CN109908396B

CN109908396B - Calcium ion exchange porous starch hemostatic material and preparation method and application thereof

Info

Publication number: CN109908396B
Application number: CN201910015590.8A
Authority: CN
Inventors: 朱建军; 窦桂芳; 孙文种; 孟志云; 朱晓霞; 甘慧; 顾若兰; 吴卓娜
Original assignee: Academy of Military Medical Sciences AMMS of PLA
Current assignee: Academy of Military Medical Sciences AMMS of PLA
Priority date: 2019-01-08
Filing date: 2019-01-08
Publication date: 2021-11-02
Anticipated expiration: 2039-01-08
Also published as: CN114099763A; CN109908396A

Abstract

The invention relates to a calcium ion exchange porous starch hemostatic material, a preparation method and application thereof. The calcium ion exchange porous starch hemostatic material is prepared by starch through gelatinization, emulsification, pore-forming, crosslinking and calcium ion exchange, and comprises the following raw materials: starch, an oil phase, a pore-forming agent, an emulsifier, calcium chloride, a cross-linking agent and the balance of water. The hemostatic material is subjected to pore forming by an ethanol-alkali method to increase the specific surface area, crosslinking reaction to increase the structural stability, reverse microemulsion method technology to control the particle size distribution, and calcium ion modification on the surface, so that the hemostatic performance, degradation performance and biocompatibility of the hemostatic material are enhanced. The calcium ion exchange porous starch hemostatic material provided by the invention has the advantages of abundant main raw material sources, good safety and no residue, can be widely applied to hemostasis of irregular bleeding such as parenchymal viscera in vivo and diffuse bleeding, does not need debridement after hemostasis, and can be degraded and absorbed by a human body after the hemostasis effect is continued to an operation.

Description

Calcium ion exchange porous starch hemostatic material and preparation method and application thereof

Technical Field

The invention relates to the technical field of biomedical materials, in particular to a calcium ion exchange porous starch hemostatic material and a preparation method and application thereof.

Background

Although the hemostasis technology in the operation is continuously improved in recent years, the existing hemostasis technology and hemostasis material still have defects for irregular bleeding and other diffuse bleeding of parenchymal organs in and after the operation of patients with blood coagulation dysfunction. The advent of some absorbable hemostatic materials, such as fibrin glues, oxidized regenerated celluloses, and microporous polysaccharides, has addressed some of the above problems, but has the following drawbacks:

fibrin glue absorbable hemostatic material, which is derived from plasma of animals or human bodies, has good hemostatic effect in liver and kidney injury models of some patients with blood coagulation dysfunction, but is expensive and has the problems of foreign body rejection, immunogenicity and the like (Fukushima et al, 2018).

The oxidized regenerated cellulose absorbable hemostatic material is prepared by selectively oxidizing the hydroxyl of cellulose. Although there are many different types of absorbable hemostatic materials on the market today, oxidized regenerated cellulose, their in vivo degradation and absorption effect is still not ideal (Fukuzumi et al, 2011; Hutchinson et al, 2013).

The microporous polysaccharide absorbable hemostatic material, such as Arista AH absorbable hemostatic particles marketed in the United states and Xin Su absorbable hemostatic particles marketed in China, does not contain any animal-derived or human-derived components, and can avoid the risk of allergy. In addition, Arista AH particles absorb liquid and swell rapidly, after absorbing water in blood, solid components in the blood are concentrated, the concentration of blood coagulation factors near a bleeding point is increased, and a blood coagulation cascade reaction is activated to achieve the aim of stopping bleeding. Since Arista AH contains starch as main ingredient, it can be degraded by amylase in vivo, and can be completely absorbed in 7-14 days. Therefore, Arista AH has gradually become one of the necessary new absorbable hemostatic materials in domestic and foreign operations. However, Arista AH is a small pig liver injury model with blood coagulation dysfunction, and has no chemical hemostasis mechanism (Murat et al, 2006) because it is merely dependent on physical hemostasis by absorbing water in blood and self-swelling, and thus has poor effect on hemostasis of major arteriovenous hemorrhage and hemorrhage of patients with blood coagulation dysfunction.

The porous starch hemostatic material is one of microporous polysaccharides, is prepared by pore-forming methods such as physical, chemical or enzymolysis by using starch as a raw material, and has porous structures on the surface and inside of particles. The key point of the starch hemostatic material in playing the hemostatic effect is that the surface of the starch hemostatic material has a porous structure, and the porous structure plays the following roles: firstly, the contact area of the hemostatic material and water molecules can be increased, and the liquid absorption rate of the hemostatic material is increased; secondly, small molecular substances are favorably adsorbed on the surface of the hemostatic material, and the blood coagulation cascade reaction is accelerated; and thirdly, the degradation rate of the hemostatic material in a human body by amylase is accelerated, so that the hemostatic material is rapidly degraded and absorbed, and the biocompatibility of the hemostatic material is improved.

Therefore, the hemostatic effect of starch hemostatic materials is greatly influenced by the surface porous structure morphology, which depends on the pore-forming method and the parameter conditions thereof. At present, the pore-forming method of the starch hemostatic material mainly comprises a physical pore-forming method, a chemical pore-forming method and an enzymatic pore-forming method; wherein, the porous starch prepared by the physical pore-forming method has large dependence on equipment and high cost. The porous starch prepared by the chemical pore-forming method has the problems of fragile pores, insufficient particle uniformity and the like. The porous starch prepared by the enzymolysis pore-forming method has the defects of long reaction time, high cost, harsh reaction conditions, difficult separation and the like.

Disclosure of Invention

The invention aims to overcome the technical defects in the prior art, and provides a calcium ion exchange porous starch hemostatic material which has a good hemostatic effect and is quickly degraded and absorbed in vivo on the first aspect, wherein the calcium ion exchange porous starch hemostatic material is prepared by starch through gelatinization, emulsification, pore-forming, crosslinking and calcium ion exchange, and the raw materials comprise the following components in percentage by mass:

the volume of the emulsifier is 0.1-1.5%, preferably 0.5-1.0% of the volume of the oil phase.

The volume ratio of the total volume of the mixed emulsifier and oil phase to the gelatinized starch solution after gelatinization is (0.5-8):1, preferably (1-4): 1.

the pore-forming agent is selected from one or more of polyethylene glycol, ethanol, methanol and the like.

The starch is selected from one or more of potato starch, sweet potato starch, cassava starch, corn starch, mung bean starch, water chestnut starch, lotus root starch, wheat starch and the like; and/or

The oil phase is selected from one or more of cyclohexane-chloroform mixture, liquid paraffin, soybean oil, etc.; and/or

The emulsifier is selected from one or more of span80, span60, tween 20 and the like.

The invention provides a method for preparing the calcium ion exchange porous starch hemostatic material with low production cost, which comprises the steps of gelatinizing starch; emulsifying, pore-forming and crosslinking the gelatinized starch solution; and (3) performing calcium ion exchange after the crosslinking is finished, preferably, adding a saturated calcium chloride solution into the reaction solution after the crosslinking, and filtering to obtain a solid, namely the calcium ion exchange porous starch hemostatic material.

Emulsifying, pore-forming and crosslinking the gelatinized starch solution, namely mixing an emulsifier and an oil phase to prepare an emulsifier solution, adding the gelatinized starch solution into the emulsifier solution, stirring for emulsifying, adding a pore-forming agent after emulsifying, stirring for pore-forming, and then adding a crosslinking agent for crosslinking; preferably, the stirring speed during emulsification is 200-1000 rpm.

The volume of the emulsifier is 0.1-1.5% (preferably 0.5-1.0%) of the volume of the oil phase; and/or

The volume ratio of the emulsifier solution to the gelatinized starch solution is (0.5-8) to 1 (preferably (1-4) to 1); and/or

The stirring speed during pore-forming is 200-1000rpm, and the stirring time is 5-20 min.

The emulsification, pore-forming and crosslinking of the gelatinized starch solution are specifically as follows: adding the emulsifier into the oil phase, and stirring until the emulsifier is uniformly mixed with the oil phase to obtain an emulsifier solution; heating the emulsifier solvent to 40-60 ℃, adding the gelatinized starch solution into the emulsifier solution, emulsifying at 200-1000rpm, adding the pore-forming agent, stirring at 200-1000rpm for 5-20min, and adding the cross-linking agent for cross-linking reaction for 2-8 h.

The gelatinization of the starch specifically comprises the following steps: adding water into starch to prepare a starch water solution with the starch concentration of 2-10 wt%, heating at 50-300rpm and 45-65 ℃ for 1-10min, cooling to 20-30 ℃, and adjusting the pH to 9.0-11.0 to obtain a gelatinized starch solution.

In a third aspect, the invention provides the use of the calcium ion-exchange porous starch hemostatic material in the preparation of a hemostatic agent for bleeding from a complicated wound and/or bleeding from a patient with blood coagulation dysfunction; preferably, the complicated wound bleeding is in vivo parenchymal organ bleeding, diffuse capillary vessel bleeding, inflammation, fragile tissue bleeding and the like; or

Preferably, the particle size of the calcium ion-exchange porous starch hemostatic material is 50-1500 μm, the water absorption volume in 30s per 100mg of the hemostatic material is 0.2-1.2ml (preferably 0.5-1.2ml), and the calcium ion content is 0.1-15 mg/g.

The calcium ion exchange porous starch hemostatic material provided by the invention is a hemostatic agent which can be applied to bleeding of complex wounds such as parenchymal viscera in operation, or bleeding of large arteriovenous in wartime and civil emergency. The main raw material of the hemostatic material is starch, the source is rich, the hemostatic material is safe and nontoxic, the starch is treated by ethanol-alkali method, reverse microemulsion method, crosslinking reaction, calcium ion exchange and other steps, the surface is full of particles, the interior is rough and porous, the specific surface area of the hemostatic material is obviously increased, the contact area of water molecules and the hemostatic material is increased, the hemostatic material is favorable for adsorbing the water molecules, and the water molecule adsorption capacity of the hemostatic material is obviously increased; the hemostatic material provided by the invention has a hole structure inside, and is beneficial to transfer of water molecules inside the hemostatic material, so that the capability of the hemostatic material for transferring water molecules in blood is enhanced. Meanwhile, the hemostatic material provided by the invention has a porous surface, so that the adsorption capacity with amylase can be increased, the hemostatic material is favorable for contacting with starch degrading enzymes such as amylase in vivo, and the rapid degradation of the hemostatic material in vivo is effectively promoted. Calcium ions are the only inorganic blood coagulation factor, can promote the internal and external source blood coagulation system and promote the formation of fibrin, and the calcium ion exchange porous starch hemostatic material is released into blood, can obviously promote the internal and external source blood coagulation cascade reaction, platelet adhesion and other blood coagulation processes, and utilizes a chemical hemostatic mechanism to perform hemostasis. The hemostatic effect of the hemostatic material can be continued after operation, the hemostatic material can be degraded and absorbed by a human body after the operation, and debridement is not needed after hemostasis, so that secondary injury to a wound is avoided, and the wound is prevented from bleeding again after debridement.

The calcium ion exchange porous starch hemostatic material provided by the invention has the advantages of good biocompatibility, no cytotoxicity, no sensitization reaction and acute toxicity, large specific surface area, high liquid absorption rate and quick swelling, and is a starch hemostatic material with excellent hemostatic effect and good safety. The porous starch hemostatic material is prepared by an ethanol-alkali method, so that starch particles with particle surfaces and porous structures can be obtained, the post-treatment in the preparation process is simple, the starch particles are washed by ethyl acetate and absolute ethyl alcohol and then filtered and dried, and the obtained hemostatic material is high in purity and free of impurities.

Drawings

FIG. 1 is an external view of a calcium ion-exchanged porous starch hemostatic material of the present invention;

FIG. 2 is a bar graph showing the metal ion content of the calcium ion-exchanged porous starch hemostatic materials of examples 1 and 7;

FIG. 3 is a graph showing the PBS imbibition rate of the calcium ion-exchanged porous starch hemostatic material of example 7;

FIG. 4 is a graph showing the particle size distribution of the calcium ion-exchanged porous starch hemostatic material of example 7;

FIG. 5 is a microstructure view of a calcium ion-exchanged porous starch hemostatic material of the present invention;

FIG. 6 is a graph showing the in vitro whole blood coagulation kinetics of the calcium ion-exchanged porous starch hemostatic materials of example 1 and example 7;

FIG. 7 is a bar graph showing the cytotoxicity of the calcium ion-exchanged porous starch hemostatic material of example 7;

FIG. 8 is a bar chart showing the amount and effect of hemostasis of the calcium ion-exchanged porous starch hemostatic material of example 7 when applied to mice after cauda amputation.

Detailed Description

The calcium ion exchange porous starch hemostatic material provided by the invention comprises the following raw materials in percentage by mass:

wherein the starch can be one or more selected from potato starch, sweet potato starch, tapioca starch, corn starch, mung bean starch, water caltrop starch, lotus root starch, wheat starch, etc.; the oil phase can be one or more selected from cyclohexane-chloroform mixture, liquid paraffin, soybean oil, etc.; the emulsifier can be one or more selected from span80, span60, tween 20 and the like; the pore-forming agent can be one or more selected from polyethylene glycol, ethanol, methanol, etc.

The calcium ion exchange porous starch hemostatic material is subjected to a large number of experimental screening on composition selection and raw material content, and the formula is finally obtained, so that the prepared hemostatic material can form starch particles with a proper particle size distribution range and particle size, and the quick liquid absorption performance of the hemostatic material is ensured. During the screening experiments, the inventors found that:

in the prepared calcium ion exchange porous starch hemostatic material, if the mass percentage of the oil phase is lower than 15%, calcium ion exchange porous starch hemostatic material particles with proper particle size and particle size distribution range cannot be formed, and if the mass percentage of the oil phase is higher than 87%, the liquid absorption rate of the calcium ion exchange porous cross-linked starch hemostatic material is low, so that rapid hemostasis cannot be realized.

The invention also provides a method for preparing the calcium ion exchange porous starch hemostatic material, which comprises the following steps:

1) pasting: adding water into starch to prepare a starch aqueous solution with the starch concentration of 2-10 wt%, mechanically stirring at the rotating speed of 50-300rpm, heating in a water bath kettle at the temperature of 45-65 ℃ for 1-10min, cooling to 20-30 ℃, cooling, and adjusting the pH to 9.0-11.0 by using a NaOH solution while stirring to obtain a gelatinized starch solution.

2) Emulsification, pore-forming and crosslinking: adding an emulsifier into an oil phase, mechanically stirring for 2-20min until the emulsifier and the oil phase are uniformly mixed to obtain an emulsifier solution, putting the emulsifier solvent into a water bath and heating to 40-60 ℃, slowly adding the gelatinized starch solution obtained in the step 1) into the emulsifier solution, emulsifying at the rotating speed of 200-1000rpm, adding a pore-forming agent after the gelatinized starch solution and the emulsifier solution are emulsified, mechanically stirring at the rotating speed of 200-1000rpm for 5-20min, adding a cross-linking agent, and continuously mechanically stirring for carrying out a cross-linking reaction for 2-8 h. Wherein the volume of the emulsifier is 0.1-1.5% of the volume of the oil phase, and the volume ratio of the emulsifier solution to the gelatinized starch solution is (0.5-8): 1.

3) Calcium ion exchange: after the crosslinking reaction is finished, adding a saturated calcium chloride solution into the reaction liquid obtained in the step 2) dropwise under mechanical stirring in a water bath at 40 ℃, reacting for 0.5-4h, filtering, washing the precipitate with ethyl acetate and absolute ethyl alcohol for 3 times respectively, filtering to obtain white particles, drying in an oven at 60 ℃ for 8h to obtain white powder, wherein the white powder is shown in figure 1, namely the calcium ion exchange porous starch hemostatic material, Co, of the invention⁶⁰Sterilizing, sealing and storing for later use.

The particle size of the calcium ion exchange porous starch hemostatic material is 50-1500 mu m, and observation under a scanning electron microscope shows that the calcium ion exchange porous starch hemostatic material is granular, the surface of the granules is rough and uneven, the surface and the inside of the granules are rough and porous, and the porous structures are different in size, so that the specific surface area of the hemostatic material is obviously increased, as shown in figure 5, the water absorption volume of each 100mg of the hemostatic material within 30s is 0.2-1.2ml, and the content of calcium ions is 0.1-15 mg/g.

The preparation method disclosed by the invention is screened out through a large number of experiments, in the process of preparing the porous starch hemostatic material, an ethanol-base method, a reverse microemulsion method and a crosslinking reaction are combined for the first time, the starch hemostatic material with rough and porous surface is prepared by using the ethanol-base method, and the particle size distribution range of the starch hemostatic material are controlled by using the reverse microemulsion method; secondly, when ethanol is selected as a pore-foaming agent, the addition amount of the ethanol is critical, the particle surface porous structure is small, the roughness is low, the specific surface area is small, and only in the range of the method, the roughness of the surface of the obtained starch particle reaches a peak value, and the liquid absorption rate also reaches a peak value; finally, the invention exchanges calcium ions into the porous starch for the first time, not only exerts physical hemostasis of the starch, but also exerts chemical hemostasis of the calcium ions, forms firm blood clots and better exerts the hemostasis effect.

The principle of ethanol alkaline method pore-forming is as follows: starch is gelatinized in an alkaline environment, a crystalline structure is damaged along with the gradual water absorption and swelling of the starch, and meanwhile, hydroxyl in a molecular chain of the starch is negatively charged due to the loss of hydrogen atoms in the alkaline environment. The chains of negatively charged starch molecules repel each other, further promoting swelling of the starch molecules. After the gelatinized starch is added with the pore-forming agent ethanol, as the starch is insoluble in absolute ethanol, the absolute ethanol is added instantly at the pore-forming stage, so that starch molecules are separated out quickly. Under the action of the instantaneous swelling and precipitation, the surface of the starch granules has an uneven porous structure.

The reverse microemulsion method is a method of forming water-in-oil droplets by oil phase and water phase under the action of an emulsifier under the condition of ultrasonic or mechanical stirring. The inverse phase means that the droplets formed are of the water-in-oil type, corresponding to the oil-in-water type. For the invention, the gelatinized starch solution is a water phase, and the oil phase wraps the gelatinized starch solution into water-in-oil type droplets under the action of an emulsifier.

The present invention will be described more specifically and further illustrated with reference to specific examples, which are by no means intended to limit the scope of the present invention.

Example 1

1) Pasting: adding 10g of corn starch into 500g of water to obtain a starch aqueous solution with the concentration of 2wt%, mechanically stirring at the rotating speed of 50rpm, heating at 45 ℃ for 1min, cooling to 20 ℃, and adding a NaOH solution to adjust the pH value of the starch aqueous solution to 9.0 to obtain a gelatinized starch solution.

2) Emulsification, pore-forming and crosslinking: adding 3g of emulsifier Span80 (Span 80) into 250mL of liquid paraffin, stirring for 10min until the two are uniformly mixed, heating to 45 ℃, then slowly adding 500mL of gelatinized starch solution obtained in the step 1), emulsifying at the rotating speed of 500rpm, adding 10mL of absolute ethyl alcohol after the gelatinized starch solution and the emulsifier solution are emulsified, mechanically stirring at the rotating speed of 500rpm for 15min, adding 0.5mL of epoxy chloropropane, and stirring for 2h to generate a crosslinking reaction.

3) Calcium ion exchange: after the crosslinking reaction is finished, 0.2mL of saturated calcium chloride solution is dropwise added under mechanical stirring at 40 ℃ for reaction for 2.5 hours, after the reaction is finished, ethyl acetate and absolute ethyl alcohol are respectively used for extraction for 3 times, and the mixture is dried in a drying oven at 60 ℃ for 8 hours to obtain a white granular hemostatic material, namely Co, of the invention⁶⁰Sterilizing, sealing and storing for later use.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 50-200 mu m, the water absorption volume of 100mg of the calcium ion exchange porous starch hemostatic material in 30s is 0.5mL, and the content of calcium ions is as follows: 0.1-1 mg/g.

Example 2

1) Pasting: adding 2g of potato starch into 100g of water to obtain a starch aqueous solution with the concentration of 2wt%, mechanically stirring at the rotating speed of 100rpm, heating at 65 ℃ for 5min, cooling to 30 ℃, adding a NaOH solution to adjust the pH value of the starch aqueous solution to 9.0, and obtaining a gelatinized starch solution.

2) Emulsification, pore-forming and crosslinking: adding 1.6g of emulsifier Span60 (Span 60) into 200mL of soybean oil, stirring for 5min until the two are uniformly mixed, heating to 50 ℃, then slowly adding 100mL of gelatinized starch solution obtained in the step 1), emulsifying at the rotating speed of 1000rpm, adding 50mL of polyethylene glycol after the gelatinized starch solution and the emulsifier solution are emulsified, mechanically stirring at the rotating speed of 1000rpm for 20min, adding 0.5mL of epoxy chloropropane, and stirring for 4h to generate a crosslinking reaction.

3) Calcium ion exchange: after the crosslinking reaction is finished, 10mL of saturated calcium chloride solution is dropwise added under mechanical stirring at 40 ℃ for reaction for 2 hours, after the reaction is finished, ethyl acetate and absolute ethyl alcohol are respectively used for extraction for 3 times, and drying is carried out in a drying oven at 60 ℃ for 8 hours to obtain a white granular hemostatic material, namely Co⁶⁰Sterilizing, sealing and storing for later use.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 50-500 mu m, the water absorption volume of 100mg of the calcium ion exchange porous starch hemostatic material in 30s is 0.7mL, and the content of calcium ions is as follows: 1-10 mg/g.

Example 3

1) Pasting: adding 10g of sweet potato starch into 200g of water to obtain a starch aqueous solution with the concentration of 5wt%, mechanically stirring at the rotating speed of 150rpm, heating at 60 ℃ for 3min, cooling to 30 ℃, and adding a NaOH solution to adjust the pH value of the starch aqueous solution to 10.0 to obtain a gelatinized starch solution.

2) Emulsification, pore-forming and crosslinking: adding 12g of emulsifier Span60 into 800mL of soybean oil, stirring for 15min until the two are uniformly mixed, heating to 60 ℃, then slowly adding 200mL of gelatinized starch solution obtained in the step 1), emulsifying at the rotating speed of 600rpm, adding 200mL of methanol after the gelatinized starch solution and the emulsifier solution are emulsified, mechanically stirring at the rotating speed of 600rpm for 15min, adding 8.0mL of epoxy chloropropane, and stirring for 8h to generate a crosslinking reaction.

3) Calcium ion exchange: after the crosslinking reaction is finished, dropwise adding 0.2mL of saturated calcium chloride solution under mechanical stirring at 40 ℃, reacting for 4h, after the reaction is finished, respectively extracting for 3 times by using ethyl acetate and absolute ethyl alcohol, and drying in a 60 ℃ oven for 8h to obtain a white granular hemostatic material, namely Co, a white granular hemostatic material of the invention⁶⁰Sterilizing, sealing and storing for later use.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 50-200 mu m, the water absorption volume of 100mg of the calcium ion exchange porous starch hemostatic material in 30s is 0.9mL, and the content of calcium ions is as follows: 0.1-1 mg/g.

Example 4

1) Pasting: adding 5g of potato starch into 50g of water to obtain a starch aqueous solution with the concentration of 10wt%, mechanically stirring at the rotating speed of 200rpm, heating at 55 ℃ for 7min, cooling to 20 ℃, and adding a NaOH solution to adjust the pH value of the starch aqueous solution to 10.0 to obtain a gelatinized starch solution.

2) Emulsification, pore-forming and crosslinking: adding 3g of emulsifier Span80 into 300mL of cyclohexane-chloroform mixture, stirring for 18min until the two are uniformly mixed, heating to 55 ℃, then slowly adding 50mL of gelatinized starch solution obtained in the step 1), emulsifying at the rotating speed of 800rpm, adding 50mL of methanol after the gelatinized starch solution and the emulsifier solution are emulsified, mechanically stirring at the rotating speed of 800rpm for 10min, adding 8.0mL of epoxy chloropropane, and stirring for 5h to generate a crosslinking reaction.

3) Calcium ion exchange: after the crosslinking reaction is finished, dropwise adding 1mL of saturated calcium chloride solution under mechanical stirring at 40 ℃, reacting for 0.5h, after the reaction is finished, respectively extracting for 3 times by using ethyl acetate and absolute ethyl alcohol, and drying in a 60 ℃ drying oven for 8h to obtain a white granular hemostatic material, namely Co⁶⁰Sterilizing, sealing and storing for later use.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 500-: 0.1-1 mg/g.

Example 5

1) Pasting: adding 10g of cassava starch into 100g of water to obtain a starch aqueous solution with the concentration of 10wt%, mechanically stirring at the rotating speed of 250rpm, heating at 50 ℃ for 10min, cooling to 30 ℃, adding a NaOH solution to adjust the pH value of the starch aqueous solution to 11.0, and obtaining a gelatinized starch solution.

2) Emulsification, pore-forming and crosslinking: adding 4g of emulsifier Span80 into 800mL of cyclohexane-chloroform mixture, stirring for 20min until the two are uniformly mixed, heating to 40 ℃, then slowly adding 100mL of gelatinized starch solution obtained in the step 1), emulsifying at the rotating speed of 400rpm, adding 50mL of polyethylene glycol after the gelatinized starch solution and the emulsifier solution are emulsified, mechanically stirring at the rotating speed of 400rpm for 5min, adding 8.0mL of epoxy chloropropane, and stirring for 2h to generate a crosslinking reaction.

3) Calcium ion exchange: after the crosslinking reaction is finished, 10mL of saturated calcium chloride solution is dropwise added under mechanical stirring at 40 ℃ to react for 1.5h, after the reaction is finished, ethyl acetate and absolute ethyl alcohol are respectively used for extraction for 3 times, and the mixture is dried in a 60 ℃ drying oven for 8h to obtain a white granular hemostatic material, namely Co⁶⁰Sterilizing, sealing and storing for later use.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 50-150 mu m, the water absorption volume of 100mg of the calcium ion exchange porous starch hemostatic material in 30s is 0.5mL, and the content of calcium ions is as follows: 1-10 mg/g.

Example 6

1) Pasting: adding 20g of lotus root starch into 200g of water to obtain a starch aqueous solution with the concentration of 10wt%, mechanically stirring at the rotating speed of 300rpm, heating at 65 ℃ for 9min, cooling to 30 ℃, and adding a NaOH solution to adjust the pH value of the starch aqueous solution to 11.0 to obtain a gelatinized starch solution.

2) Emulsification, pore-forming and crosslinking: adding 0.2g of emulsifier Tween 20 into 200mL of cyclohexane-chloroform mixture, stirring for 2min until the two are uniformly mixed, heating to 40 ℃, then slowly adding 200mL of gelatinized starch solution obtained in the step 1), emulsifying at the rotating speed of 200rpm, adding 200mL of polyethylene glycol after the gelatinized starch solution and the emulsifier solution are emulsified, mechanically stirring at the rotating speed of 200rpm for 10min, adding 0.2mL of epoxy chloropropane, and stirring for 3h to generate a crosslinking reaction.

3) Calcium ion exchange: after the crosslinking reaction is finished, dropwise adding 1mL of saturated calcium chloride solution under mechanical stirring at 40 ℃, reacting for 3.5h, after the reaction is finished, respectively extracting for 3 times by using ethyl acetate and absolute ethyl alcohol, and drying for 8h in a 60 ℃ drying oven to obtain a white granular hemostatic material, namely Co⁶⁰Sterilizing, sealing and storing for later use.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 800-: 1-10 mg/g.

Example 7

1) Pasting: adding 10g of potato starch into 200g of water to obtain a starch aqueous solution with the concentration of 5wt%, mechanically stirring at the rotating speed of 300rpm, heating at 65 ℃ for 10min, cooling to 30 ℃, and adding a NaOH solution to adjust the pH value of the starch aqueous solution to 11.0 to obtain a gelatinized starch solution.

2) Emulsification, pore-forming and crosslinking: adding 3.2g of emulsifier span80 into 400mL of liquid paraffin, stirring for 2min until the two are uniformly mixed, heating to 60 ℃, then slowly adding 200mL of gelatinized starch solution obtained in the step 1), emulsifying at the rotating speed of 500rpm, adding 200mL of absolute ethyl alcohol after the gelatinized starch solution and the emulsifier solution are emulsified, mechanically stirring at the rotating speed of 500rpm for 10min, adding 0.2mL of epoxy chloropropane, and stirring for 3h to generate a crosslinking reaction.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 50-150 mu m, the water absorption volume of 100mg of the calcium ion exchange porous starch hemostatic material in 30s is 1.2mL, and the content of calcium ions is as follows: 1-10 mg/g.

Comparative example 1

1) Pasting: same as in example 7.

2) Emulsification, pore-forming and crosslinking: the gelatinized starch solution obtained in step 1) and the emulsifier solution were emulsified at 50rpm as in example 2.

3) Calcium ion exchange: same as in example 7.

Through performance detection, the obtained calcium ion exchange porous starch hemostatic material has a particle size range of 10-1000 microns and a wide particle size span, which shows that the particle size distribution of the particles is not uniform, the material has poor degradation and absorption effects in vivo and has poor biocompatibility; the water absorption volume in 30s of the 100mg calcium ion exchange porous starch hemostatic material is 0.3mL, and the content of calcium ions is as follows: 1-10 mg/g.

Comparative example 2

1) Pasting: same as in example 7.

2) Emulsification, pore-forming and crosslinking: the gelatinized starch solution obtained in step 1) and the emulsifier solution were emulsified at 1200rpm as in example 7.

3) Calcium ion exchange: same as in example 7.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 30-45 microns, the particle size is too small, the particle flowability is poor, the water absorption volume in 30s of 100mg of the calcium ion exchange porous starch hemostatic material is 0.1mL, and the water absorption volume is also reduced due to poor flowability of the material; calcium ion content: 1-10 mg/g.

Comparative example 3

1) Pasting: same as in example 7.

2) Emulsification, pore-forming and crosslinking: the same as in example 7 except that the porogen was absolute ethanol and the volume added was 1000 ml.

3) Calcium ion exchange: same as in example 7.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 50-500 microns, the water absorption volume of 100mg of the calcium ion exchange porous starch hemostatic material in 30s is 0.6mL, and the content of calcium ions is as follows: 0.1-1 mg/g. After the addition amount of the pore-forming agent reaches the upper limit of the invention, the water absorption rate is not remarkably accelerated and the particle size distribution is not remarkably changed with the further increase of the use amount of the absolute ethyl alcohol, and the addition upper limit of the invention is selected in consideration of the production cost.

Comparative example 4

1) Pasting: same as in example 7.

2) Emulsification, pore-forming and crosslinking: the same as in example 7 except that the porogen was absolute ethanol and the volume added was 1 ml.

3) Calcium ion exchange: same as in example 7.

The particle surface topography of the obtained calcium ion exchange porous starch hemostatic material is shown in the C and D frames in FIG. 4, the C and D frames in FIG. 4 show that the adding amount of a pore-forming agent is too small, the surface roughness of the obtained particles is obviously reduced, the surface porous structure is also obviously reduced, the specific surface area is reduced, the water absorption volume of 30s is reduced, through performance detection, the particle diameter range is 50-500 micrometers, the water absorption volume of 100mg of the calcium ion exchange porous starch hemostatic material in 30s is 0.1mL, and the calcium ion content: 1-10 mg/g.

Comparative example 5

1) Pasting: same as in example 7.

2) Emulsification, pore-forming and crosslinking: the same as in example 7, except that the addition volume of the gelatinized starch solution was 500 ml.

3) Calcium ion exchange: same as in example 7.

Through performance detection, the calcium ion exchange porous starch hemostatic material has a particle size range of 1500-; the water absorption volume in 30s of the 100mg calcium ion exchange porous starch hemostatic material is 0.5mL, and the content of calcium ions is as follows: 1-10 mg/g.

Comparative example 6

1) Pasting: same as in example 7.

2) Emulsification, pore-forming and crosslinking: the same as in example 7, except that the addition volume of the gelatinized starch solution was 50 ml.

3) Calcium ion exchange: same as in example 7.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 30-70 microns, the particle size is too small, the particle flowability is poor, the water absorption volume in 30s of 100mg of the calcium ion exchange porous starch hemostatic material is 0.1mL, and the water absorption volume is also reduced due to poor flowability of the material; calcium ion content: 1-10 mg/g.

Comparative example 7

1) Pasting: same as in example 7.

2) Emulsification, pore-forming and crosslinking: same as in example 7.

3) Calcium ion exchange: after the cross-linking reaction is finished, respectively extracting for 3 times by using ethyl acetate and absolute ethyl alcohol, and drying for 8 hours in a 60 ℃ drying oven to obtain the granular hemostatic material, Co⁶⁰Sterilizing, sealing and storing for later use.

Through performance detection, the particle size range of the obtained calcium ion exchange porous starch hemostatic material is 50-150 microns, the water absorption volume of 100mg of the calcium ion exchange porous starch hemostatic material in 30s is 0.8mL, and the content of calcium ions is as follows: 0 mg/g.

Experiment 1: the content of metal ions in the calcium ion exchange porous starch hemostatic material is measured

Precisely weighing raw material starch (namely blank group), the calcium ion exchange porous starch hemostatic materials of examples 1-7 and 0.02g of the calcium ion exchange porous starch hemostatic materials of comparative examples 1-7, and respectively placing the raw material starch, the blank group, the calcium ion exchange porous starch hemostatic materials and the comparative examples in a centrifuge tube; respectively adding 1mL of concentrated nitric acid into the mixture, tightly covering the mixture, and putting the mixture into a water bath at 100 ℃ for digestion for 2 hours; and when the solution is transparent, opening the cover, diffusing the gas for 40min, centrifuging at the normal temperature of 4000rpm for 4min, taking the supernatant, diluting to a constant volume of 10mL by using ultrapure water, and uniformly mixing to obtain the sample to be detected.

ICP-MS is used for measuring the content of four metal ions of sodium, magnesium, potassium and calcium in a sample to be measured, the results of example 1 and example 7 are taken as examples, and the results are shown in figure 2. The instrument parameters are summarized as follows: radio frequency power: 1550W, atomizer: concentric atomization gas, MicroMist sampling depth: 8mm, carrier gas flow rate: 0.75L/min, make-up airflow rate: 0.40L/min, He gas flow rate: 3.3mL/min, plasma gas flow: 15L/min, repeated collection times: 3, an acquisition mode: Nogas/He mode. 5000. mu.g/mL of the polymer was used^-1Drawing the standard curve concentration of Na, Mg, K and Ca elements: 0. 0.01, 0.05, 0.1, 0.25, 1, 5, 20. mu.g/mL^-1。

The results in FIG. 2 show that, compared with the calcium ion-exchanged porous starch hemostatic material (i.e., comparative example 7) in which the calcium chloride saturated solution is added in an amount of 0mL, the calcium ion content in the calcium ion-exchanged porous starch hemostatic material of the present invention is increased from 0.26mg/g (blank group) to 2.5mg/g and 4.7mg/g, respectively, and the content of Na, Mg, and K metal ions is decreased at the same time, indicating that the calcium ions and the metal ions in the sample, such as Na, Mg, and K ions, are subjected to ion exchange reaction during the preparation process.

The results of other examples and comparative examples 1 to 6 are not significantly different from example 1, and are not repeated herein.

Experiment 2: determination of calcium ion exchange porous starch hemostatic material PBS (phosphate buffer solution) liquid absorption rate

The PBS liquid absorption rate can be used for evaluating the capacity of the starch hemostatic material to absorb and transfer water molecules under normal osmotic pressure of a human body, and the rapid PBS liquid absorption rate is also one of important evaluation indexes for measuring the hemostatic effect of the starch hemostatic material. The experimental set-up is shown in the left panel of fig. 3, with a 2mL pipette right fitted with a rubber tube, the other end of the rubber tube connected to an hourglass (G1), a 2mL pipette placed horizontally flat with the bottom end of the hourglass, and a 2mL pipette filled with PBS (pH 7.40). 100mg of Arista absorbable hemostatic particles, the calcium ion-exchanged porous starch hemostatic materials of examples 1-7 and comparative examples 1-7, respectively, were quickly placed inside an hourglass, and the timing was started and the change in volume of liquid in the pipette was recorded at 10s, 20s, 30s, 40s, 60s, 90s, and 120s, respectively, as exemplified by example 7, and the results are shown in the right panel of FIG. 3.

As shown in figure 3, the calcium ion exchange porous starch hemostatic material of the invention has the rapid liquid absorption capacity equivalent to that of the absorbable hemostatic particles in Arista within 20s, and the liquid absorption of the calcium ion exchange porous starch hemostatic material is gradually close to saturation after 20 s.

The results of other examples are slightly inferior to those of example 7, but no significant difference is observed, and the detailed description is omitted here. The results of comparative examples 1 to 7 were inferior to and significantly different from those of example 7 in liquid-absorbing effect.

Experiment 3: the particle size distribution of the calcium ion exchange porous starch hemostatic material particles is detected

0.2g of the calcium ion-exchanged porous starch hemostatic materials of examples 1 to 7 and comparative examples 1 to 7 and the raw starch were diluted and suspended in 200mL of anhydrous ethanol to obtain sample solutions, and the particle size distribution of particles in the sample solutions was measured by a Malvern 2000 laser particle sizer, and the results are shown in FIG. 4, taking example 7 as an example.

As can be seen from FIG. 4, the calcium ion exchange porous starch hemostatic material of the present invention has a uniform particle size distribution, wherein the average particle size is 78.13(d0.5) which is larger than the average particle size of the raw starch, and is suitable for hemostatic particle size; the particle size is too large, which is not beneficial to the degradation and absorption of the calcium ion exchange porous starch hemostatic material in vivo; too small, the calcium ion exchange porous starch hemostatic material has poor fluidity and low liquid absorption rate. Poor flowability is: if the particle size is small, the particles will have a large interaction force with each other due to some kind of interaction, which is not favorable for dispersion.

The results of other examples have no significant difference from example 7, and are not repeated herein. The hemostatic materials of comparative examples 1-7 had a non-uniform particle size distribution as compared to example 7.

Experiment 4: cytotoxicity test of calcium ion exchange porous starch hemostatic material

The calcium ion-exchanged porous starch hemostatic materials of examples 1 to 7 and comparative examples 1 to 7 were sterilized by irradiation with a cobalt source, and then immersed in RPMI 1640 culture medium (containing no serum, purchased from Saimer Feishel, USA) and extracted at 37 ℃ for 24 hours, and the supernatant was filtered to obtain a leaching solution. Inoculating L929 cells (mouse fibroblast, derived from national experimental cell resource sharing platform) into 96-well plate (complete culture medium containing RPMI 1640 culture solution and fetal calf serum is preset in the plate), wherein each well is 5 × 10⁴Then, the 96-well plate was placed in an incubator and incubated at 37 ℃ for 24 hours. Taking out 96-well plate, discarding old solution, adding 100 μ L of 100% leaching solution and 50% leaching solution (50% leaching solution is obtained by mixing 100% leaching solution and equal volume of RPMI 1640 culture solution) collected into each well, and culturing at 37 deg.C in incubator. And taking out after 48h, adding 20 mu L of MTT (thiazole blue purchased from Kyoto Beijing) aqueous solution of 5mg/ml into each hole, and continuously placing in an incubator to react for 4h at 37 ℃. And finally, taking out the 96-well plate, carefully discarding the old solution, adding 150 mu L of DMSO (dimethyl sulfoxide) into each well, shaking for 10min, and placing the well in an enzyme-linked immunosorbent assay (ELISA) instrument to read the OD value. The test wavelength is 570nm and the reference wavelength is 630 nm. Each sample was prepared with 6 duplicate wells, and a blank culture medium (same procedure as the experimental group except that no hemostatic material was added) and 0.5 wt% phenol aqueous solution were used as a negative control group and a positive control group, respectively. The Relative proliferation rate (RGR%) was calculated as follows: RGR% ═ OD_{Sample (I)}/OD_{Negative control}X 100%, the experimental results are shown in FIG. 7, taking example 7 as an example.

The results show that: as can be seen from fig. 7, referring to the negative control group, the relative cell proliferation rate of the calcium ion-exchanged porous starch hemostatic material group of the present invention is greater than 100%, which indicates that the calcium ion-exchanged porous starch hemostatic material of the present invention has no cytotoxicity, and the hemostatic material has a certain cell proliferation promoting effect, and can promote wound healing to a certain extent.

The relative cell proliferation rates of other examples and comparative examples 1-6 are not significantly different from those of example 7, and are not repeated herein.

Experiment 5: whole blood coagulation dynamics determination of calcium ion exchange porous starch hemostatic material

Taking 180-220g of healthy adult Wistar rats, and carrying out anesthesia by intraperitoneal injection of 3wt% pentobarbital sodium aqueous solution at the dose of 5mg/kg after weighing; after anesthetizing the rat, taking blood from the heart in a supine position, and mixing the whole blood and the anticoagulant in a volume ratio of 1:9 of 3.8 wt% sodium citrate aqueous solution for anticoagulation to obtain anticoagulated whole blood. Respectively weighing 10mg of calcium ion exchange porous starch hemostatic materials of Arista, examples 1-7 and comparative examples 1-7, placing the materials in a 5mL centrifuge tube, quickly taking 100 mu L of anticoagulated whole blood by using a micro pipette, adding the anticoagulated whole blood into the centrifuge tube, starting timing, adding 3mL of deionized water after 5min, 20min, 35 min and 50min, and cracking erythrocytes which are not wrapped by blood clots; after standing for 5min, 200. mu.L of the supernatant was collected and absorbance at 540nm was measured, as in example 7, and the results are shown in FIG. 6.

The results show that: compared with Arista absorbable hemostatic particles, the calcium ion exchange porous starch hemostatic material has a remarkable procoagulant effect in vitro. Compared with comparative example 7, the calcium ion exchange porous starch hemostatic material of the invention has excellent procoagulant effect in vitro.

Other examples have in vitro procoagulant effects equivalent to those of example 1, and no significant differences are found, and are not repeated here. Comparative examples 1-6 exhibited less in vitro procoagulant effects than example 1 and were significantly different, comparable to Arista absorbable hemostatic particles.

Experiment 6: evaluation of hemostatic effect of calcium ion exchange porous starch hemostatic material-mouse tail-breaking model

100mg of gauze, Arista absorbable hemostatic particles, calcium ion-exchanged porous starch hemostatic materials of examples 1-7 and comparative examples 1-7 were weighed and placed in 2mL centrifuge tubes, respectively, as samples. Male, Kunming mice about 33-39g, each group of 10 mice, according to 50mg/kg dose intraperitoneal injection 3wt% pentobarbital sodium water solution anesthesia. The limbs of the mice were fixed on a mouse plate, the tail length was measured, the tail drooped freely, from the tip of the tail, the tail was cut off 1/2 length with surgical scissors, free bleeding was done for 30s (recording the amount of bleeding for 30 s), and then the sample was inserted and pressed gently. After pressing for 2 minutes, the sample is taken out, and if bleeding continues, another sample is inserted, the bleeding is stopped for 2 minutes, and the sample is taken out and observed. The rat tail naturally droops, and within ten minutes, no active bleeding is marked as successful hemostasis; if the bleeding is still not stopped after the hemostasis is pressed twice, the failure of the hemostasis is recorded, and the hemostasis process of each mouse is pressed twice at most; if the hemostasis is successful after the hemostasis is pressed for the first time, the hemostasis is not pressed for the second time. The amount of bleeding and the number of times of hemostasis were recorded, and the results are shown in Table 1 and FIG. 8, taking example 7 as an example.

TABLE 1 calcium ion-exchange porous starch hemostatic Material hemostatic Effect

The results show that: from the results of table 1 and fig. 8, it can be seen that the calcium ion exchange porous starch hemostatic material of the present invention has a hemostatic success rate of 100%, and both the number of times of hemostasis and the amount of bleeding during the hemostasis process are less than Arista absorbable hemostatic particles and gauze, which indicates that the calcium ion exchange porous starch hemostatic material has a hemostatic success rate significantly better than Arista absorbable hemostatic particles in the mouse tail-broken bleeding model.

In terms of bleeding amount, the bleeding amount of a mouse using the calcium ion-exchange porous starch hemostatic material of the present invention is 0.05g, the bleeding amount of a mouse using Arista to absorb the hemostatic particles is 0.11g, the bleeding amount of a mouse using gauze is 0.295g, and the bleeding amount of a mouse using the hemostatic material of the present invention is less than half of the bleeding amount of Arista to absorb the hemostatic particles, which is significantly lower than that of the bleeding amount of the mouse using Arista to absorb the hemostatic particles and gauze.

The bleeding amount of other examples is slightly higher than that of example 7, but there is no significant difference, and the description is omitted here. The results of comparative examples 1-7 are less effective and significantly different than the imbibing effect of example 7, comparable to Arista absorbable hemostatic particles.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the content of the present invention.

Claims

1. A method for preparing calcium ion-exchange porous starch hemostatic material comprises gelatinizing starch; emulsifying, pore-forming and crosslinking the gelatinized starch solution; the method is characterized by also comprising calcium ion exchange after the crosslinking is finished, wherein the calcium ion exchange is to add a saturated calcium chloride solution into a reaction solution after the crosslinking, and filter the obtained solid to obtain the calcium ion exchange porous starch hemostatic material;

the calcium ion exchange porous starch hemostatic material comprises the following raw materials in percentage by mass:

0.2 to 6.5 weight percent of starch;

15-87 wt% of oil phase;

0.2wt% -45wt% of pore-foaming agent;

0.01-7.6 wt% of emulsifier;

0.01-2 wt% of calcium chloride;

0.01wt% -3wt% of cross-linking agent;

the balance of water;

the gelatinization of the starch specifically comprises the following steps: adding water into starch to prepare a starch water solution with the starch concentration of 2-10 wt%, heating at 50-300rpm and 45-65 ℃ for 1-10min, cooling to 20-30 ℃, and adjusting the pH to 9.0-11.0 after cooling to obtain a gelatinized starch solution;

emulsifying, pore-forming and crosslinking the gelatinized starch solution, namely mixing an emulsifier and an oil phase to prepare an emulsifier solution, adding the gelatinized starch solution into the emulsifier solution, stirring for emulsifying, adding a pore-forming agent after emulsifying, stirring for pore-forming, and then adding a crosslinking agent for crosslinking;

the cross-linking agent is epichlorohydrin.

2. The method of claim 1, wherein the emulsifier comprises from about 0.1 to about 1.5% by volume of the oil phase.

3. The method of claim 2, wherein the emulsifier comprises from about 0.5 to about 1.0% by volume of the oil phase.

4. The method of claim 1, wherein the porogen is selected from one or more of polyethylene glycol, ethanol, and methanol.

5. The method according to claim 1, wherein the starch is selected from one or more of potato starch, sweet potato starch, tapioca starch, corn starch, mung bean starch, water chestnut starch, lotus root starch and wheat starch; and/or

The oil phase is selected from one or more of cyclohexane-chloroform mixture, liquid paraffin and soybean oil; and/or

The emulsifier is selected from one or more of span80, span60 and tween 20.

6. The method according to any one of claims 1 to 5, wherein the stirring speed during the emulsification is 200-1000 rpm.

7. The method according to any one of claims 1 to 5, wherein the volume ratio of the emulsifier solution to the gelatinized starch solution is (0.5-8): 1; and/or

8. The method of claim 6, wherein the volume ratio of the emulsifier solution to the gelatinized starch solution is (0.5-8): 1; and/or

9. The method according to claim 7, wherein the volume ratio of the emulsifier solution to the gelatinized starch solution is (1-4): 1.

10. the method according to claim 8, wherein the volume ratio of the emulsifier solution to the gelatinized starch solution is (1-4): 1.

11. the method according to any one of claims 1 to 5, wherein the emulsifying, pore-forming and cross-linking of the gelatinized starch solution are specifically: adding the emulsifier into the oil phase, and stirring until the emulsifier is uniformly mixed with the oil phase to obtain an emulsifier solution; heating the emulsifier solvent to 40-60 ℃, adding the gelatinized starch solution into the emulsifier solution, emulsifying at 200-1000rpm, adding the pore-forming agent, stirring at 200-1000rpm for 5-20min, and adding the cross-linking agent for cross-linking reaction for 2-8 h.

12. The method as claimed in claim 6, wherein the emulsification, pore-forming and cross-linking of the gelatinized starch solution are specifically: adding the emulsifier into the oil phase, and stirring until the emulsifier is uniformly mixed with the oil phase to obtain an emulsifier solution; heating the emulsifier solvent to 40-60 ℃, adding the gelatinized starch solution into the emulsifier solution, emulsifying at 200-1000rpm, adding the pore-forming agent, stirring at 200-1000rpm for 5-20min, and adding the cross-linking agent for cross-linking reaction for 2-8 h.

13. The method as claimed in claim 7, wherein the emulsification, pore-forming and cross-linking of the gelatinized starch solution are specifically: adding the emulsifier into the oil phase, and stirring until the emulsifier is uniformly mixed with the oil phase to obtain an emulsifier solution; heating the emulsifier solvent to 40-60 ℃, adding the gelatinized starch solution into the emulsifier solution, emulsifying at 200-1000rpm, adding the pore-forming agent, stirring at 200-1000rpm for 5-20min, and adding the cross-linking agent for cross-linking reaction for 2-8 h.

14. The method as claimed in claim 8, wherein the emulsification, pore-forming and cross-linking of the gelatinized starch solution are specifically: adding the emulsifier into the oil phase, and stirring until the emulsifier is uniformly mixed with the oil phase to obtain an emulsifier solution; heating the emulsifier solvent to 40-60 ℃, adding the gelatinized starch solution into the emulsifier solution, emulsifying at 200-1000rpm, adding the pore-forming agent, stirring at 200-1000rpm for 5-20min, and adding the cross-linking agent for cross-linking reaction for 2-8 h.

15. The method as claimed in claim 9, wherein the emulsifying, pore-forming and cross-linking of the gelatinized starch solution are specifically: adding the emulsifier into the oil phase, and stirring until the emulsifier is uniformly mixed with the oil phase to obtain an emulsifier solution; heating the emulsifier solvent to 40-60 ℃, adding the gelatinized starch solution into the emulsifier solution, emulsifying at 200-1000rpm, adding the pore-forming agent, stirring at 200-1000rpm for 5-20min, and adding the cross-linking agent for cross-linking reaction for 2-8 h.

16. The method as claimed in claim 10, wherein the emulsifying, pore-forming and cross-linking of the gelatinized starch solution are specifically: adding the emulsifier into the oil phase, and stirring until the emulsifier is uniformly mixed with the oil phase to obtain an emulsifier solution; heating the emulsifier solvent to 40-60 ℃, adding the gelatinized starch solution into the emulsifier solution, emulsifying at 200-1000rpm, adding the pore-forming agent, stirring at 200-1000rpm for 5-20min, and adding the cross-linking agent for cross-linking reaction for 2-8 h.

17. Use of a calcium ion-exchanged porous starch haemostatic material prepared by a method according to any of claims 1-16 in the manufacture of a haemostat for bleeding from a complex wound and/or bleeding from a patient suffering from a clotting dysfunction.

18. The use of claim 17, wherein the complicated wound bleeding is bleeding from parenchymal organs in vivo, or bleeding from disseminated capillaries, or bleeding from inflamed and fragile tissues.

19. The use according to claim 17 or 18, wherein the calcium ion-exchanged porous starch hemostatic material has a particle size of 50 to 1500 μm, a water absorption volume of 0.2 to 1.2mL per 100mg of the hemostatic material in 30s, and a calcium ion content of 0.1 to 15 mg/g.

20. The use of claim 19, wherein the volume of water absorbed per 100mg of the hemostatic material in 30s is 0.5-1.2 mL.