CN119303149A

CN119303149A - A composite hemostatic material for quickly controlling non-compressive bleeding and a preparation method thereof

Info

Publication number: CN119303149A
Application number: CN202411874018.4A
Authority: CN
Inventors: 张先龙; 冯守业; 郭少云
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2024-12-19
Filing date: 2024-12-19
Publication date: 2025-01-14
Anticipated expiration: 2044-12-19
Also published as: CN119303149B

Abstract

The invention belongs to the technical field of hemostatic materials and provides a composite hemostatic material for rapidly controlling non-compression bleeding and a preparation method thereof, wherein the method comprises the steps of S1 grafting 2, 3-epoxypropyl trimethyl ammonium chloride through sodium alginate to obtain quaternized sodium alginate, S2 dissolving polyvinyl alcohol to obtain a polyvinyl alcohol aqueous solution, S3 carrying out hydroformylation modification on glucan to obtain a hydroformylation modified glucan solution, S4 adding the hydroformylation modified glucan solution into the polyvinyl alcohol aqueous solution, then adding quaternized sodium alginate to obtain a mixed solution, S5 foaming, defoaming and freeze-drying the mixed solution to obtain aerogel, and S6 washing and freeze-drying the aerogel to obtain the composite hemostatic material.

Description

Composite hemostatic material for rapidly controlling non-compression hemorrhage and preparation method thereof

Technical Field

The invention belongs to the technical field of hemostatic materials, and particularly relates to a composite hemostatic material for rapidly controlling non-compression hemorrhage and a preparation method thereof.

Background

Blood is an important transport vehicle in humans responsible for the delivery of oxygen and nutrients, and severe blood loss can lead to symptoms of dizziness, shock and organ failure. Bleeding is a major cause of death in traumatic injuries, as massive blood loss often results in serious complications, including hypotension and multiple organ dysfunction. More than 30% of traumatic deaths worldwide are due to uncontrolled bleeding, with more than half of the deaths occurring before emergency treatment. Although many reported or sold hemostatic agents have a high hemostatic effect on body surface bleeding wounds, such as tissue gelatin, glutaraldehyde-crosslinked albumin or gelatin-based hemostatic agents, they generally have poor effects on deep wounds caused by small caliber firearms and simple explosive devices in battlefield and daily life. Because these wounds are often irregularly shaped, it is even more challenging that they are incompressible hemorrhages.

For incompressible bleeding, gauze and sponge cannot enter the bleeding part, and the hemostatic effect is difficult to achieve. Conventional powders are difficult to quickly form stable scabs on wounds and often difficult to prevent static and arterial bleeding. Researchers have developed inflatable hemostats that can be delivered to an internal hemorrhage site to expand to stop bleeding after absorption of blood. Although the novel hemostatic drug exhibits a good hemostatic effect in hemostasis of non-compression hemorrhage, there are limitations. The X-shaped rapid hemostatic system (XStatTM) containing a large amount of compressed cellulose sponge is highly adhesive and non-biodegradable, and potential post-operative residues can cause post-operative injury, requiring even a second surgical resection. Many shape memory polymer hemostats have limited absorption of blood, have poor compression strength, require tens of seconds or even tens of seconds or more to recover shape, and tend to extend hemostasis time and may result in increased blood loss. Chinese patent CN115300665A discloses an antibacterial absorbable nasal hemostatic sponge, which comprises the following components in parts by mass of gelatin, chitosan, polyvinyl alcohol, sodium alginate, polylactic acid and a cross-linking agent in a ratio of 2 (1-2) to 1:2 (0.003-0.005). However, the polyvinyl alcohol of the antibacterial absorbable nasal hemostatic sponge is mixed with sodium alginate and a separate elastomeric material is required. Thus, it would be desirable to develop a composite hemostatic material that has rapid blood-sucking expansion, biodegradability and for rapid control of fatal non-compressive non-compression bleeding, and this remains a continuing challenge.

Disclosure of Invention

Aiming at the problem of how to quickly stop bleeding due to incompressible bleeding, the invention provides a composite hemostatic material for quickly controlling the non-compression bleeding and a preparation method thereof, and aims to prepare a hemostatic material with quick blood sucking and expanding property, biodegradability and for the non-compression bleeding.

The invention is realized by the following technical scheme:

a method for preparing a composite hemostatic material for rapidly controlling non-compression bleeding, comprising the steps of:

s1, mixing sodium alginate, 2, 3-epoxypropyl trimethyl ammonium chloride and deionized water to carry out quaternization reaction, and then regulating pH to obtain quaternized sodium alginate;

s2, dissolving 1788 type polyvinyl alcohol in deionized water, and then heating and stirring to obtain 1788 type polyvinyl alcohol aqueous solution;

S3, acidizing the aqueous solution of the glucan, and then adding an aldehyde modifier to carry out a modification reaction to obtain an aldehyde modified glucan solution;

s4, adding the aldehyde modified glucan solution into the 1788 type polyvinyl alcohol aqueous solution, and then adding quaternized sodium alginate to obtain a mixed solution;

s5, stirring and foaming, vacuum defoaming and freeze drying are sequentially carried out on the mixed solution to obtain freeze-dried aerogel;

And S6, cleaning the freeze-dried aerogel in sequence, adjusting the pH value, and freeze-drying to obtain the composite hemostatic material.

The preparation mechanism and the beneficial effects of the invention are as follows:

the sodium alginate is modified by adopting 2, 3-epoxypropyl trimethyl ammonium chloride as a quaternary ammonium reagent and introducing cationic groups, so that cations carried by the sodium alginate can interact with negatively charged bacterial walls, and the modified quaternized sodium alginate has antibacterial property.

By dissolving 1788 type polyvinyl alcohol in water, the intermolecular hydrogen bond of 1788 type polyvinyl alcohol can be destroyed, and the 1788 type polyvinyl alcohol is fully dissolved, so that the 1788 type polyvinyl alcohol can be fully mixed with other materials for reaction;

The polysaccharide structure containing multi-aldehyde groups of macromolecules can be prepared as a cross-linking agent by acidizing the glucan aqueous solution and adding an aldehyde modifier, the high aldehyde group density of the molecular chain of the polysaccharide structure can form a local high-density cross-linking network system with a matrix, meanwhile, the cross-linking agent macromolecular structure can cross a plurality of cross-linking network areas, the stability among cross-linking networks is improved, the whole material forms a stable interconnected sea-island structure, and the double-cross-linking network system of the sea-island structure can endow the composite material with high mechanical strength, good imbibition expansion degree and excellent hemostatic performance.

In the step S5, hydrochloric acid is specifically adopted as an acid catalyst, after the system is kept stand to room temperature, the acid catalyst is added under stirring, then the foaming reaction is fully stirred, and the hydroxyl groups of 1788 polyvinyl alcohol and quaternized sodium alginate and the active aldehyde groups of the cross-linking agent are promoted to form a hemiacetal bond by the addition of the acid catalyst, wherein the reaction is slow due to the water solvent of the system and the macromolecular structure of the cross-linking agent, the viscosity of the system is high, and the system is further foamed by fully stirring, so that the porosity of a final material is improved.

Through adopting the vacuum defoamation, can get rid of the inhomogeneous big bubble in the stirring process, and then avoid because system pore size is uneven to lead to the architecture to be destroyed, influence composite material's imbibition performance, reduce material mechanical strength, reduce hemostatic efficiency's the adverse event.

In summary, the invention improves the antibacterial property of the sodium alginate by quaternization, and makes the sodium alginate fully crosslinked with 1788 type polyvinyl alcohol serving as a skeleton structure under the action of crosslinking agent hydroformylation modified glucan to form a sea-island structure, and further improves the porosity, the pore size and the mechanical strength by combining post-treatments such as foaming, vacuum defoaming, freeze drying and the like, thereby improving the hemostatic performance of the composite material.

Further, in the step S1, the mass ratio of the sodium alginate to the 2, 3-epoxypropyl trimethyl ammonium chloride is (2-8): 3-8.

In step S3, the mass ratio of the glucan to the glutaraldehyde is (0.5-3.5) (0.5-1.6).

Further, in step S1, the pH value is less than or equal to 7.

In the invention, in the step S1, after the pH value is regulated, excessive ethanol is adopted for precipitation, and the product is collected and dried, so that the quaternized sodium alginate is finally obtained.

Further, in step S6, the pH is 7 to 8.

In the invention, the pH value in the step S6 is regulated by adopting sodium bicarbonate solution with the mass fraction of 7.75%, and the acid catalyst is obtained by removing the original system, so that the hemostatic performance of the material is prevented from being influenced by acid impurities in the material.

In step S3, the molecular weight of glucose in the aqueous dextran solution is 60000-80000.

In the invention, the molecular weight of the aldehyde modified glucan is controlled by adjusting the molecular weight of glucose, and the crosslinked network system of the system is controlled, so that the porosity, the pore size and the mechanical property of the material are controlled, and finally the composite material with optimal hemostatic property is obtained.

Further, the modifier comprises at least one of glutaraldehyde and glyoxal.

Further, in step S3, hydrochloric acid with a mass fraction of 3.3% is used for the acidification treatment.

Further, in the step S5, the treatment temperature of the first stage of vacuum defoaming is-35 to-20 ℃, the treatment time is 2-4 hours, the treatment temperature of the second stage is-50 to 0 ℃, and the treatment time is 24-48 hours.

The size and the quantity of ice crystals of the system can be effectively regulated by regulating the pre-freezing (the first-stage treatment temperature) and the freezing (the second-stage treatment temperature) drying temperature, so that the porosity and the pore size of the composite material are regulated. The cross-linking reaction of the composite material occurs along with the freeze-drying water loss process, and the system shape and structure are basically fixed, so that the customized regulation and control of the porosity and the pore size are facilitated.

The second aim of the invention is to provide a composite hemostatic material obtained by the preparation method of any one of the above steps:

The composite hemostatic material comprises, by weight, 1-10 parts of quaternized sodium alginate, 10-15 parts of 1788 type polyvinyl alcohol and 0.1-5 parts of aldehyde modified glucan.

The technical mechanism and the beneficial effects of the invention are as follows:

The invention takes 1788 type polyvinyl alcohol and quaternized sodium alginate as matrix materials, wherein, 1788 type polyvinyl alcohol is taken as a skeleton structure of a composite material, which gives the material good mechanical property to play a role in supporting intelligent hemostasis of wounds, while quaternized sodium alginate has excellent biocompatibility, can promote wound healing and hemostasis, and the mixture ratio is mutually adjusted with 1788 type polyvinyl alcohol, thus the composite hemostatic material can play a role in supporting auxiliary hemostasis of wounds, and can not cause secondary injury to wounds due to overhigh mechanical strength;

Furthermore, the invention abandons the traditional small molecular cross-linking agent, selects the modified polyaldehyde polysaccharide cross-linking agent, forms a local high-density cross-linking network system, and simultaneously, the macromolecular structure of the cross-linking agent can span a plurality of cross-linking network areas to improve the stability among cross-linking networks, and the whole material forms a stable interconnected island structure to endow the composite material with high mechanical strength, good liquid absorption expansion degree and excellent hemostatic performance.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a 3D structure diagram of simulated reduction of Micro-CT of initial lyophilized samples (a, c) and post-water-washed secondary lyophilized samples (b, D) of the composite hemostatic material provided in example 1 of the present application;

fig. 2 is a schematic diagram of a composite hemostatic material according to embodiment 1 of the present application in an initial state (a), compression (b) and imbibition re-expansion (c) simulation test;

FIG. 3 is an SEM image of the composite hemostatic material provided in example 1 of the present application in an initial state of a (500 μm), d (20 μm), compressed b (500 μm), e (20 μm), and imbibed re-expansion c (500 μm), f (20 μm) simulation test.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

Example 1

The embodiment provides a composite hemostatic material for rapidly controlling non-compression hemorrhage, and a preparation method thereof specifically comprises the following steps:

(1) 1788 polyvinyl alcohol (Bi De medical, purity 1788), sodium alginate (Shanghai Ala chemical Co., ltd., viscosity 200+ -20 mPa s), 2, 3-epoxypropyl trimethyl ammonium chloride (Shanghai Ala chemical Co., ltd. Gtoreq.95%), dextran (Shanghai Michelin chemical Co., ltd., molecular weight 70000), glutaraldehyde 50% (Cheng Long chemical Co., analytical grade), hydrochloric acid (Cheng Long chemical Co., ltd., purity 20%), sodium bicarbonate (Shanghai Ala chemical Co., ltd., AR,. Gtoreq.99.8%);

(2) Weighing and preparing the raw materials, wherein the weight ratio of the raw materials is 1788, namely polyvinyl alcohol, sodium alginate, 2, 3-epoxypropyl trimethyl ammonium chloride, dextran, glutaraldehyde, hydrochloric acid and sodium bicarbonate solution is 10:3:5.145:0.672:1.6:5:3;

(3) Dissolving sodium alginate in deionized water, fully stirring until the sodium alginate is fully dissolved, adding 2, 3-epoxypropyl trimethyl ammonium chloride, fully stirring, and placing the reaction in a 60 ℃ stirrer to avoid light for 24 hours;

(4) The pH was adjusted to below 7 and then left at room temperature. Adding excessive ethanol for precipitation, collecting the product, and drying to obtain quaternized sodium alginate;

(5) Dissolving 1788 type polyvinyl alcohol in deionized water, and stirring for 2 hours at the temperature of 90 ℃ at the rotation speed of 1200 rpm;

(6) Adding 8.25 ml hydrochloric acid into a 50ml volumetric flask, and adding deionized water for dilution to obtain hydrochloric acid with a mass fraction of 3.3%;

(7) Dissolving glucan in deionized water, adding hydrochloric acid for acidification, adding glutaraldehyde solution for stirring reaction to obtain glutaraldehyde modified glucan;

(8) Mixing 1788 type polyvinyl alcohol solution and polyaldehyde dextran solution, stirring and mixing at 50deg.C;

(9) Adding quaternized sodium alginate into the solution (8) under the stirring condition, and stirring and reacting for 1 hour at 50 ℃ at the rotating speed of 1200 rpm;

(10) Pouring the mixed solution into a beaker, standing to room temperature, gradually adding hydrochloric acid for acidification, and stirring and foaming for 1.5 hours at a rotating speed of 1800 rpm;

(11) Pouring the foam solution into a mold, vacuum defoaming, pre-freezing for 4 hours at the temperature of minus 35 ℃, and freeze-drying the sample for 48 hours at the temperature of minus 50 ℃ to obtain freeze-dried aerogel;

(12) Dissolving 4g sodium bicarbonate in deionized water, pouring into a 50ml volumetric flask for dilution, and obtaining sodium bicarbonate solution with the mass fraction of 7.75%;

(13) And (3) putting the freeze-dried aerogel in the step (11) into deionized water, flushing for 1 hour, adding sodium bicarbonate solution to adjust the pH of the solution to 7-8, pre-freezing for 4 hours at the temperature of minus 35 ℃, and freeze-drying the sample for 24 hours at the temperature of minus 50 ℃ to finally obtain the composite hemostatic material for rapidly controlling non-compression bleeding.

The microstructure of the material was characterized by Scanning Electron Microscopy (SEM). Microscopic average pore diameters of the materials were measured using ImageJ software (version 1.53 k). The porosity of the material is measured by adopting a liquid displacement method according to the national standard GB/T33052-2016.

One of the key factors affecting the hemostatic performance of the material is the hydrophilicity of the hemostatic material. The water contact angle is a suitable parameter for determining the hydrophilicity and hydrophobicity of all finished surfaces. The composite hemostatic material prepared by the invention has good hydrophilic performance and a complex pore canal structure, and in order to better reflect the hydrophilic performance of the material, a contact angle analyzer (DATA PHYSICS Instruments, DSA30, germany) is used for measuring the retention time of 4 mu L liquid drops on the surface of the composite hemostatic material and the contact angle of the liquid drops with sponge when the liquid drops stay on the surface of the composite hemostatic material for 3 rd s. The liquid absorption rate and the liquid absorption expansion degree of the composite hemostatic material are tested by referring to the standard YY/T1803-2021 of the pharmaceutical industry standard, a piece of composite hemostatic material is soaked in PBS solution until the sponge is soaked by liquid, and the liquid absorption capacity and the liquid absorption expansion degree of the sponge are obtained through weight and volume changes.

The mechanical strength and anti-fatigue ability of the composite hemostatic material after imbibition expansion are important factors in providing a stable physical hemostatic barrier. And testing by using a Shenzhen New think carefully material detection Co., ltd CMT4104 universal tester, and performing stress strain test on the composite hemostatic material. The material was compressed to 85% strain at a rate of 5 mm/s in each cycle, recovered at the same rate, and repeated five times.

And (3) evaluating the hemostatic effect of the composite hemostatic material by adopting a rat liver cross incision hemostatic model, a rat liver standard disc-shaped loss hemostatic model and a rat femoral artery transverse incision hemostatic model. The composite hemostatic material slice (thickness 5mm, side 15 mm) was sterilized by irradiation with ultraviolet light for 1 hour. Rats were anesthetized with 10% chloral hydrate and fixed on plates. All animal experiments were conducted strictly in accordance with guidelines of the National Institutes of Health (NIH) for laboratory animal care and use.

The average pore diameter of the material was found to be 29.8 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 3 s, and the contact angle of the material is 0 degree in three seconds. The porosity of the composite hemostatic material is 84.17%, the liquid absorption rate is 3590%, the liquid absorption expansion degree is 8046%, and the compression strength is 166.23 Kpa. The blood loss of the composite hemostatic material in the rat liver cross incision hemostatic model, the rat liver standard disc-shaped loss hemostatic model and the rat femoral artery transverse incision hemostatic model is respectively 0.32 g, 0.6 g and 1.1 g.

From the Micro-CT simulated reduction 3D structure of the initial freeze-dried samples (a and c) and the secondary freeze-dried samples (b and D) of the composite hemostatic material after washing in FIG. 1, the porosity of the samples subjected to the secondary freeze-drying after washing in water is obviously improved, and the density of the samples is obviously reduced. As can be seen from the schematic diagram of fig. 2 in the simulation test of the composite hemostatic material in the initial state (a), compression (b) and imbibition re-expansion (c), the composite hemostatic material absorbs water again after compression, and can recover the original state with a certain degree of expansion. From the SEM images of the composite hemostatic material in the initial states a (500 μm), d (20 μm), compressed b (500 μm), e (20 μm) and imbibition re-expansion c (500 μm), f (20 μm) in the simulation test, it can be seen that the pore structure of the composite hemostatic material is still intact after imbibition re-expansion after compression in the SEM images.

Example 2

The difference between the embodiment and the embodiment 1 is that the weight ratio of the prepared materials is 1788, the weight ratio of the polyvinyl alcohol, the sodium alginate, the 2, 3-epoxypropyl trimethyl ammonium chloride, the dextran, the glutaraldehyde, the hydrochloric acid and the sodium bicarbonate solution is 10:3:5.145:0.51:1:5:3.

The average pore diameter of the material was found to be 40.0 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 4.3 s, and the contact angle of the material is 55.78 degrees at three seconds. The porosity of the composite hemostatic material is 87.58%, the liquid absorption rate is 3758%, the liquid absorption expansion degree is 973.6%, and the compression strength is 157.14 Kpa. The blood loss of the composite hemostatic material in the rat liver cross incision hemostatic model, the rat liver standard disc-shaped loss hemostatic model and the rat femoral artery transverse incision hemostatic model is respectively 0.5 g, 0.6 g and 1.1 g.

Therefore, in the embodiment 1, by increasing the dosage of the formylated glucan cross-linking agent, the extrusion resistance and the hemostatic performance of the material after imbibition and expansion are obviously improved, and the main purpose of increasing the dosage of the formylated glucan cross-linking agent is to improve the mechanical property of the material, and the hydrophilicity of the material is also obviously improved. Although the material of example 1 has reduced liquid absorption rate and liquid absorption expansion, the hemostatic performance is obviously improved, which indicates that the surface hydrophilicity of the composite hemostatic material has greater influence on the hemostatic performance of the material than the porosity and liquid absorption rate.

Example 3

The difference between the embodiment and the embodiment 1 is that the weight ratio of the prepared materials is 1788, the weight ratio of the polyvinyl alcohol, the sodium alginate, the 2, 3-epoxypropyl trimethyl ammonium chloride, the dextran, the glutaraldehyde, the hydrochloric acid and the sodium bicarbonate solution is 15:2.3:3.94:1.01:2.4:5:3.

The average pore diameter of the material was measured to be 27.64 μm at a 500 μm scale. The porosity of the composite hemostatic material is 77.95%, the liquid absorption rate is 1396%, the liquid absorption expansion degree is 5626%, and the compression strength is 222.69 Kpa.

Thus, in example 1, the liquid absorption rate and the liquid absorption expansion degree of the material are obviously improved by reducing the amount of 1788 type polyvinyl alcohol, and the main purpose of adding 1788 type polyvinyl alcohol is to improve the porosity and the mechanical property of the material, but too high amount of 1788 type polyvinyl alcohol can reduce the hydrophilicity of the material, and too high mechanical property can cause secondary injury to wounds.

Example 4

The difference between the embodiment and the embodiment 1 is that 40% glyoxal (after being used as medicine and analytically pure) is selected as an aldehyde modifier of dextran, the weight ratio of the prepared materials is 1788 type polyvinyl alcohol, sodium alginate, 2, 3-epoxypropyl trimethyl ammonium chloride, dextran, glyoxal, hydrochloric acid and sodium bicarbonate solution is 10:3:5.145:0.672:1.6:5:3.

The average pore diameter of the material was measured to be 27.9 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 3 s, and the contact angle of the material is 0 degree in three seconds. The porosity of the composite hemostatic material is 88.72%, the liquid absorption rate is 3660%, the liquid absorption expansion degree is 7880%, and the compression strength is 151.12 Kpa. The blood loss amounts of the composite hemostatic material in the rat liver cross incision hemostatic model, the rat liver standard disc-shaped loss hemostatic model and the rat femoral artery transverse incision hemostatic model are respectively 0.28 g, 0.55 g and 1.05 g. Thus, both glyoxal and glutaraldehyde can be used as aldehyde-based modifiers for dextran.

Comparative example 1

The difference between this comparative example and example 1 is that the cross-linking agent is glutaraldehyde.

The comparative example provides a composite hemostatic material for rapidly controlling non-compression hemorrhage, and the preparation method specifically comprises the following steps:

(1) 1788 polyvinyl alcohol (Bi De medical, purity is 1788), sodium alginate (Shanghai Ala chemical technology Co., ltd., viscosity is 200+ -20 mPa s), 2, 3-epoxypropyl trimethyl ammonium chloride (Shanghai Ala chemical technology Co., ltd. Gtoreq.95%), glutaraldehyde 50% (Du city Colon chemical Co., ltd., analytical grade), hydrochloric acid (Du city Colon chemical Co., purity is 20%), sodium bicarbonate (Shanghai Ala chemical technology Co., ltd., AR, > 99.8%);

(2) Weighing and preparing the raw materials, wherein the weight ratio of the raw materials is 1788, namely polyvinyl alcohol, sodium alginate, 2, 3-epoxypropyl trimethyl ammonium chloride, glutaraldehyde, hydrochloric acid and sodium bicarbonate solution is 10:3:5.145:1.6:5:3;

(6) Adding quaternized sodium alginate into the solution under stirring, and stirring and reacting for 1 hour at 50 ℃ at the rotating speed of 1200 rpm;

(7) Adding 8.25 ml hydrochloric acid into a 50ml volumetric flask, and adding deionized water for dilution to obtain hydrochloric acid with a mass fraction of 3.3%;

(8) Pouring the mixed solution into a beaker, standing to room temperature, gradually adding hydrochloric acid for acidification, and stirring and foaming for 1.5 hours at a rotating speed of 1800 rpm;

(9) Adding glutaraldehyde solution, and stirring thoroughly;

(10) Pouring the foam solution into a mould, rapidly forming the material, pre-freezing for 4 hours at-35 ℃, and freeze-drying the sample for 48 hours at-50 ℃ to obtain aerogel;

(11) Dissolving 4g sodium bicarbonate in deionized water, pouring into a 50ml volumetric flask for dilution, and obtaining sodium bicarbonate solution with the mass fraction of 7.75%;

(12) And (3) placing the aerogel into deionized water, washing for 1 hour, adding sodium bicarbonate solution to adjust the pH of the solution to 7-8, pre-freezing for 4 hours at the temperature of minus 35 ℃, and freeze-drying the sample for 24 hours at the temperature of minus 50 ℃ to finally obtain the composite hemostatic material.

The average pore diameter of the material was found to be 70.6 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 6.3 s, and the contact angle of the material is 59.7 degrees at three seconds. The porosity of the composite hemostatic material is 73.27%, the liquid absorption rate is 2210%, the liquid absorption expansion degree is 439.9%, and the compression strength is 88.56 Kpa. The blood loss amounts of the composite hemostatic material in the rat liver cross incision hemostatic model, the rat liver standard disc-shaped loss hemostatic model and the rat femoral artery transverse incision hemostatic model are respectively 0.4 g, 0.8 g and 1.9 g.

From this, in example 1, the extrusion resistance, water contact angle and hemostatic performance of the material after imbibition and expansion are all obviously improved by changing the cross-linking agent from small molecule glutaraldehyde to aldehyde dextran cross-linking agent, and the main purpose of changing the cross-linking agent to aldehyde dextran is to improve the mechanical properties of the material, but unexpectedly, the imbibition and expansion degree of the material is also obviously improved.

Comparative example 2

This comparative example differs from example 1 in that the composite hemostatic material does not contain glutaraldehyde-modified dextran cross-linking agents.

(1) Selecting 1788 type polyvinyl alcohol (Pichia medicine, purity is 1788), sodium alginate (Shanghai Ala chemical technology Co., ltd., viscosity is 200+ -20 mPa s), 2, 3-epoxypropyl trimethyl ammonium chloride (Shanghai Ala chemical technology Co., ltd. Gtoreq.95%), hydrochloric acid (Cheng Du-city Colon chemical Co., purity is 20%), sodium bicarbonate (Shanghai Ala chemical technology Co., ltd., AR. Gtoreq.99.8%);

(2) Weighing and preparing the raw materials, wherein the weight ratio of the raw materials is 1788, namely polyvinyl alcohol, sodium alginate, 2, 3-epoxypropyl trimethyl ammonium chloride, hydrochloric acid and sodium bicarbonate solution is 10:4.7:8.06:5:3;

(6) Adding quaternized sodium alginate into the solution under stirring, and stirring at a rotation speed of 1200 rpm at 50 ℃ for 1 hour;

(9) Pouring the foam solution into a mould, vacuum defoaming, pre-freezing for 4 hours at the temperature of minus 35 ℃, and freeze-drying the sample for 48 hours at the temperature of minus 50 ℃ to obtain the composite hemostatic material.

The average pore diameter of the material was measured to be 42.1 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 57.3 s, and the contact angle of the material is 103.77 degrees at three seconds. The porosity of the composite hemostatic material is 72.47%, and the liquid absorption rate is 1011.2%. After the composite hemostatic material of comparative example 2 absorbs water, the structure collapses, and the liquid absorption expansion degree and the compression strength cannot be measured.

Thus, in the embodiment 1 of the application, the extrusion resistance, the hydrophilic performance and the liquid absorption rate of the material after liquid absorption expansion are obviously improved by adding the aldehyde glucan cross-linking agent, and the main purpose of adding the aldehyde glucan cross-linking agent is to improve the mechanical property of the material, but the unexpected effect is that the liquid absorption expansion degree of the material is also obviously improved.

Comparative example 3

The comparative example differs from example 1 in that sodium alginate is used in the composite hemostatic material.

(1) Selecting 1788 type polyvinyl alcohol (Bi De medical, purity is 1788), sodium alginate (Shanghai Ala Latin Biotechnology Co., ltd., viscosity is 200+ -20 mPa s), dextran (Shanghai Michelin Biotechnology Co., ltd., molecular weight is 70000), glutaraldehyde 50% (Cheng Long chemical Co., ltd., analytical grade), hydrochloric acid (Cheng Long chemical Co., ltd., purity is 20%), sodium bicarbonate (Shanghai Ala Latin Biotechnology Co., ltd., AR, > 99.8%);

(2) Weighing and preparing materials, wherein the weight ratio of the materials is 1788, namely polyvinyl alcohol, sodium alginate, dextran, glutaraldehyde, hydrochloric acid and sodium bicarbonate solution is 10:3:0.672:1.6:5:3;

(3) Dissolving 1788 type polyvinyl alcohol in deionized water, and stirring for 2 hours at the temperature of 90 ℃ at the rotation speed of 1200 rpm;

(4) Adding 8.25 ml hydrochloric acid into a 50ml volumetric flask, and adding deionized water for dilution to obtain hydrochloric acid with a mass fraction of 3.3%;

(5) Dissolving glucan in deionized water, adding hydrochloric acid for acidification, adding glutaraldehyde solution for stirring reaction to obtain glutaraldehyde modified glucan;

(6) Mixing 1788 type polyvinyl alcohol solution and polyaldehyde dextran solution, stirring and mixing at 50deg.C;

(7) Adding sodium alginate into the solution (6) under stirring, and stirring and reacting for 1 hour at 50 ℃ at the rotating speed of 1200 rpm;

(9) Pouring the foam solution into a mould, vacuum defoaming, pre-freezing for 4 hours at-35 ℃, and freeze-drying the sample for 48 hours at-50 ℃;

(10) Dissolving 4 g sodium bicarbonate in deionized water, pouring into a 50 ml volumetric flask for dilution, and obtaining sodium bicarbonate solution with the mass fraction of 7.75%;

(11) And (3) putting the freeze-dried aerogel in the step (9) into deionized water, flushing for 1 hour, adding sodium bicarbonate solution to adjust the pH of the solution to 7-8, pre-freezing for 4 hours at the temperature of minus 35 ℃, and freeze-drying the sample for 24 hours at the temperature of minus 50 ℃ to finally obtain the composite hemostatic material for rapidly controlling non-compression bleeding.

The average pore diameter of the material was found to be 31.2 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 3 s, and the contact angle of the material is 0 degree in three seconds. The porosity of the composite hemostatic material is 80.1%, the liquid absorption rate is 3510%, the liquid absorption expansion degree is 7840%, and the compression strength is 140.12 Kpa. The blood loss amounts of the composite hemostatic material in the rat liver cross incision hemostatic model, the rat liver standard disc-shaped loss hemostatic model and the rat femoral artery transverse incision hemostatic model are respectively 0.5 g, 0.8 g and 1.6 g.

Therefore, in the embodiment 1 of the application, the sodium alginate grafted quaternary ammonium group has little influence on the liquid absorption swelling hydrophilicity and the liquid absorption rate of the material, but the hemostatic performance of the material is greatly improved. The quaternized sodium alginate has positive charges, so that the aggregation of red blood cells can be promoted, and the coagulation of wound surfaces can be promoted.

Comparative example 4

The comparative example differs from example 1 in that the hemostatic material matrix material is only quaternized sodium alginate.

(1) Sodium alginate (Shanghai Ala chemical Co., ltd., viscosity of 200+ -20 mPa s), 2, 3-epoxypropyl trimethyl ammonium chloride (Shanghai Ala chemical Co., ltd. Gtoreq.95%), dextran (Shanghai Michelin chemical Co., ltd., molecular weight of 70000), glutaraldehyde 50% (Cheng Long chemical Co., ltd., analytical grade), hydrochloric acid (Cheng Long chemical Co., ltd., purity of 20%), sodium bicarbonate (Shanghai Ala chemical Co., ltd., AR,. Gtoreq.99.8%);

(2) Weighing and preparing the raw materials, wherein the weight ratio of the sodium alginate to the 2, 3-epoxypropyl trimethyl ammonium chloride to the dextran to the glutaraldehyde to the hydrochloric acid to the sodium bicarbonate solution is 3:5.145:0.336:0.8:5:3;

(5) Dissolving quaternized sodium alginate in deionized water, and stirring for 1 hour at a rotation speed of 1200 rpm at 50 ℃;

(8) Mixing the quaternized sodium alginate solution with the polyaldehyde dextran solution, and stirring for 0.5h at 50 ℃;

(9) Pouring the mixed solution into a beaker, standing to room temperature, gradually adding hydrochloric acid for acidification, and stirring and foaming for 1.5 hours at a rotating speed of 1800 rpm;

(10) Pouring the foam solution into a mould, vacuum defoaming, pre-freezing for 4 hours at-35 ℃, and freeze-drying the sample for 48 hours at-50 ℃;

(12) And (3) putting the freeze-dried aerogel in the step (10) into deionized water, flushing for 1 hour, adding sodium bicarbonate solution to adjust the pH of the solution to 7-8, pre-freezing for 4 hours at the temperature of minus 35 ℃, and freeze-drying the sample for 24 hours at the temperature of minus 50 ℃ to finally obtain the composite hemostatic material for rapidly controlling non-compression bleeding.

The average pore diameter of the material was found to be 20.5 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 8 s, and the contact angle of the material is 53.2 degrees at three seconds. The porosity of the composite hemostatic material is 70.1%, the liquid absorption rate is 1510%, and the liquid absorption expansion degree is 840%.

From this, in example 1 of the present application, quaternized sodium alginate and 1788 polyvinyl alcohol were selected to form a composite hemostatic material, which imparts high porosity, high surface area and pore volume to the material. When the matrix is only quaternized sodium alginate, structural collapse occurs after the hemostatic material absorbs liquid, which indicates that 1788 type polyvinyl alcohol can be used as a framework structure to endow the material with good mechanical property, and the effect of supporting wound intelligent hemostasis is achieved.

Comparative example 5

The comparative example differs from example 1 in that the hemostatic material matrix is only 1788 type polyvinyl alcohol.

(1) 1788 Polyvinyl alcohol (Bi De medical, purity 1788), dextran (Shanghai Meilin Biochemical technology Co., ltd., molecular weight is 70000), glutaraldehyde 50% (Cheng Du Jiu Kelong Chemie Co., ltd., analytical grade), hydrochloric acid (Cheng Du Jiu Cheng Co., purity 20%), sodium bicarbonate (Shanghai Ala Ding Biochemical technology Co., ltd., AR, > 99.8%);

(2) Weighing and preparing the raw materials, wherein the weight ratio of the raw materials is 1788, namely, polyvinyl alcohol, dextran, glutaraldehyde, hydrochloric acid and sodium bicarbonate solution is 10:0.336:0.8:5:3;

(6) Mixing 1788 type polyvinyl alcohol solution and polyaldehyde dextran solution, stirring and mixing at 50deg.C for 0.5h;

(7) Pouring the mixed solution into a beaker, standing to room temperature, gradually adding hydrochloric acid for acidification, and stirring and foaming for 1.5 hours at a rotating speed of 1800 rpm;

(8) Pouring the foam solution into a mould, vacuum defoaming, pre-freezing for 4 hours at-35 ℃, and freeze-drying the sample for 48 hours at-50 ℃;

(9) Dissolving 4 g sodium bicarbonate in deionized water, pouring into a 50 ml volumetric flask for dilution, and obtaining sodium bicarbonate solution with the mass fraction of 7.75%;

(10) And (3) putting the freeze-dried aerogel in the step (8) into deionized water, flushing for 1 hour, adding sodium bicarbonate solution to adjust the pH of the solution to 7-8, pre-freezing for 4 hours at the temperature of minus 35 ℃, and freeze-drying the sample for 24 hours at the temperature of minus 50 ℃ to finally obtain the composite hemostatic material for rapidly controlling non-compression bleeding.

The average pore diameter of the material was found to be 45.1 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 60 s, and the contact angle of the material is 62.2 degrees at three seconds. The porosity of the composite hemostatic material is 80.1%, the liquid absorption rate is 612%, and the liquid absorption expansion degree is 125%.

From this, in the embodiment 1 of the present application, the quaternized sodium alginate and 1788 polyvinyl alcohol are selected to form the composite hemostatic material, and the composite hemostatic material has the flexible structure, high hydrophilicity and high hemostatic performance. When the matrix is 1788 type polyvinyl alcohol, the hemostatic material is of a rigid structure, and the liquid absorption is poor, so that the quaternized sodium alginate can not only endow the material with good hemostatic and antibacterial capabilities, but also can be mutually blended with 1788 type polyvinyl alcohol, and the intelligent hemostatic effect of supporting a wound and preventing secondary injury to the wound is achieved.

Comparative example 6

This comparative example differs from example 1 in that the washing with water and alkali neutralization steps were omitted and the material that was not washed with water and alkali neutralization was directly used as the hemostatic material.

(1) 1788 polyvinyl alcohol (Bi De medical, purity 1788), sodium alginate (Shanghai Ala Biochemical technology Co., ltd., viscosity 200+ -20 mPa s), 2, 3-epoxypropyl trimethyl ammonium chloride (Shanghai Ala Biochemical technology Co., ltd. Gtoreq.95%), dextran (Shanghai Michelin Biochemical technology Co., ltd., average molecular weight 70000), glutaraldehyde 50% (Cheng Long chemical Co., analytical grade, cheng Long chemical Co., ltd., purity 20%) and hydrochloric acid (Cheng Long chemical Co., ltd.);

(2) Weighing and preparing materials, wherein the weight ratio of the materials is 1788, namely polyvinyl alcohol, sodium alginate, 2, 3-epoxypropyl trimethyl ammonium chloride, dextran, glutaraldehyde and hydrochloric acid is 15:4.5:7.72:1.01:2.4:5;

(7) Dissolving glucan in deionized water, adding hydrochloric acid for acidification, adding glutaraldehyde solution, and stirring for reaction to obtain dialdehyde modified polyaldehyde glucan;

(11) Pouring the foam solution into a mould, vacuum defoaming, pre-freezing for 4 hours at the temperature of minus 35 ℃, and freeze-drying the sample for 48 hours at the temperature of minus 50 ℃ to finally obtain the composite hemostatic material for rapidly controlling non-compression bleeding.

The average pore diameter of the material was found to be 32.8 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 4 s, and the contact angle of the material is 32.2 degrees at three seconds. The porosity of the composite hemostatic material is 60.17%, the liquid absorption rate is 2080%, the liquid absorption expansion degree is 6021%, and the compression strength is 186.34 Kpa. The blood loss amounts of the composite hemostatic material in the rat liver cross incision hemostatic model, the rat liver standard disc-shaped loss hemostatic model and the rat femoral artery transverse incision hemostatic model are respectively 0.62 g, 0.76 g and 1.5 g.

Therefore, if the material which is not washed and neutralized by alkali is directly used as the hemostatic material without the step of the invention, the unreacted material in the material can block pore channels and further influence capillary phenomenon and liquid diffusion, meanwhile, the acidic environment can have great negative influence on the hemostatic performance of the material, the porosity, the liquid absorption rate and the hydrophilicity of the material are reduced, and the liquid absorption expansion degree and the hemostatic performance of the material are obviously reduced.

Comparative example 7

The difference between the embodiment and the embodiment 1 is that the weight ratio of the prepared materials is 1788 polyvinyl alcohol, sodium alginate, 2, 3-epoxypropyl trimethyl ammonium chloride, dextran (molecular weight is 10000), glutaraldehyde, hydrochloric acid and sodium bicarbonate solution is 15:4.5:7.72:1.01:2.4:5:3.

The average pore diameter of the material was found to be 32.62 μm at a 500 μm scale. The residence time of the liquid drop on the surface of the composite hemostatic material is 4 s, and the contact angle of the material is 59.59 degrees at three seconds. The porosity of the composite hemostatic material is 86.48%, the liquid absorption rate is 3521%, the liquid absorption expansion degree is 5692%, and the compression strength is 131.4 Kpa.

From this, it can be seen that in example 1, by increasing the molecular weight of the formylated dextran cross-linking agent, although the porosity and the liquid absorption rate of the material are not greatly changed, the liquid absorption expansion degree and the hydrophilicity are both obviously improved, the molecular weight of the cross-linking agent directly affects the hydrophilicity and the liquid absorption expansion degree of the composite hemostatic material, and the liquid absorption expansion degree and the hydrophilicity of the material can be obviously enhanced by selecting the molecular weight of the formylated dextran cross-linking agent in the scheme of the invention.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a composite hemostatic material for rapidly controlling non-compression bleeding, comprising the steps of:

2. The method for preparing the composite hemostatic material for rapidly controlling non-compression hemorrhage according to claim 1, wherein in the step S1, the mass ratio of the sodium alginate to the 2, 3-epoxypropyl trimethyl ammonium chloride is (2-8): 3-8.

3. The method for preparing a composite hemostatic material for rapidly controlling non-compression hemorrhage according to claim 1, wherein in the step S3, the mass ratio of the dextran to the hydroformylation modifier is (0.5-3.5) (0.5-1.6).

4. The method for preparing a composite hemostatic material for rapidly controlling non-compression bleeding according to claim 1, wherein in step S1, the pH is equal to or less than 7.

5. The method for preparing a composite hemostatic material for rapidly controlling non-compression hemorrhage according to claim 1, wherein in step S6, the pH value is 7-8.

6. The method for preparing a composite hemostatic material for rapidly controlling non-compression hemorrhage according to claim 1, wherein in step S3, the molecular weight of glucose in the aqueous dextran solution is 60000-80000.

7. The method for preparing a composite hemostatic material for rapidly controlling non-compression bleeding according to claim 1, wherein in the step S3, the acidification treatment is performed with 3.3% by mass of hydrochloric acid.

8. The method of preparing a composite hemostatic material for rapidly controlling non-compression bleeding according to any one of claims 1 to 7, wherein the hydroformylation modifier comprises at least one of glutaraldehyde and glyoxal.

9. The method for preparing the composite hemostatic material for rapidly controlling non-compression bleeding according to claim 1, wherein in the step S5, the first stage treatment temperature of vacuum defoaming is-35 to-20 ℃, the treatment time is 2-4 hours, the second stage treatment temperature is-50 to 0 ℃, and the treatment time is 24-48 hours.

10. The composite hemostatic material prepared by the preparation method of any one of claims 1-9 is characterized by comprising, by weight, 1-10 parts of quaternized sodium alginate, 10-15 parts of 1788-type polyvinyl alcohol and 0.1-5 parts of aldehyde modified glucan.