the gelatin microgels. After vacuum extraction, it was washed with cold water, freeze-dried, and finally a highly adhesive porous sponge loaded with microgels was obtained.

2. The highly adhesive porous sponge according to claim 1, characterized in that, The modified starch in the modified starch sponge is norbornene-grafted starch St-Nor and oxidized starch OSt.

3. The highly adhesive porous sponge according to claim 1, characterized in that, The mass ratio of the microgel to its loaded calcium silicate is 10:

1.

4. A method for preparing the highly adhesive porous sponge according to claim 1, characterized in that, Includes the following steps: S1. Preparation of modified starch porous sponge: Modified starch was dissolved in PBS containing PI 2959. At room temperature, HS-PEG-SH and Pranic were dissolved in PBS and mixed with the modified starch solution. After centrifugation and defoaming, carbon dioxide was used for pressurized foaming. The solution was released into a mold and allowed to stand. After being irradiated under ultraviolet light, the primary curing was completed. The cured material was freeze-dried to obtain modified starch sponge SSP. S2. Preparation of gelatin microgel: Gelatin and calcium silicate were dissolved in purified water to prepare an aqueous phase. Liquid paraffin containing 1% Span-80 was used as the oil phase. The volume ratio of the aqueous phase to the oil phase was 1:

20. Under water bath conditions, the aqueous gelatin solution was slowly added dropwise to the preheated oil phase to emulsify and form a uniform white emulsion. The entire system was rapidly cooled to 4°C and stirred continuously. After the process was completed, the lower gel solution was collected by low-temperature and low-speed centrifugation, which is the gelatin microgel GMH. S3. Preparation of adhesive gel: Gelatin microgels were dispersed in cold water at 4°C. Modified starch sponge SSP was immersed in the gelatin microgels. After vacuum extraction, it was washed with cold water, freeze-dried, and finally a highly adhesive porous sponge loaded with microgels was obtained.

5. The preparation method according to claim 4, characterized in that, The modified starch is norbornene-grafted starch St-Nor and oxidized starch OSt, with a mass ratio of norbornene-grafted starch St-Nor to oxidized starch OSt of 3:

2.

6. The preparation method according to claim 4, characterized in that, In step S1, the concentration of PI 2959 is 0.1 wt%.

7. The preparation method according to claim 4, characterized in that, In step S1, the wavelength of the ultraviolet irradiation is 365 nm, and the power is 15 mW·cm. -2 .

8. The preparation method according to claim 4, characterized in that, In step S3, the microgel accounts for 50% of the mass percentage of the modified starch sponge.

9. The application of the highly adhesive porous sponge of claim 1 in the preparation of a moist wound hemostatic material.

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