A hemostatic composite material and its preparation method and application

Abstract

The present invention discloses a hemostatic composite material, its preparation method, and its application. The composite material comprises the following raw materials, by weight: hexamethylene diisocyanate, kaolin, an organosilicon surfactant, an inorganic base, a nonionic surfactant, and water. The hemostatic material, produced through the synergistic action of these raw materials, achieves rapid and effective hemostasis in rats with severe bleeding from peritoneal liver injury, femoral artery, vein, and nerve rupture.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical hemostatic materials, and in particular to a hemostatic composite material and a preparation method and application thereof. Background Art

[0002] Explosive fragments and gunshot wounds account for 75% of casualties in modern warfare, and hemorrhage remains the leading cause of death from battlefield trauma. Over 18% of these deaths could be prevented through effective hemostasis. Penetrating wounds, a severe form of trauma caused by a high-speed, sharp object penetrating human tissue, are common on the battlefield, in traffic accidents, and in violent incidents. Because penetrating wounds often rupture major blood vessels or damage vital organs, they trigger massive bleeding and carry a high mortality rate. Currently, the main emergency treatment methods for massive bleeding from penetrating wounds include direct compression, packing, and tourniquets. Tourniquets, which block blood flow to stop bleeding, are only suitable for severe bleeding and amputations of the limbs and lack a procoagulant effect. Current research recommends the use of tourniquets in appropriate locations, while newer hemostatic materials are recommended for bleeding in other locations. Combat Gauze and self-expanding polyurethane foam are the primary hemostatic materials used for packing penetrating wounds. Combat Gauze is a gauze containing a hemostatic agent that rapidly promotes clotting, but its effectiveness is limited for severe bleeding or deep wounds. Polyurethane foam hemostatic materials can rapidly expand within wounds, sealing the bleeding area and preventing blood from flowing out. However, these methods have certain problems in their application, such as incomplete hemostasis, complex operation, and the potential for secondary injury and infection. These methods are particularly limited when treating complex, multi-site penetrating wounds.

[0003] As a new type of hemostatic material, polyurethane foam hemostatic sponge has an in-situ polymerization process. The expansion rate and degree of the foam are difficult to precisely control, which may lead to excessive pressure on surrounding healthy tissue. The in-situ polymerization reaction process also generates high heat, and may even cause secondary injury. In addition, when facing massive arterial bleeding, simply using polyurethane foam sponge to stop bleeding is limited, resulting in poor hemostasis or the risk of secondary bleeding. At the same time, polyurethane materials may cause foreign body reactions and infection risks due to biodegradability issues.

[0004] Therefore, in order to meet the challenge of massive bleeding from penetrating wounds, it is urgent to design and develop safer hemostatic materials. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention provides a hemostatic composite material that, through the synthesis of raw materials, achieves rapid and effective hemostasis in rats with severe bleeding caused by abdominal liver injury, femoral artery, vein, and nerve rupture.

[0006] The present invention also provides a method for preparing the hemostatic composite material.

[0007] The present invention also proposes an application of the hemostatic composite material in preparing materials for treating hemorrhage caused by liver injury, femoral artery, vein and nerve rupture.

[0008] According to one aspect of the present invention, a hemostatic composite material is provided, which comprises the following raw materials in parts by weight: hexamethylene diisocyanate, kaolin, an organic silicon surfactant, an inorganic base, a nonionic surfactant and water.

[0009] In some embodiments of the present invention, the hemostatic composite material includes the following raw materials, by weight: 70-90 parts of hexamethylene diisocyanate, 1-20 parts of kaolin, 0.05-0.5 parts of silicone surfactant, 0.02-0.5 parts of inorganic base, 0.5-2 parts of nonionic surfactant and 10-30 parts of water.

[0010] The embodiments according to the first aspect of the present invention have at least the following beneficial effects:

[0011] 1. The raw materials used in the preparation of the hemostatic composite material of the present invention avoid the use of organic amines and organotin catalysts, resulting in high raw material safety. The hemostatic material prepared thereby meets the safety requirements of the blood system;

[0012] 2. In the present invention, by adding kaolin, the polyurethane foam sponge interface space formed by hexamethylene diisocyanate can absorb and retain blood components while initiating the chemical activation of the coagulation system, further rapidly amplifying the thrombin chain reaction, accelerating hemostasis, and stabilizing the thrombus.

[0013] 3. The pore structure of the hemostatic composite material of the present invention is uniform, and pores of uniform size can be formed through the synergistic effect of the non-ionic surfactant and other raw materials, and the process is simple.

[0014] 4. The hemostatic material obtained by the synergistic action of various component raw materials of the present invention, on the one hand, after the hemostatic sponge contacts the wound, immediately absorbs concentrated blood through the pore structure, enriches the red blood cells, platelets, coagulation-related factors and proteins in the concentrated blood, and rapidly amplifies the thrombin chain reaction rate; on the other hand, when the highly concentrated coagulation-related components contact the kaolin stably loaded on the interface of the hemostatic sponge, they can directly contact and activate FⅪ or FⅫ, accelerate the initiation of the intrinsic coagulation pathway, and further amplify the thrombin chain reaction rate; further, the specific pore structure can jointly construct a large thrombus network with the formed elements of the blood, thereby accelerating wound sealing.

[0015] In some embodiments of the present invention, the weight ratio of the hexamethylene diisocyanate, the silicone surfactant, the inorganic base, the nonionic surfactant and the water is 85-90:0.4-0.5:0.4-0.5:1-2:20-30.

[0016] The above ratio achieves uniformity of the mixture of the isocyanate prepolymer, kaolin and the organosilicon surfactant, as well as control of the pore structure of the material.

[0017] In some embodiments of the present invention, the organosilicon surfactant includes at least one of a polysiloxane surfactant, a silanol surfactant, a silane ester surfactant, a silane ether surfactant, and a silanol ester surfactant.

[0018] The above-mentioned silicone surfactants generally have good biocompatibility and can provide good wetting and emulsifying properties.

[0019] The addition of the above-mentioned organosilicon surfactant effectively improves the dispersibility of the isocyanate prepolymer and the inorganic salt in the system.

[0020] In some embodiments of the present invention, the nonionic surfactant includes at least one of a polyoxyethylene-polyoxypropylene block copolymer, a fatty alcohol polyoxyethylene ether, and an alkylphenol polyoxyethylene ether.

[0021] The above nonionic surfactants synergistically exhibit good wettability and stability in the system with other components, can effectively adjust the microstructure of the polyurethane foam, and promote the cell opening effect of the foam.

[0022] In some embodiments of the present invention, the inorganic base includes at least one of sodium bicarbonate, sodium carbonate, potassium carbonate and potassium bicarbonate.

[0023] The inorganic base provides an alkaline environment and acts as a catalyst, increasing the reaction rate of the system. This helps regulate the structure of the hemostatic composite material, resulting in uniform pores and improving the biosafety of the material. Hexamethylene diisocyanate has low reactivity, resulting in low foaming efficiency at room temperature and prone to product shrinkage. However, the catalyst improves its foaming efficiency.

[0024] In some embodiments of the present invention, the particle size of the kaolin is 1 to 10 μm.

[0025] Kaolin with the above particle size can prevent particle sedimentation and improve the uniformity and stability of the system.

[0026] A second aspect of the present invention provides a method for preparing a hemostatic composite material, comprising the following steps:

[0027] S1. The polyurethane prepolymer, kaolin and silicone surfactant were mixed to obtain liquid A, and the inorganic base, water, and 0.5 nonionic surfactant were heated and mixed to obtain liquid B;

[0028] S2. Liquid A and Liquid B are mixed and coated on a silicone release paper, foamed, and cured, and then the release paper is removed to obtain a hemostatic composite material.

[0029] The hemostatic composite material proposed in the present invention is synthesized through a two-step process of raw material compounding. This improves the biocompatibility of polyurethane foam materials and avoids yellowing and core burning caused by rapid material heating. This hemostatic material, with a controllable pore structure and a stable organic-inorganic composite, is suitable for emergency hemostasis treatment of severe bleeding, particularly in situations such as penetrating abdominal wounds and groin hemorrhage. Upon contact with the wound, the hemostatic sponge immediately absorbs concentrated blood through its pore structure, enriching the concentrated blood with red blood cells, platelets, coagulation-related factors, and proteins, rapidly amplifying the rate of the thrombin chain reaction. Furthermore, when the highly concentrated coagulation-related components come into contact with the kaolin stably loaded on the hemostatic sponge's interface, they directly contact and activate FXI or FXII, accelerating the initiation of the intrinsic coagulation pathway and further amplifying the rate of the thrombin chain reaction. Furthermore, the specific pore structure can form a large thrombus network with formed blood components, accelerating wound closure.

[0030] In some embodiments of the present invention, in step S2, the parameters of the mixing step are: mixing at 1000-5000 r / min for 5-15 s.

[0031] In some embodiments of the present invention, in step S2, the temperature of the foaming step is not higher than 60°C.

[0032] The reaction temperature is less than 60℃ to ensure uniform pores of the material.

[0033] In some embodiments of the present invention, in step S2, the curing parameters are: curing at 25° C. to 60° C. for 10 to 30 minutes.

[0034] In the present invention, during the polymerization process of the polyurethane foam, the pore structure and size can be controlled by adjusting the formula (such as isocyanate prepolymer and water, silicone surfactant, nonionic surfactant), raw material pre-cooling temperature, reaction temperature, and stirring rate to affect the bubble generation, expansion and stability of the foam, thereby controlling its final pore size and structure.

[0035] In some embodiments of the present invention, the silicone release paper includes polysilicone release paper.

[0036] The present invention adopts polysilicone release paper to effectively prevent adhesion to the hemostatic composite material, thereby avoiding bottom closure and ensuring the integrity and controllability of the pore structure.

[0037] The third aspect of the present invention provides a use of the hemostatic composite material in preparing materials for treating hemorrhage caused by liver injury, femoral artery, vein and nerve rupture.

[0038] In some embodiments of the invention, the material comprises a hemostatic sponge. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0040] Figure 1 This is the appearance diagram of the composite hemostatic material;

[0041] Figure 2 This is a scanning electron microscope image of the bottom of the composite hemostatic material;

[0042] Figure 3 This is a scanning electron microscope image of the cross section of the composite hemostatic material;

[0043] Figure 4 The hemostatic effect of composite hemostatic material on the severed femoral artery, vein and nerve of SD rats;

[0044] Figure 5 The liquid blocking performance of the composite hemostatic material;

[0045] Figure 6 Activation of the coagulation system by composite hemostatic materials;

[0046] Figure 7 The adhesion of the composite hemostatic material to blood cells;

[0047] Figure 8 The stability of kaolin powder in solution of composite hemostatic material;

[0048] Figure 9 Blood compatibility of composite hemostatic materials;

[0049] Figure 10 The cytotoxicity of the composite hemostatic material. DETAILED DESCRIPTION

[0050] The following will clearly and completely describe the concept and technical effects of the present invention in conjunction with the embodiments to fully understand the purpose, features and effects of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0051] In the embodiment, the silane ether surfactant is Dowsil 556, the silanol ester surfactant is SilresBS 94, the silane ester surfactant is Geniosil STP-E, and the silanol surfactant is BS 605, polysiloxane surfactants are BS100;

[0052] Polyoxyethylene-polyoxypropylene-polyoxyethylene is BASF Pluronic PE (BASF);

[0053] The fatty alcohol polyoxyethylene ether is AEO-9;

[0054] The alkylphenol polyoxyethylene ether is OP-10.

[0055] Example 1

[0056] This embodiment provides a method for preparing a hemostatic composite material, specifically:

[0057] S1. 70 parts of HDI polyurethane prepolymer (Baymedix FP504), 1 part of kaolin and 0.05 parts of silanol surfactant BS 605 was quickly mixed to obtain liquid A; then 0.02 parts of sodium bicarbonate, 10 parts of deionized water, and 0.5 parts of PEO-PPO-PEO pore opener (BASF Pluronic PE) were heated and mixed to obtain liquid B;

[0058] S2. Mix liquid A and liquid B at 1500 r / min for 15 seconds, pour the mixture onto a silicone release paper, smooth it with a scraper, foam it at room temperature, and cure it at 40°C for 30 minutes. Remove the release paper to obtain hemostatic composite material 1.

[0059] The appearance of the hemostatic composite material is shown in the figure Figure 1 shown.

[0060] Example 2

[0061] This embodiment provides a method for preparing a hemostatic composite material, specifically:

[0062] S1. 80 parts of HDI polyurethane prepolymer, 10 parts of kaolin and 0.2 parts of polysiloxane surfactant BS100 was quickly mixed to obtain liquid A; then 0.2 parts of sodium carbonate, 20 parts of deionized water, and 1 part of PEO-PPO-PEO pore opener were heated and mixed evenly to obtain liquid B;

[0063] S2. Mix liquid A and liquid B at 2000 r / min for 10 seconds. Pour the mixture onto a silicone release paper and smooth it with a spatula. Foam at room temperature and cure at 40°C for 20 minutes. Remove the release paper to obtain composite hemostatic material 2.

[0064] Example 3

[0065] This embodiment provides a method for preparing a hemostatic composite material, specifically:

[0066] S1. 90 parts of HDI polyurethane prepolymer, 20 parts of kaolin and 0.5 parts of silane ester surfactant Geniosil STP-E were quickly mixed to obtain liquid A; 0.5 parts of potassium carbonate, 30 parts of deionized water, and 2 parts of PEO-PPO-PEO pore opening agent were heated and mixed to obtain liquid B;

[0067] S2. Mix liquid A and liquid B at 5000 r / min for 5 seconds. Pour the mixture onto a silicone release paper and smooth it with a spatula. Foam at room temperature and cure at 60°C for 10 minutes. Remove the release paper to obtain composite hemostatic material 3.

[0068] Example 4

[0069] This embodiment provides a method for preparing a hemostatic composite material, specifically:

[0070] S1. 90 parts of HDI polyurethane prepolymer, 20 parts of kaolin and 0.5 parts of silanol surfactant BS 605 was quickly mixed to obtain liquid A; then 0.5 parts of potassium bicarbonate, 30 parts of deionized water, and 2 parts of PEO-PPO-PEO pore opener were heated and mixed to obtain liquid B;

[0071] S2. Mix liquid A and liquid B at 5000 r / min for 5 seconds, pour the mixture onto a silicone release paper, smooth it with a scraper, foam it at room temperature, and cure it at 40°C for 20 minutes. Remove the release paper to obtain hemostatic composite material 4.

[0072] Example 5

[0073] This embodiment provides a method for preparing a hemostatic composite material, specifically:

[0074] S1. 90 parts of HDI polyurethane prepolymer, 20 parts of kaolin and 0.5 parts of silanol surfactant BS 605 was quickly mixed to obtain liquid A; then 0.5 parts of sodium bicarbonate, 30 parts of deionized water, and 2 parts of PEO-PPO-PEO pore opener were heated and mixed to obtain liquid B;

[0075] S2. Mix liquid A and liquid B at 2000 r / min for 5 seconds, pour the mixture onto a silicone release paper, smooth it with a scraper, foam it at room temperature, and cure it at 25°C for 20 minutes. Remove the release paper to obtain the hemostatic composite material 5 (20PK).

[0076] Example 6

[0077] This embodiment provides a method for preparing a hemostatic composite material, specifically:

[0078] S1. 90 parts of HDI polyurethane prepolymer, 5 parts of kaolin and 0.5 parts of silanol surfactant BS 605 was quickly mixed to obtain liquid A; then 0.5 parts of sodium bicarbonate, 30 parts of deionized water, and 2 parts of PEO-PPO-PEO pore opener were heated and mixed to obtain liquid B;

[0079] S2. Mix liquid A and liquid B at 5000 r / min for 5 seconds, pour the mixture onto a silicone release paper, scrape it flat with a scraper, foam it at room temperature, and cure it at 25°C for 20 minutes. Remove the release paper to obtain a hemostatic composite material 6 (5PK). Figure 2 and Figure 3 It can be seen that the pores of the hemostatic sponge are clear, without collapse, and the pore diameter is 50-200 μm.

[0080] Comparison of the SEM images of 5PK and 20PK shows that this preparation method can still maintain a stable pore structure as the amount of kaolin increases.

[0081] Example 7

[0082] This embodiment provides a method for preparing a hemostatic composite material, specifically:

[0083] S1. 90 parts of HDI polyurethane prepolymer, 10 parts of kaolin and 0.5 parts of silanol surfactant BS 605 was quickly mixed to obtain liquid A; then 0.5 parts of sodium bicarbonate, 30 parts of deionized water, and 2 parts of PEO-PPO-PEO pore opener were heated and mixed to obtain liquid B;

[0084] S2. Mix liquid A and liquid B at 5000 r / min for 5 seconds, pour the mixture onto silicone release paper, scrape it flat with a scraper, foam it at room temperature, and cure it at 25°C for 20 minutes. Remove the release paper to obtain material 7 (10PK). Figure 2 and Figure 3 It can be seen that the pores of the hemostatic sponge are clear, without collapse, and the pore diameter is 50-200 μm.

[0085] Example 8

[0086] This embodiment provides a method for preparing a hemostatic composite material, specifically:

[0087] S1. 90 parts of HDI polyurethane prepolymer, 15 parts of kaolin and 0.5 parts of silanol surfactant BS 605 was quickly mixed to obtain liquid A; then 0.5 parts of sodium bicarbonate, 30 parts of deionized water, and 2 parts of PEO-PPO-PEO pore opener were heated and mixed to obtain liquid B;

[0088] S2. Mix liquid A and liquid B at 5000 r / min for 5 seconds, pour the mixture onto a silicone release paper, scrape it flat with a scraper, foam it at room temperature, and cure it at 25°C for 20 minutes. Remove the release paper to obtain a hemostatic composite material 8 (15PK). Figure 2 and Figure 3 It can be seen that the pores of the hemostatic sponge are clear, without collapse, and the pore diameter is 50-200 μm.

[0089] Comparative Example 1

[0090] This comparative example provides a method for preparing a hemostatic composite material. The difference between this comparative example and the embodiment is that a TDI-type polyurethane prepolymer is used, specifically:

[0091] S1. 90 parts of TDI polyurethane prepolymer, 20 parts of kaolin and 0.5 parts of silicone surfactant were quickly mixed to obtain liquid A; 0.5 parts of sodium bicarbonate, 30 parts of deionized water, and 2 parts of PEO-PPO-PEO pore opening agent were heated and mixed to obtain liquid B;

[0092] S2. Mix liquids A and B at 5000 r / min for 5 seconds. Pour the mixture onto a silicone release paper and smooth it with a spatula. Foam and cure at room temperature for 20 minutes. Remove the release paper to obtain material C1.

[0093] Compared to Example C1, the foam is yellowish and hard, making it unsuitable for use as a hemostatic composite material. PU foam starting with TDI is prone to yellowing due to the presence of the benzene ring. The large π bond on the benzene ring forms a conjugated bond with the adjacent NCO. Exposure to light, heat, oxygen, and especially ultraviolet light, causes the urethane bond to decompose, forming aromatic amines. The benzene nuclei on the aromatic amines undergo oxidative rearrangement, forming chromophores such as quinone structures. As a result, the resulting PU product easily yellows and cannot maintain a water-white color for long periods of time.

[0094] Comparative Example 2

[0095] This comparative example provides a method for preparing a hemostatic composite material. The difference between this comparative example and the example is that montmorillonite is used instead of the kaolin in the example, and the other conditions are the same.

[0096] Compared with the embodiment, the hemostatic composite material has poor biocompatibility and is prone to cause distal embolism, and is not suitable as a hemostatic composite material.

[0097] Comparative Example 3

[0098] This comparative example provides a method for preparing a hemostatic composite material. The difference between this comparative example and the example is that triethylamine is used instead of the sodium bicarbonate in the example, and the other conditions are the same.

[0099] Compared with the examples, the organic amine catalyst in the hemostatic composite material is irritating to the eyes and skin, and the hemostatic composite material prepared with the organic amine catalyst results in uneven pores and is therefore not suitable as a hemostatic composite material.

[0100] Test Example 1

[0101] This test investigated the effects of different materials on hemostasis following severed liver, femoral artery, vein, and nerve in Sprague-Dawley rats. Male Sprague-Dawley rats weighing approximately 400 g were randomly divided into a gauze group (blank control), a combat gauze group, and a material group, with four rats in each group.

[0102] (1) SD rat liver hemostasis experiment The hemostatic properties of the material were evaluated using a liver injury model. The material was sterilized with UV one day before the operation. The SD rats were anesthetized using a small animal gas anesthesia machine and isoflurane. The rats were placed in a supine position to expose their abdomens. The abdomens of the rats were opened with surgical scissors to expose one lobe of the liver. The liver was rinsed with a small amount of saline and the excess fluid was wiped off with gauze. The filter paper was placed under the liver, and a cross incision (1.5 cm × 1.5 cm) was made in the liver tissue with a scalpel. The material was then immediately laid on top and a timer was used to count down for 6 minutes. After the end, the amount of blood loss was recorded and photographed. After the experiment was completed, the SD rats were euthanized. As shown in Table 1, with the increase of kaolin, the bleeding caused by liver injury was significantly reduced, and PK20 was significantly better than the positive control group.

[0103] Table 1. Effects of Examples and Comparative Examples on Hemostasis of Liver and Femoral Artery, Vein and Nerve in SD Rat

[0104]

[0105] (2) Hemostasis experiment of femoral artery, vein and nerve severance in SD rats

[0106] The hemostatic ability of the material for massive bleeding was evaluated by the groin hemorrhage model. The material was sterilized with ultraviolet light the day before the operation. SD rats were general anesthetized using a small animal gas anesthesia machine and isoflurane, and the rats were placed in a supine position. Depilation was performed around the left lower limb. After disinfection, the skin of the left lower limb of the SD rat was cut open with surgical scissors to expose the groin area as much as possible. The femoral artery, vein and nerve at the root of the groin of the left leg of the SD rat were cut open simultaneously using a scalpel, the material was immediately paved, and a 100g weight was placed above the material for 30s (simulated compression hemostasis). After 10min, the amount of blood loss was recorded and photographed for record. After the experiment was completed, the SD rats were euthanized. The results are shown in Table 2.

[0107] Table 2. Hemostasis experiment of femoral artery, vein and nerve severance in SD rats

[0108]

[0109]

[0110] Test Example 2

[0111] This test case tests the effect of different materials on water contact angle to verify that the polyurethane kaolin composite hemostatic sponge has spatial blocking and micro-expansion effects on liquids. The water contact angle of the sample is measured using a contact angle meter, and photos are taken to record and observe the shape changes of the droplet and the material. Figure 5 It can be seen that with the addition of kaolin, the hydrophobicity of the interface of the polyurethane foam sponge gradually increases within a few seconds. It is based on this change in properties that when blood comes into contact with the hemostatic composite sponge, the sponge has a spatial barrier effect on the microenvironment of the blood, especially its formed components ( Figure 6 ), a large number of blood cells adhere and aggregate at the interface ( Figure 6 ), which significantly reduces the amount of bleeding in major hemorrhage (Tables 1 and 2) and enables faster thrombus formation ( Figure 4 As shown in Table 2, with the increase of kaolin, the bleeding of femoral artery, vein and nerve was significantly reduced, and PK20 was significantly better than the positive control group.

[0112] Test Example 3

[0113] This test case examined the effects of different materials on blood cell adhesion.

[0114] Collect blood from the New Zealand rabbit's ear vein in a sodium citrate anticoagulation tube. Mix 8 mL of fresh anticoagulated New Zealand rabbit's ear vein blood with 10 mL of normal saline in a container to obtain diluted blood. Cut the material into 1.5 cm × 1.5 cm squares in a 12-well plate and divide it into two groups for processing. Incubate in a 37°C shaker for 10 minutes, then add 500 μL of fresh anticoagulated blood and 500 μL of the aforementioned diluted blood to the top of the sample. Continue to incubate in a 37°C shaker for 5 minutes, then wash three times with phosphate-buffered saline (PBS) to remove free blood cells, and fix overnight with 2.5% glutaraldehyde. After fixation, the excess glutaraldehyde solution was removed and the samples were dehydrated in a series of gradient ethanol concentrations, including 30%, 50%, 70%, 90%, and 100% ethanol. Each dehydration lasted for 15 minutes. The samples were allowed to dry naturally and then gold-sprayed. The cell adhesion status on the surface of the material was observed using a scanning electron microscope (SEM). Figure 6 It can be seen that compared with Figure 6 a) pure polyurethane foam material, Figure 6 The pore structure of the 20PK hemostatic sponge in b) allows for the aggregation and adhesion of a larger number of blood cells. This further demonstrates that the steric barrier and capillary action of the hemostatic sponge help blood components to remain at the sponge interface, allowing for stronger adhesion and aggregation, thereby contributing to the formation of a more stable thrombus and preventing secondary bleeding.

[0115] Test Example 4

[0116] This test case tests the effects of different materials on the activation of endogenous and exogenous coagulation pathways (APTT and PT) through chemical reactions. After the sample is sterilized by UV, 0.5 g of material and 10 mL of PBS are added to a centrifuge tube and placed in a 37°C constant temperature shaker for 24 hours. The material is discarded to obtain an extract. (1) Activated partial thromboplastin time (APTT) test: The APTT reagent and CaCl2 solution in the kit are placed in the 37°C preheating tank of the coagulation analyzer and preheated for more than 5 minutes and less than 15 minutes. 50 μL of extract, 50 μL of plasma, and 50 μL of APTT reagent (preheated) are sequentially aspirated into the sample cup, and magnetic beads are added. The sample is incubated at 37°C for 5 minutes. Afterwards, 100 μL of CaCl2 solution (preheated) is added and the coagulation analyzer is triggered to measure and obtain the measurement results. (2) Prothrombin time (PT) test: Place the PT reagent in the 37°C preheating tank of the coagulation analyzer and preheat for 5 minutes to 15 minutes. Pipette 50 μL of extract and 50 μL of plasma into the sample cup, add magnetic beads, and incubate at 37°C for 3 minutes. Then, add 100 μL of PT reagent (preheated) and trigger the coagulation analyzer to measure and obtain the measurement results.

[0117] APTT (activated partial thromboplastin time) is a screening indicator for the intrinsic coagulation pathway, and PT (plasma prothrombin time) is a screening indicator for the extrinsic coagulation pathway. Figure 7 The results show that the addition of kaolin activates the intrinsic coagulation pathway and accelerates plasma coagulation, and within the dosage range of the present invention, the plasma coagulation becomes faster as the amount of kaolin added increases.

[0118] Test Example 5

[0119] This test case tests the effect of different materials on the stability of kaolin powder in aqueous solution. The material was soaked in phosphate buffer solution (PBS) at a ratio of 0.3g / 10mL and placed in a 37℃ constant temperature shaking box. Photos were taken at 0h and 24h for comparison to observe whether there was any precipitation in the liquid. Figure 8 It can be seen that compared with the reference product CombatGauze, the loading stability of kaolin is greatly improved after the prepolymer and kaolin are evenly mixed and polymerized, which can effectively prevent kaolin from entering the human blood system through the blood circulation, effectively avoid the occurrence of distal embolism, and have better biosafety.

[0120] Test Example 6

[0121] This test case examined the effect of different materials on blood compatibility.

[0122] According to the YY / T 1651.1-2019 standard, the material was tested for hemolysis. 8 mL of fresh anticoagulated New Zealand rabbit ear vein blood was mixed with 10 mL of normal saline in a container and mixed thoroughly to prepare diluted blood. The test was performed using the indirect contact method. Due to the strong water absorption of the material, the extract was prepared at a ratio of 0.03 g / mL of material to extraction medium, that is, 0.3 g of material was added to 10 mL of normal saline, and then placed in a shaker at 37°C for (72±2) hours to ensure that the extract was fully mixed. 2 mL of the extract was transferred to a new centrifuge tube for use, and 3 parallel samples were prepared at the same time. 2 mL of normal saline was added to another centrifuge tube as a control. 2 mL of normal saline and 5 mL of distilled water were added to the tubes of the negative and positive control groups, respectively, and 3 parallel samples were prepared at the same time. Place these centrifuge tubes in a 37°C 100 rpm constant temperature shaker and incubate for 0.5 h. Then, add diluted blood to each centrifuge tube at a ratio of 0.2 mL diluted blood / 10 mL normal saline, mix gently, and then incubate in a 37°C 100 rpm constant temperature shaker for 1 h. Finally, centrifuge at low temperature (800 g, 5 min). Pipette 100 μL of supernatant into a 96-well plate and measure the absorbance at a wavelength of 545 nm using an enzyme reader. Calculate the hemolysis rate (HI) according to formula (3-3). Figure 9It can be seen that the prepared polyurethane foam kaolin composite hemostatic sponges meet the national standard requirement for hemolysis rate (≤5%) and have excellent blood compatibility.

[0123] Test Example 7

[0124] This test case tests the effect of different materials on cytotoxicity.

[0125] After the material is sterilized by ultraviolet, it is soaked in a ratio of 0.3g material / 10mL culture medium, placed in a constant temperature shaker at 37°C for 24 hours, the material is discarded, and then filtered with a 0.22μm filter to obtain an extract. The culture medium used for L929 cell culture is α-MEM culture medium containing 1% double antibody and 10% fetal bovine serum. L929 cells are seeded in a 96-well plate at a rate of 5000 cells per well. After 24 hours, the cells are allowed to adhere to the wall, the culture medium is aspirated, and the culture medium to be tested is added, and the plate is placed in an incubator for culture for 24 hours. Remove the upper culture medium, add CCK-8 reagent under light-proof conditions, and incubate in the dark for half an hour. Use an enzyme reader to measure the absorbance at a wavelength of 450nm. By Figure 10 It can be seen that the prepared polyurethane foam kaolin composite sponges meet the national standard requirements for cytotoxicity (cell survival rate ≥ 75%) and have excellent cell safety.

Claims

1. A hemostatic composite material, characterized in that: The hemostatic composite material comprises the following raw materials, in parts by weight: 70-90 parts of hexamethylene diisocyanate, 1-20 parts of kaolin, 0.05-0.5 parts of an organic silicon surfactant, 0.02-0.5 parts of an inorganic base, 0.5-2 parts of a nonionic surfactant, and 10-30 parts of water; The organosilicon surfactant comprises at least one of a polysiloxane surfactant, a silanol surfactant, a silane ester surfactant, a silane ether surfactant and a silanol ester surfactant; The nonionic surfactant comprises at least one of a polyoxyethylene-polyoxypropylene block copolymer, a fatty alcohol polyoxyethylene ether and an alkylphenol polyoxyethylene ether; The inorganic base includes at least one of sodium bicarbonate, sodium carbonate and potassium carbonate; The preparation method of the hemostatic composite material comprises the following steps: S1. The HDI polyurethane prepolymer, kaolin and silicone surfactant were mixed to obtain liquid A, and the inorganic base, water and nonionic surfactant were heated and mixed to obtain liquid B; S2. Liquid A and Liquid B are mixed and coated on a silicone release paper, foamed, and cured, and then the release paper is removed to obtain a hemostatic composite material.

2. The hemostatic composite material according to claim 1, characterized in that: By weight ratio, the hexamethylene diisocyanate, the silicone surfactant, the inorganic base, the nonionic surfactant and the water are 85-90:0.4-0.5:0.4-0.5:1-2:20-30.

3. The hemostatic composite material according to claim 1, characterized in that: The particle size of the kaolin is 1-10 μm.

4. The hemostatic composite material according to claim 1, characterized in that: The organic silicone release paper includes polysilicone release paper.

5. Use of the hemostatic composite material according to any one of claims 1 to 4 in preparing a material for treating hemorrhage caused by liver injury, femoral artery, vein and nerve rupture.

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