A highly expandable hemostatic material and its preparation method

Abstract

The present invention relates to a highly expandable hemostatic material, which comprises 10 - 50 parts of polyvinyl alcohol and 0.5 - 10 parts of modified polysaccharide, wherein the modified polysaccharide is selected from one or more of sodium carboxymethyl cellulose and carboxymethyl chitosan. The present invention also relates to a preparation method of the hemostatic material. The hemostatic material of the present invention has better expansibility and water absorbency, and at the same time has a better hemostatic effect, has good biocompatibility, can be used for first aid hemostasis, especially for bleeding caused by large artery and vein injuries, and can also be used for tamponade hemostasis of bleeding in a confined space, such as nosebleed and ballistic wound hemostasis.

Description

Technical Field

[0001] The present invention belongs to the field of medical hemostatic materials, and more particularly relates to a highly expandable hemostatic material, and also relates to a preparation method of the highly expandable hemostatic material. Background Art

[0002] Bleeding injuries mainly include two types: 1) Compressible bleeding wounds, such as external capillary, venous, and arterial bleeding; 2) Incompressible wounds, such as subdermal or internal venous and arterial bleeding. The most common hemostatic method is to cover the wound with a bandage and then directly apply pressure to promote thrombus formation. Traumatic bleeding is one of the most common injuries at the battlefield and various accident scenes. Among them, uncontrollable massive bleeding is the main cause of death in war injuries, and the proportion of death due to blood loss is as high as 50%. In particular, excessive blood loss within 5 - 10 minutes after injury is an important factor leading to death. The analysis of battlefield deaths of the US military from 2001 to 2011 found that 24% of pre-hospital deaths were "survivable" deaths, and among the "survivable" death casualties, 90.9% died of bleeding. Therefore, pre-hospital traumatic hemostasis is crucial.

[0003] Currently, existing hemostatic materials are mainly divided into several types, such as hemostatic powders (e.g., QuickClot), hemostatic gauzes, bandages (e.g., HemCon, Celox, etc.), hemostatic sponges, hemostatic dressings, etc. Although clinical applications have shown that hemostatic powders can effectively stop bleeding, since their main components are minerals, most of them cannot be biodegradable, and it is necessary to remove the residual hemostatic materials. Moreover, there may be a secondary injury situation where the wound is burned due to heat release. Most of the current hemostatic sponge products achieve the hemostatic effect mainly through a single physical expansion and compression hemostasis effect (such as: liquid absorption and expansion packing hemostasis, pressing hemostasis, etc.). However, there are also some problems. For example, gelatin-based products may cause some allergic reactions during clinical use, and the hemostatic effect is not good. Also, when treating massive bleeding, simply stopping bleeding by packing and blocking is unable to stop bleeding in a timely and effective manner. In cases where rapid hemostasis is required, on the one hand, the hemostatic material needs to have good liquid absorption performance to rapidly expand and block the wound, and on the other hand, it needs to rapidly absorb the water in the blood to achieve rapid blood coagulation. In the outdoors or on some battlefields, if no further treatment is carried out after hemostasis, the wound is prone to infection, which is not conducive to wound healing. The current gelatin hemostatic sponges and PVA hemostatic sponges only complete the hemostatic function singly, and the expansion performance is limited. Polysaccharide-based hemostatic materials have good biocompatibility and biodegradability, and have a certain antibacterial effect. However, the mechanical strength of polysaccharide-based hemostatic materials is often poor and cannot be effectively used to control bleeding from high-pressure arterial wounds and abdominal cavity wounds, etc. Hemostatic dressings are often used for some superficial wounds and are suitable for small wounds, but they have poor hemostatic effects and are not applicable to large wounds or penetrating wounds, etc. Most of the existing hemostatic products usually cannot be placed into the narrow cavities of the injured, nor do they conform to the irregular tissue morphology of the wound, and most of them have a single efficacy. There may be a risk of bacterial infection in many wounds during the hemostasis process.

[0004] In summary, it is still necessary to develop a high-expansion antibacterial hemostatic material with a better hemostatic effect. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a high-expansion antibacterial hemostatic material capable of rapidly stopping bleeding and a preparation method thereof.

[0006] In the first aspect of the present invention, a highly expandable hemostatic material is provided, which is characterized in that, by weight parts, the highly expandable hemostatic material comprises 10-50 parts of polyvinyl alcohol and 0.5-10 parts of modified polysaccharide, wherein the modified polysaccharide is a mixture of sodium carboxymethyl cellulose and carboxymethyl chitosan, and the mass ratio range of sodium carboxymethyl cellulose to carboxymethyl chitosan is 2.9-0.1:0.1-2.9. Preferably, the mass ratio range of sodium carboxymethyl cellulose to carboxymethyl chitosan is 1.5-2.5:2.5-1.5. In a specific embodiment, the mass ratio of sodium carboxymethyl cellulose to carboxymethyl chitosan is 2:1. The inventors unexpectedly found that the mass ratio of sodium carboxymethyl cellulose to carboxymethyl chitosan has an impact on the water absorption performance, expansion performance and coagulation performance of the material, and through a large number of experiments, the optimal mass ratio range of sodium carboxymethyl cellulose to carboxymethyl chitosan applied to the hemostatic material of the present invention was found, so that the hemostatic material of the present invention achieves the best physical properties and hemostatic effect.

[0007] Optionally, the degree of alcoholysis of the polyvinyl alcohol is 77%-99%. Polyvinyl alcohol (PVA) sponge is a swellable medical material, which is mostly used for the treatment, nursing of body surface wounds, the treatment of otolaryngology and closed negative pressure drainage. The PVA sponge itself does not have a hemostatic function, and mainly relies on its rapid blood absorption and swelling locally to produce a physical compression effect for hemostasis.

[0008] Optionally, by weight parts, the hemostatic material further comprises 0.1-10 parts of an antibacterial component, and the antibacterial component comprises honey; preferably, the honey is 0.1-5 parts, and more preferably, the honey is 0.15-0.5 parts. At the same time, substances such as Ag + and antibacterial peptides can be considered for compounding.

[0009] The honey in the antibacterial component can provide good conditions for wound healing: First, it contains 70%-80% sugar, which can create a hypertonic environment. This hypertonic environment can not only absorb deep body fluids to keep the wound surface moist and absorb the water in inflammatory cells to eliminate wound surface edema, thereby protecting the wound surface; it can also dehydrate bacteria to death, achieving the purpose of inhibiting bacterial growth. Secondly, honey also contains rich nutrients, such as glucose, invert sugar, invertase and various vitamins, trace elements, amino acids, etc. Once these nutrients are utilized by tissue cells, it is beneficial to accelerate wound healing. The inventors found that the addition of honey can not only play a good antibacterial effect on the wound surface during the first-aid hemostasis process, but also further cooperate with other materials to improve the hemostatic effect of the hemostatic material.

[0010] In the second aspect of the present invention, a preparation method of the above-mentioned hemostatic material is provided, which is characterized in that it comprises the following steps:

[0011] (1) Dissolve the polyvinyl alcohol in water to obtain an aqueous polyvinyl alcohol solution; preferably, dissolve the polyvinyl alcohol in water at 80 - 90 °C;

[0012] (2) Dissolve the modified polysaccharide in a calcium salt solution for complexation to obtain a first network solution; preferably, the calcium salt is selected from any one of calcium chloride, calcium oxalate, and calcium sulfate; preferably,

[0013] Add an antibacterial component to the first network solution;

[0014] (3) Mix the aqueous polyvinyl alcohol solution obtained in step (1) with the first network solution to obtain a blend solution, add a catalyst and a crosslinking agent for crosslinking reaction to obtain a second network solution; preferably, the catalyst is an inorganic acid, and the crosslinking agent is selected from one or more of formaldehyde, acetaldehyde, glutaraldehyde, and hexanedial;

[0015] (4) After the crosslinking reaction in step (3) is completed, add a pore-forming agent and stir for 1 - 5 h; preferably, the pore-forming agent is starch or carbonate; in a specific embodiment, the pore-forming agent used is NaHCO3;

[0016] (5) After step (4) is completed, cure the product at 50 - 80 °C for 5 - 24 h; preferably, after curing, wash the product with water until it is neutral;

[0017] (6) Put the product obtained in step (5) into a freeze dryer for freeze-drying to obtain the product.

[0018] Steps (1) and (2) in the above steps can be carried out in any order, either successively or simultaneously, without being restricted by the order of the serial numbers.

[0019] Optionally, the calcium salt solution in step (2) is a 2 mass% - 10 mass% calcium salt solution.

[0020] In the present invention, after the modified polysaccharide is complexed and crosslinked with Ca 2+ to form a calcium-based polysaccharide material, after the addition of Ca 2+ for modification, it can promote the hemostatic effect of the polysaccharide material; at the same time, since the modified polysaccharide material can form a spatial network structure by complexing with Ca 2+ , it can further enhance the hemostatic effect and mechanical strength of the polysaccharide material. Using other metal ions cannot achieve the effects of the present invention.

[0021] Optionally, the crosslinking reaction conditions in step (3) are heating in a water bath at 30 - 60 °C and crosslinking for 1 - 5 h under mechanical stirring at 200 - 2500 rpm.

[0022] Optionally, in step (3), based on the blend solution, the crosslinking agent content is 0.05% to 5% by mass; the pore-forming agent content is 15% to 60% by mass; the catalyst content is 0.05% to 5% by mass. The types and contents of the crosslinking agent, pore-forming agent, and catalyst used in the preparation method of the present invention are all selected based on the reaction yield and the properties of the obtained product, which can ensure excellent reaction products with high yield, superior to the effects of methods outside the scope limited by the present invention.

[0023] Through the above preparation method, the above components can be crosslinked hierarchically to form a multiple three-dimensional network structure. The first network structure formed by the calcium salt and the modified polysaccharide and the second interpenetrating network structure formed by polyvinyl alcohol through a specific catalyst and crosslinking agent can improve the hemostatic performance and adsorption performance of the product while enhancing the mechanical properties, enabling rapid hemostasis and antibacterial properties, and can be applied to stop bleeding from irregular penetrating wounds that cannot be deeply penetrated in extreme environments, as well as stop bleeding from wounds in the oral cavity, nasal cavity, etc. Compared with the method of separately forming networks of the modified polysaccharide and polyvinyl alcohol and then mixing them, the three-dimensional network structure formed by the preparation method of the present invention has better interpenetration. The hemostatic material prepared by the method of the present invention has better swelling and water absorption properties, and at the same time has better hemostatic effects.

[0024] Optionally, in step (6), the product is first pre-frozen. The pre-freezing temperature is -80°C to -40°C, and the pre-freezing time is 1 h to 3 h; after pre-freezing, the product is placed in a freeze dryer for freeze-drying. Pre-freezing the product before freeze-drying can avoid deformation of the product during vacuum drying in a wet state, making the material surface more uniform and flat, and achieving better hemostatic functions.

[0025] Optionally, the freeze-drying parameters in step (6) are set as follows: Sublimation drying stage: the drying partition temperature is -10 to -30°C, the time is 9 h to 32 h, and the vacuum degree is 10 to 20 Pa; Desorption drying stage: the drying partition temperature is 10 to 50°C, and the time is 2 to 14 h. The freeze-drying parameters of the present invention are selected based on cost and the properties of the obtained product, which can ensure excellent reaction products while controlling costs, superior to the effects of methods outside the scope limited by the present invention.

[0026] The application forms of the product of the present invention include sponges, but are not limited to sponges, dressings, extended forms such as being pasted on gauze, etc. For different traumatic wounds, the product can be adjusted into different dosage forms for hemostasis, including hemostasis in body cavities, nasal hemostasis, external superficial trauma, etc.

[0027] The high-swelling antibacterial hemostatic material capable of rapid hemostasis of the present invention has a rapid and efficient hemostatic effect, and the antibacterial effect of the hemostatic material in vivo can reach more than 6 h.

[0028] The hemostatic material of the present invention forms a three-dimensional network structure through hierarchical cross-linking, has high swelling performance, can promote the self-coagulation process, has a dual-effect coagulation mechanism, can effectively block the bleeding of the wound, and has good biocompatibility.

[0029] The hemostatic material prepared by the present invention has instantaneous water absorption characteristics. It can be used for first aid hemostasis, especially for bleeding caused by large artery and vein injuries. It can also be used for tamponade hemostasis of bleeding in a confined space, such as nosebleed and ballistic injury hemostasis. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art.

[0031] Figure 1 It shows the dry and wet state effects of the hemostatic material prepared in Example 2 of the present invention.

[0032] Figure 2 It shows the antibacterial experiment results of the sample in Example 2. Detailed Embodiments

[0033] The following further illustrates the present invention with reference to embodiments. It should be understood that the embodiments are only used to further illustrate and explain the present invention, and are not used to limit the present invention.

[0034] Unless otherwise defined, the technical terms and scientific terms in this specification have the same meaning as those commonly understood by those skilled in the art. Although similar or identical methods and materials to those described herein can be applied in experiments or practical applications, the materials and methods are still described hereinafter. In case of conflict, the definition in this specification, including its definitions, shall prevail. Additionally, the materials, methods, and examples are for illustrative purposes only and are not restrictive.

[0035] Polyvinyl alcohol (PVA): sourced from Shanxi Jinyang Pharmaceutical Excipients Co., Ltd., batch number 20210304.

[0036] Sodium carboxymethyl cellulose: sourced from CPcekol, batch number AA638234.

[0037] Carboxymethyl chitosan: sourced from Weihai Daisu Pharmaceutical Co., Ltd., batch number PX161001.

[0038] Honey: sourced from Lanxi Hongxiang Biotechnology Co., Ltd., batch number 210501.

[0039] Example 1

[0040] 1) Add 20 g of PVA and 140 g of purified water to a three-necked flask, and stir and dissolve evenly at 90 °C at 350 r / min;

[0041] 2) Weigh 0.45 g of CaCl₂ and dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.9 g of sodium carboxymethyl cellulose and add it to the above solution, stirring to make it fully mixed evenly; then add 0.2 g of honey to the above sodium carboxymethyl cellulose solution, stirring evenly to obtain a blended polysaccharide solution;

[0042] 3) Mix the above PVA solution and the above blended polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat in a 60 °C water bath and under mechanical stirring at 1200 rpm, and carry out a cross-linking reaction for 3 h;

[0043] 4) After the cross-linking is completed, remove the water bath, keep stirring, add 3 g of pore-forming agent NaHCO₃ in multiple portions at intervals of 3 s, and stir for 2 h;

[0044] 5) After stirring, pour the blended solution into a mold and place it in an oven at 60 °C for curing for 6 h; after curing, take out the obtained product from the mold, rinse it with purified water and then ultrasonically clean it for 10 min;

[0045] 6) Pre-freeze the above product in a refrigerator at -80 °C for 2 h, and then put it into a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are set as follows: the temperature of the drying partition is -20 °C, the time is 20 h, and the vacuum degree is 20 Pa; in the analytical drying stage: the temperature of the drying partition is 25 °C, and the time is 10 h.

[0046] Example 2

[0047] 1) Add 20 g of PVA and 140 g of purified water to a three-necked flask, and stir and dissolve evenly at 90 °C at 350 r / min;

[0048] 2) Weigh 0.45 g of CaCl₂ and dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.6 g of sodium carboxymethyl cellulose and 0.3 g of carboxymethyl chitosan and add them to the above solution, stirring to make it fully mixed evenly; then add 0.2 g of honey to the above mixed solution, stirring evenly to obtain a blended polysaccharide solution;

[0049] 3) Mix the above PVA solution and the above blended polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat in a 60 °C water bath and under mechanical stirring at 1200 rpm, and carry out a cross-linking reaction for 3 h;

[0050] 4) After the crosslinking is completed, remove the water bath and keep stirring. Add 3 g of porogen NaHCO₃ in multiple portions at intervals of 3 s and stir for 2 h.

[0051] 5) After the stirring is completed, pour the blend solution into a mold and cure it in an oven at 60 °C for 6 h. After the curing is completed, take out the obtained product from the mold, rinse it with purified water and then ultrasonically clean it for 10 min.

[0052] 6) Pre-freeze the above product in a refrigerator at -80 °C for 2 h, and then put it into a freeze dryer for freeze-drying to obtain the hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0053] Example 3

[0054] 1) Add 20 g of PVA and 140 g of purified water into a three-necked flask, and stir and dissolve evenly at 90 °C at 350 r / min.

[0055] 2) Weigh 0.45 g of CaCl₂, dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.9 g of carboxymethyl chitosan and add it to the above solution, and stir to mix it evenly. Then add 0.2 g of honey to the above mixed solution and stir evenly to obtain a blend polysaccharide solution.

[0056] 3) Mix the above PVA solution and the above blend polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat it in a water bath at 60 °C and carry out a crosslinking reaction for 3 h under mechanical stirring at 1200 rpm.

[0057] 4) After the crosslinking is completed, remove the water bath and keep stirring. Add 3 g of porogen NaHCO₃ in multiple portions at intervals of 3 s and stir for 2 h.

[0058] 5) After the stirring is completed, pour the blend solution into a mold and cure it in an oven at 60 °C for 6 h. After the curing is completed, take out the obtained product from the mold, rinse it with purified water and then ultrasonically clean it for 10 min.

[0059] 6) Pre-freeze the above product in a refrigerator at -80 °C for 2 h, and then put it into a freeze dryer for freeze-drying to obtain the hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0060] Example 4

[0061] 1) Add 20 g of PVA and 140 g of purified water into a three-necked flask, and stir and dissolve evenly at 90 °C at 350 r / min.

[0062] 2) Weigh 0.45 g of CaCl₂ and dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.45 g of sodium carboxymethyl cellulose and 0.45 g of carboxymethyl chitosan and add them to the above solution, and stir to make them fully mixed evenly; then add 0.2 g of honey to the above mixed solution and stir evenly to obtain a blended polysaccharide solution;

[0063] 3) Mix the above PVA solution and the above blended polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat in a water bath at 60 °C and under mechanical stirring at 1200 rpm, and carry out a cross-linking reaction for 3 h;

[0064] 4) After the cross-linking is completed, remove the water bath, keep stirring, add 3 g of pore-forming agent NaHCO₃ in multiple portions at intervals of 3 s each, and stir for 2 h;

[0065] 5) After the stirring is completed, pour the blended solution into a mold and place it in an oven at 60 °C for curing for 6 h; after the curing is completed, take out the obtained product from the mold, rinse it with purified water and then ultrasonically clean it for 10 min;

[0066] 6) Pre-freeze the above product at -80 °C in a refrigerator for 2 h, and then place it in a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0067] Example 5

[0068] 1) Add 20 g of PVA and 140 g of purified water to a three-necked flask, and stir and dissolve evenly at 90 °C at 350 r / min;

[0069] 2) Weigh 0.45 g of CaCl₂ and dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.3 g of sodium carboxymethyl cellulose and 0.6 g of carboxymethyl chitosan and add them to the above solution, and stir to make them fully mixed evenly; then add 0.2 g of honey to the above mixed solution and stir evenly to obtain a blended polysaccharide solution;

[0070] 3) Mix the above PVA solution and the above blended polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat in a water bath at 60 °C and under mechanical stirring at 1200 rpm, and carry out a cross-linking reaction for 3 h;

[0071] 4) After the cross-linking is completed, remove the water bath, keep stirring, add 3 g of pore-forming agent NaHCO₃ in multiple portions at intervals of 3 s each, and stir for 2 h;

[0072] 5) After the stirring is completed, pour the blend solution into a mold and place it in an oven at 60 °C for curing for 6 h; after the curing is completed, take out the obtained product from the mold, rinse it with purified water, and then ultrasonically clean it for 10 min;

[0073] 6) Pre-freeze the above product at -80 °C in a refrigerator for 2 h, and then place it in a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0074] Example 6

[0075] 1) Add 20 g of PVA and 140 g of purified water to a three-necked flask, and stir and dissolve evenly at 90 °C at 350 r / min;

[0076] 2) Weigh 0.45 g of CaCl2, dissolve it in 36.6 g of purified water to prepare a CaCl2 solution, weigh 0.6 g of sodium carboxymethylcellulose and 0.3 g of carboxymethyl chitosan, add them to the above solution, and stir to mix them evenly; then add 0.2 g of honey to the above mixed solution and stir evenly to obtain a blend polysaccharide solution;

[0077] 3) Mix the above PVA solution and the above blend polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde, heat in a water bath at 60 °C, and under mechanical stirring at 1200 rpm, carry out a cross-linking reaction for 3 h;

[0078] 4) After the cross-linking is completed, remove the water bath, keep stirring, add 3 g of pore-forming agent NaHCO3 in multiple portions at intervals of 3 s, and stir for 2 h;

[0079] 5) After the stirring is completed, pour the blend solution into a mold and place it in an oven at 60 °C for curing for 6 h; after the curing is completed, take out the obtained product from the mold, rinse it with purified water, and then ultrasonically clean it for 10 min;

[0080] 6) Pre-freeze the above product at -80 °C in a refrigerator for 2 h, and then place it in a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0081] Example 7

[0082] 1) Add 20 g of PVA and 140 g of purified water to a three-necked flask, and stir and dissolve evenly at 90 °C at 350 r / min;

[0083] 2) Weigh 0.45 g of CaCl₂ and dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.6 g of sodium carboxymethyl cellulose and 0.3 g of carboxymethyl chitosan and add them to the above solution, stirring to make them fully mixed and uniform; then add 0.1 g of honey to the above mixed solution and stir evenly to obtain a blended polysaccharide solution;

[0084] 3) Mix the above PVA solution and the above blended polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat in a 60 °C water bath and carry out a cross-linking reaction for 3 h under mechanical stirring at 1200 rpm;

[0085] 4) After the cross-linking is completed, remove the water bath and keep stirring. Add 3 g of pore-forming agent NaHCO₃ in multiple portions at intervals of 3 s and stir for 2 h;

[0086] 5) After the stirring is completed, pour the blended solution into a mold and place it in an oven at 60 °C for curing for 6 h; after the curing is completed, take out the obtained product from the mold, rinse it with purified water and then ultrasonically clean it for 10 min;

[0087] 6) Pre-freeze the above product in a refrigerator at -80 °C for 2 h and then put it into a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0088] Example 8

[0089] 1) Add 20 g of PVA and 140 g of purified water to a three-necked flask and stir and dissolve evenly at 90 °C at 350 r / min;

[0090] 2) Weigh 0.45 g of CaCl₂ and dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.6 g of sodium carboxymethyl cellulose and 0.3 g of carboxymethyl chitosan and add them to the above solution, stirring to make them fully mixed and uniform; then add 1 g of honey to the above mixed solution and stir evenly to obtain a blended polysaccharide solution;

[0091] 3) Mix the above PVA solution and the above blended polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat in a 60 °C water bath and carry out a cross-linking reaction for 3 h under mechanical stirring at 1200 rpm;

[0092] 4) After the cross-linking is completed, remove the water bath and keep stirring. Add 3 g of pore-forming agent NaHCO₃ in multiple portions at intervals of 3 s and stir for 2 h;

[0093] 5) After the stirring is completed, pour the blended solution into a mold and place it in an oven at 60 °C for curing for 6 h; after the curing is completed, take out the obtained product from the mold, rinse it with purified water, and then ultrasonically clean it for 10 min;

[0094] 6) Pre-freeze the above product at -80 °C in a refrigerator for 2 h, and then place it in a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0095] Example 9

[0096] 1) Add 20 g of PVA and 140 g of purified water to a three-necked flask, stir and dissolve evenly at 90 °C at 350 r / min; add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde, heat in a water bath at 60 °C, and under mechanical stirring at 1200 rpm, carry out a cross-linking reaction for 3 h;

[0097] 2) Weigh 0.45 g of CaCl2, dissolve it in 36.6 g of purified water to prepare a CaCl2 solution, weigh 0.6 g of sodium carboxymethyl cellulose and 0.3 g of carboxymethyl chitosan, add them to the above solution, and stir to make them fully mixed evenly; then add 0.2 g of honey to the above mixed solution and stir evenly to obtain a blended polysaccharide solution;

[0098] 3) Mix the above cross-linked PVA solution and the above blended polysaccharide solution;

[0099] 4) Keep stirring, add 3 g of pore-forming agent NaHCO3 in multiple times at intervals of 3 s, and stir for 2 h;

[0100] 5) After the stirring is completed, pour the blended solution into a mold and place it in an oven at 60 °C for curing for 6 h; after the curing is completed, take out the obtained product from the mold, rinse it with purified water, and then ultrasonically clean it for 10 min;

[0101] 6) Pre-freeze the above product at -80 °C in a refrigerator for 2 h, and then place it in a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0102] Example 10

[0103] 1) Add 10 g of PVA and 140 g of purified water to a three-necked flask, stir and dissolve evenly at 90 °C at 350 r / min;

[0104] 2) Weigh 0.45 g of CaCl₂ and dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.6 g of sodium carboxymethyl cellulose and 0.3 g of carboxymethyl chitosan and add them to the above solution, stirring to make them fully mixed and uniform; then add 0.2 g of honey to the above mixed solution and stir evenly to obtain a blend polysaccharide solution;

[0105] 3) Mix the above PVA solution and the above blend polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat in a 60 °C water bath and carry out a cross-linking reaction for 3 h under mechanical stirring at 1200 rpm;

[0106] 4) After the cross-linking is completed, remove the water bath and keep stirring. Add 3 g of pore-forming agent NaHCO₃ in multiple portions at intervals of 3 s and stir for 2 h;

[0107] 5) After the stirring is completed, pour the blend solution into a mold and place it in an oven at 60 °C for curing for 6 h; after curing, take out the obtained product from the mold, rinse it with purified water and then ultrasonically clean it for 10 min;

[0108] 6) Pre-freeze the above product in a refrigerator at -80 °C for 2 h, and then put it into a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0109] Through the verification methods of Experimental Examples 1 - 3, the properties of the product of Example 10 are similar to those of Example 2.

[0110] Example 11

[0111] 1) Add 50 g of PVA and 140 g of purified water to a three-necked flask and stir to dissolve evenly at 90 °C at 350 r / min;

[0112] 2) Weigh 0.45 g of CaCl₂ and dissolve it in 36.6 g of purified water to prepare a CaCl₂ solution. Weigh 0.6 g of sodium carboxymethyl cellulose and 0.3 g of carboxymethyl chitosan and add them to the above solution, stirring to make them fully mixed and uniform; then add 0.2 g of honey to the above mixed solution and stir evenly to obtain a blend polysaccharide solution;

[0113] 3) Mix the above PVA solution and the above blend polysaccharide solution, adjust the solution temperature to 60 °C, and simultaneously add 4 ml of catalyst HCl and 2.35 ml of glutaraldehyde. Heat in a 60 °C water bath and carry out a cross-linking reaction for 3 h under mechanical stirring at 1200 rpm;

[0114] 4) After the cross-linking is completed, remove the water bath and keep stirring. Add 3 g of pore-forming agent NaHCO₃ in multiple portions at intervals of 3 s and stir for 2 h;

[0115] 5) After the stirring is completed, pour the blend solution into a mold and cure it in an oven at 60 °C for 6 h; after the curing is completed, take out the obtained product from the mold, rinse it with purified water and then ultrasonically clean it for 10 min;

[0116] 6) Pre-freeze the above product in a refrigerator at -80 °C for 2 h, and then put it into a freeze dryer for freeze-drying to obtain a hemostatic material. The freeze-drying parameters are the same as those in Example 1.

[0117] Through the verification methods of Experimental Examples 1-3, the properties of the product of Example 10 are similar to those of Example 2.

[0118] Experimental Example 1 Verification of Swelling and Adsorption Properties of Hemostatic Material

[0119] Cut the hemostatic materials obtained in the above Examples 1-9 into pieces with a size of 25 mm * 25 mm * 10 mm, accurately weigh them and place them in a nylon cloth bag, then immerse them in distilled water (pH = 7.0, temperature 25 °C), allow them to naturally absorb water and swell at room temperature, take out the cloth bag after 30 minutes, absorb the water on the surface of the cloth bag, weigh the mass of the sample after absorbing the liquid, and calculate the water absorption ratio and swelling ratio.

[0120] The formula for calculating the water absorption ratio Q is as follows:

[0121] Q = (m2 - m1) / m l . Where: Q is the water absorption ratio, unit: g / g; m l is the mass of the sample before absorbing the liquid, unit: g; m2 is the mass of the sample after absorbing the liquid, unit: g.

[0122] The formula for calculating the swelling ratio (swellability) D is as follows:

[0123] D = (V2 - V1) / m l . Where: D is the swelling ratio, unit: mm 3 / mm 3 ; V l is the volume of the sample before absorbing the liquid, unit: mm 3 ; V2 is the volume of the sample after absorbing the liquid, unit: mm 3 .

[0124] Table 1 Verification of water absorption ratio and swelling ratio of products in Examples 1-9

[0125] Example Swelling Ratio Water Absorption Ratio Example 1 5.39±0.10 13.6±0.4 Example 2 8.68±0.33 15.8±0.5 Example 3 7.53±0.24 14.2±0.4 Example 4 7.61±0.31 15.5±0.2 Example 5 7.56±0.25 15.4±0.2 Example 6 8.15±0.21 15.2±0.3 Example 7 8.21±0.12 15.4±0.2 Example 8 8.41±0.12 15.3±0.1 Example 9 5.61±1.65 14.4±0.4

[0126] Experimental Example 2 Verification of In Vitro Coagulation Properties of Hemostatic Material

[0127] Verify the in vitro clotting time performance of the hemostatic materials prepared in Examples 1-9, Yunnan Baiyao and normal saline.

[0128] Plasma preparation: Blood was collected from the marginal ear vein of healthy rabbits while they were awake and not administered with drugs. The blood was anticoagulated with 3.8 wt% sodium citrate at a volume ratio of 9:1 and gently inverted and mixed evenly. Then it was centrifuged at 3500 revolutions per minute for 10 minutes, and the supernatant was collected to obtain the plasma.

[0129] The activated partial thromboplastin time of New Zealand rabbits was measured by the coagulation method. The hemostatic materials prepared in Examples 1-9 were made into solutions with a certain concentration (5 mg / ml). 50 μL of each solution was taken and added to 100 μL of the prepared plasma. Then 100 μL of activated partial thromboplastin suspension (APTT), thromboplastin (PT), and thrombin (TT) were respectively added. After incubation at 37 °C for 5 min, 100 μL of 0.025 mol / L calcium chloride solution pre-warmed at 37 °C was added, and the coagulation time was recorded, which was the APTT value (s), PT value (s), and TT value (s).

[0130] The in vitro test data of coagulation factors APTT, TT, and PT are shown as follows (see Table 2 below).

[0131] Table 2 Verification of in vitro coagulation time of the products in Examples 1-9

[0132]

[0133] In vitro coagulation time: Thrombin time (TT) refers to the coagulation time of blood after adding standardized prothrombin to plasma. It is mainly affected by the fibrinogen level, coagulation activity, and cross-linking of fibrin in plasma. The length of TT reflects the level of the common pathway of coagulation factors and can clarify the interaction between surgical absorbable materials and blood at the molecular level. Prothrombin time (PT) refers to the coagulation time of blood after prothrombin becomes thrombin. Prothrombin time (PT) is an index describing the extrinsic coagulation system. The length of PT reflects the levels of prothrombin, fibrinogen, and coagulation factors V, VII, and X in plasma. Activated partial thromboplastin time (APTT) is the phospholipid plasma recalcification time. The length of APTT reflects the levels of prothrombin, fibrinogen, and factors V and X in the common pathway of coagulation factors in the intrinsic coagulation system in plasma.

[0134] Compared with the negative control group, the thrombin time (TT), prothrombin time (PT), and activated partial thromboplastin time (APTT) of the hemostatic materials in Examples 1-9 were all lower than those of the negative control group, indicating that each example in the present invention has a certain effect of promoting blood coagulation. Compared with Yunnan Baiyao, the technical effects of the examples of the present invention are also prominent and excellent.

[0135] Experimental Example 3 Bacteriostatic Experiment

[0136] Pour the Staphylococcus aureus bacterial solution into the sterilized and cooled liquid medium, place it in a shaker (rotation speed 100 r / min) and culture at 37°C for 12 h, then dilute it, and determine the bacterial solution concentration by the microscopic counting method. The concentration of Staphylococcus aureus is measured as 1×10 6 CFU / ml.

[0137] Weigh an appropriate amount of the sample prepared in Example 2, add 200 ml of purified water, and use a homogenizer to homogenize it into a uniform solution with a concentration of 0.5%, and prepare 150 ml of the corresponding liquid medium. Sterilize the prepared sample solution and the medium at 121°C for 15 min, then respectively measure 8 ml, 4 ml, and 2 ml of this solution into test tubes, add the liquid medium to 20 ml and mix evenly, so that the concentration (W / V) of the sample in Example 2 is 0.2%, 0.1%, and 0.05% respectively. Then, after cooling, take 200 μl of the bacterial suspension with a sterile pipette and add it to the test tube, and gently shake it evenly; measure the initial absorbance value of the sample at a wavelength of 600 nm with a spectrophotometer, and then place it in a constant temperature incubator at 37°C for culture. Measure the absorbance value of the sample at 24 h, 48 h, 72 h, 96 h, 120 h, 144 h, 168 h, and 216 h respectively. The change in the absorbance value reflects the change in the turbidity of the bacterial solution, that is, the change in the number of bacteria. Use the medium without the bacterial suspension as a blank, and at the same time set the medium without the sample solution in Example 2 as a control, with the same other conditions. The results are shown in Figure 2 .

[0138] According to Figure 2 the experimental results shown, the hemostatic material of the present invention has an obvious antibacterial effect.

[0139] It should be understood that the present invention disclosed is not limited to the specific methods, schemes, and substances described, as these can all vary. It should also be understood that the terms used herein are only for the purpose of describing specific embodiments, and are not intended to limit the scope of the present invention. The scope of the present invention is only limited by the appended claims.

[0140] Those skilled in the art will also recognize, or be able to confirm, many equivalents of the specific embodiments of the present invention described herein using no more than routine experimentation. These equivalents are also included in the appended claims.

Claims

1. A highly expandable hemostatic material, characterized in that, By weight parts, the high-swelling hemostatic material comprises 10 - 50 parts of polyvinyl alcohol and 0.5 - 10 parts of modified polysaccharide, wherein the modified polysaccharide is a mixture of sodium carboxymethyl cellulose and carboxymethyl chitosan, and the mass ratio range of sodium carboxymethyl cellulose to carboxymethyl chitosan is 2.9 - 0.1:0.1 - 2.9; The preparation method of the hemostatic material comprises the following steps: (1) Dissolve the polyvinyl alcohol in water to obtain a polyvinyl alcohol aqueous solution; (2) Dissolve the modified polysaccharide in a calcium salt solution for complexation to obtain a first network solution; (3) Mix the polyvinyl alcohol aqueous solution obtained in step (1) with the first network solution to obtain a blend solution, add a catalyst and a crosslinking agent to carry out a crosslinking reaction to obtain a second network solution; (4) After the crosslinking reaction in step (3) is completed, add a pore-forming agent and stir for 1 - 5 h; (5) After step (4) is completed, cure the product at 50 - 80 °C for 5 - 24 h; (6) Put the product obtained in step (5) into a freeze dryer for freeze-drying to obtain the product.

2. The hemostatic material according to claim 1, wherein, In the modified polysaccharide, the mass ratio range of sodium carboxymethyl cellulose to carboxymethyl chitosan is 1.5 - 2.5:2.5 - 1.

5.

3. The hemostatic material according to claim 1, characterized in that, The degree of alcoholysis of the polyvinyl alcohol is 77% - 99%.

4. The hemostatic material according to claim 1, characterized in that By weight parts, the hemostatic material further comprises 0.1 - 10 parts of an antibacterial component, and the antibacterial component comprises honey.

5. The hemostatic material according to claim 4, wherein The honey is 0.1 - 5 parts.

6. The hemostatic material according to claim 5, characterized in that, The honey is 0.15 - 0.5 parts.

7. A method for preparing the hemostatic material according to any one of claims 1-6, characterized in that, It comprises the following steps: (1) Dissolve the polyvinyl alcohol in water at 80 - 90 °C to obtain a polyvinyl alcohol aqueous solution; (2) Dissolve the modified polysaccharide in a calcium salt solution for complexation to obtain a first network solution; the calcium salt is selected from any one of calcium chloride, calcium oxalate and calcium sulfate; (3) Mix the polyvinyl alcohol aqueous solution obtained in step (1) with the first network solution to obtain a blend solution, add a catalyst and a crosslinking agent to carry out a crosslinking reaction to obtain a second network solution; the catalyst is an inorganic acid, and the crosslinking agent is selected from one or more of formaldehyde, acetaldehyde, glutaraldehyde and hexanedial; (4) After the crosslinking reaction in step (3) is completed, add a pore-forming agent and stir for 1 - 5 h; the pore-forming agent is starch or carbonate; (5) After step (4) is completed, cure the product at 50 - 80 °C for 5 - 24 h; after curing, wash the product with water until it is neutral; (6) Put the product obtained in step (5) into a freeze dryer for freeze-drying to obtain the product.

8. The preparation method according to claim 7, characterized in that, In step (2), add an antibacterial component to the first network solution.

9. The preparation method according to claim 7, wherein the calcium salt solution in step (2) is a 2 mass% - 10 mass% calcium salt solution.

10. The preparation method according to claim 7, wherein the crosslinking reaction conditions in step (3) are heating in a water bath at 30 - 60 °C and carrying out the crosslinking reaction for 1 - 5 h under mechanical stirring at 200 - 2500 rpm.

11. For the preparation method according to claim 7, in step (3), based on the blend solution, the content of the crosslinking agent is 0.05% to 5% by mass; the content of the pore-forming agent is 15% to 60% by mass; the content of the catalyst is 0.05% to 5% by mass.

12. For the preparation method according to claim 7, in step (6), first pre-freeze the product, the pre-freezing temperature is -80°C to -40°C, and the pre-freezing time is 1 h to 3 h; after the pre-freezing is completed, put the product into a freeze dryer for freeze-drying.

13. For the preparation method according to claim 7, the freeze-drying parameters in step (6) are set as follows: sublimation drying stage: the temperature of the drying partition is -10 to -30°C, the time is 9 h to 32 h, and the vacuum degree is 10 to 20 Pa; analytical drying stage: the temperature of the drying partition is 10 to 50°C, and the time is 2 to 14 h.

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