Absorbable cellulose hemostatic material and preparation method thereof

Abstract

The invention relates to the technical field of medical instruments, in particular to an absorbable cellulose hemostatic material and a preparation method thereof. The cellulose is regenerated cellulose, the cross section of the cellulose is a special-shaped section, including but not limited to hollow, trilobal, Y-shaped, cross-shaped or flat, and compared with common fibers with the same linear density, the cellulose has the advantages of larger specific surface area, better chemical modification uniformity, higher imbibition and hemostasis capacity and higher in-vivo degradation and absorption rate. The invention provides an absorbable cellulose hemostatic material prepared from special-shaped fibers, the cross section of the fibers can be hollow, trilobal, Y-shaped, cross-shaped and the like, and the absorbable hemostatic material can be woven, non-woven fabric, powder and particles. Compared with an existing absorbable cellulose hemostatic material, the absorbable hemostatic material prepared from the special-shaped fibers is large in specific surface area, better in chemical modification uniformity, better in water absorption or blood absorption performance and hemostatic performance and higher in in-vivo degradation and absorption rate.

Description

Technical Field

[0001] The invention relates to the technical field of medical devices, in particular to an absorbable cellulose hemostatic material and a preparation method thereof. Background Art

[0002] Surgical operations are often inevitably accompanied by a certain degree of damage to the surface of organ tissues, which in turn leads to bleeding, oozing and exudation, infection and other phenomena. If bleeding continues, it will affect wound healing and increase the possibility of infection, which is not conducive to postoperative recovery. If the amount of bleeding is large, it may cause hemorrhagic shock and endanger the patient's life. At the same time, bleeding will also cause the surgical field to be blurred, which is not conducive to the implementation of the operation. Therefore, the success or failure of hemostasis is often one of the key factors that determine the success or failure of the operation. If there is a lot of bleeding or hemostasis is not thorough during the operation, it may cause serious consequences.

[0003] Absorbable hemostatic materials refer to medical materials that are applied to the bleeding site of the wound, achieve the purpose of hemostasis by accelerating the blood coagulation process, and can be degraded and absorbed by the human body within a certain period of time. Absorbable hemostatic materials can not only achieve rapid and effective hemostasis, but also avoid secondary damage caused by removal after hemostasis due to their degradable or absorbable properties. Therefore, absorbable hemostatic materials have shown certain advantages in reducing patient bleeding, shortening operation time, and improving prognosis during surgical operations. At present, a variety of hemostatic materials with different compositions and mechanisms have been developed, such as gelatin, collagen, cellulose, and fibrin glue. These materials are applied to different parts due to their respective characteristics.

[0004] Absorbable cellulose hemostatic materials are hemostatic materials made of chemically modified cellulose, such as absorbable oxidized regenerated cellulose fiber gauze and etherified sodium carboxymethyl cellulose soluble fiber gauze, as well as powder or granules obtained by crushing absorbable hemostatic fibers. Different types of cellulose hemostatic materials have different hemostatic mechanisms. Absorbable oxidized regenerated cellulose contains carboxyl groups. After contacting with blood, it absorbs blood. The acidic carboxyl groups can cause red blood cells to rupture and release hemoglobin, and form brown gel with ferrous ions in hemoglobin, which seals and blocks the ends of capillaries. At the same time, it stimulates the activation of aggregated platelets to form thrombi, accelerates endogenous coagulation, and achieves the purpose of hemostasis. Its function does not rely on the body's coagulation mechanism, and can quickly promote blood coagulation and effectively achieve the purpose of controlling bleeding. Etherified sodium carboxymethyl cellulose soluble fiber gauze has a strong affinity for water and saline. When it encounters blood, it can quickly absorb the water in the blood and dissolve. The colloid formed blocks the ends of capillaries, promotes blood concentration, increases viscosity, and slows down blood flow, thereby achieving the purpose of hemostasis.

[0005] The degree of chemical modification of cellulose, such as oxidation degree or etherification grafting rate, is a key factor affecting the hemostatic performance and in vivo absorption performance of cellulose hemostatic materials. For thicker fibers, the degree of modification inside and on the surface of the fibers is different to a certain extent, so a longer chemical modification time is required, and it is not conducive to the absorption of the fibers in the human body. In order to improve the uniformity and absorbability of the chemical modification of cellulose, people usually use a lower fiber line density, that is, use finer fiber filaments. For example, patent US3364200 mentions that it is best to use 1-3dtex fiber filaments or yarns and braids formed by twisting these fiber filaments for oxidation. Patent CN107823693B mentions the use of nanofiber filaments to make hemostatic fiber membranes. The diameter of this fiber filament is 1-1000nm, with a high specific surface area. The nanofibers overlap each other to form a hemostatic membrane, which improves the adhesion to the tissue and the hemostatic effect. Patent CN106421875B mentions that 1.2-3 dtex fibers are oxidized to obtain oxidized cellulose, and the oxidation system used is TEMPO-sodium bromide-organic solvent-water. During the oxidation process, the fiber surface swells or gels, and the original shape of the fiber cannot be maintained. The absorbable hemostatic gauze made of finer fibers is also conducive to improving the degradation and absorption of fibers in the human body.

[0006] The use of finer fibers to prepare absorbable cellulose hemostatic materials can improve the uniformity of chemical modification and in vivo absorbability, increase the contact area between the hemostatic material and blood and the blood absorption rate, and thus improve the hemostatic effect. However, there are also certain disadvantages, such as: limited water or blood absorption performance, easy breakage of fibers during processing, low strength, etc., especially after irradiation sterilization, and long-term storage and aging, the finer fibers are more likely to break, resulting in problems such as doctors being unable to operate the gauze and falling off.

[0007] Therefore, in view of this, the existing technology is studied and improved, and an absorbable cellulose hemostatic material and a preparation method thereof are proposed. Summary of the invention

[0008] The present invention provides an absorbable cellulose hemostatic material prepared from special-shaped fibers, wherein the cross-section of the fibers may be hollow, trilobal, Y-shaped, cross-shaped, etc., and the absorbable hemostatic material may be in the form of weaving, non-woven fabric, powder, and granules, etc. Compared with existing absorbable cellulose hemostatic materials, the absorbable hemostatic material prepared from special-shaped fibers has a large specific surface area, better uniformity of chemical modification, better water or blood absorption and hemostatic performance, and faster degradation and absorption rate in vivo.

[0009] The technical solution adopted by the present invention is: an absorbable cellulose hemostatic material, the cellulose is regenerated cellulose, and its cross-section is a special-shaped cross-section, including but not limited to hollow, trilobal, Y-shaped, cross-shaped or flat. Compared with ordinary fibers of the same linear density, it has a larger specific surface area, better chemical modification uniformity, higher liquid absorption and hemostatic ability, and faster in vivo degradation and absorption rate.

[0010] As a further solution of the present invention: the regenerated cellulose is one of viscose fiber, lyocell fiber, modal fiber or cuprammonium fiber, preferably viscose fiber.

[0011] As a further embodiment of the present invention: the hemostatic material is in the form of any one of woven fabric, non-woven fabric, powder or granules.

[0012] As a further solution of the present invention: the fiber linear density is 1-6 dtex, and the degree of polymerization of the absorbable regenerated cellulose hemostatic material is 20-200.

[0013] A method for producing an absorbable cellulose hemostatic material comprises the following specific steps:

[0014] A) putting the shaped fiber or its braided fabric as raw material into a reaction kettle filled with an inert organic solvent and cooling it to 0-10°C;

[0015] B) slowly adding nitrogen oxide into the reaction kettle, raising the temperature to 15-30° C. and reacting for 20-40 hours;

[0016] C) After the reaction, the heteromorphic fibers or heteromorphic fiber braids are taken out, washed, centrifuged and dried to obtain an absorbable hemostatic material.

[0017] As a further solution of the present invention: in the step A), during the fiber spinning process, the special-shaped fibers are obtained by designing the spinneret holes to obtain corresponding hollow, trilobal, Y-shaped, cross-shaped, flat and other special-shaped fiber raw materials, and the polymerization degree of the special-shaped fiber raw materials is 100-500; in the step A), the inert organic solvent includes one or more of cyclohexane, n-hexane, carbon tetrachloride, chloroform, dichloromethane, fluorocarbon or hydrofluoroether.

[0018] As a further solution of the present invention: in the step B), the mass ratio of the nitrogen oxide to the inert solvent is 1:(10-50), and the mass ratio of the nitrogen oxide to the special-shaped fiber or its woven fabric is 1:(0.7-1.5).

[0019] As a further solution of the present invention: in the step C), the cleaning medium is one or more of water, ethanol, methanol or isopropanol, and the drying method is forced air drying or vacuum drying.

[0020] As a further solution of the present invention: the nonwoven fabric is obtained by opening, carding, laying and cutting the oxidized special-shaped fibers.

[0021] As a further solution of the present invention: the powder or granules are obtained by crushing, granulating and screening the oxidized special-shaped fibers or their woven fabrics.

[0022] Beneficial effects of the present invention:

[0023] 1. Improve hemostasis effect

[0024] 1. Increase contact area: By using special-shaped fibers (such as trilobal, hollow, Y-shaped, cross-shaped, etc.), the contact area between the fiber and body fluids or blood is increased, thereby improving blood absorption and hemostasis performance. This design allows the fiber to absorb blood more effectively and quickly form gel or thrombus to seal the wound, achieving the purpose of rapid hemostasis.

[0025] 2. Optimized chemical modification: The uniform chemical modification of the special-shaped fibers makes the hemostatic material have better water or blood absorption and hemostatic properties. Compared with traditional round fibers, special-shaped fibers can better maintain structural integrity during the modification process, thereby improving the modification effect and hemostatic efficiency.

[0026] 2. Improve degradation and absorption in the body

[0027] 1. Accelerate the degradation rate: The preparation method and chemical modification of the special-shaped fibers not only improve the hemostatic effect, but also accelerate the degradation rate of the hemostatic material in the body. This allows the hemostatic material to be quickly absorbed by the human body after completing the hemostatic task, avoiding the need for secondary surgery to remove it, and reducing the patient's pain and recovery time.

[0028] 2. Optimize fiber linear density: By selecting the appropriate fiber linear density (such as 1-6dtex), the strength and operability of the fiber are guaranteed, and the degradation and absorption of the fiber in the body are facilitated. This design allows the hemostatic material to better adapt to the physiological environment of the human body while meeting the hemostatic needs.

[0029] 3. Improve material strength and processing performance

[0030] 1. Enhance fiber strength: In the preparation process of special-shaped fibers, by optimizing the spinneret hole design and spinning process, fibers with higher strength can be obtained. This solves the problem that traditional thinner fibers are easy to break during processing and improves the durability and operability of hemostatic materials.

[0031] 2. Improved processing performance: Hemostatic materials made of special-shaped fibers can be easily processed into various forms such as woven fabrics, non-woven fabrics, powders and granules. This diversity meets the requirements of different surgical sites and hemostasis needs, and improves the applicability and flexibility of hemostatic materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a micrograph of ordinary viscose fiber.

[0033] Figure 2 A microscopic view of a trilobal fiber of an absorbable cellulose hemostatic material and a preparation method thereof according to the present invention Figure 1 .

[0034] Figure 3 A microscopic view of a trilobal fiber of an absorbable cellulose hemostatic material and a preparation method thereof according to the present invention Figure 2 . DETAILED DESCRIPTION

[0035] The present invention will be further described below.

[0036] Example 1

[0037] 1) Add 7500 ml of n-hexane solvent into a reaction vessel, lower the temperature to about 10 degrees, and add about 300 ml of nitrogen oxide;

[0038] 2) immersing 300 g of trilobal viscose fiber in the above-mentioned solvent containing nitrogen oxides, wherein the degree of polymerization of the fiber is 100-400 and the linear density is 3.3 dtex;

[0039] 3) Slowly increase the reaction temperature, maintain the system temperature at 15-25 degrees, and the total reaction time is 24-40 hours;

[0040] 4) Take out the fiber from the reaction vessel, wash it with an ethanol aqueous solution until the pH is constant, 5000 ml each time, and finally replace the water with ethanol;

[0041] 5) The fibers are taken out, centrifuged and vacuum dried to obtain absorbable oxidized regenerated cellulose fibers. The carboxyl content of the fibers obtained in this example is measured to be 20.5%.

[0042] 6) Processing of nonwoven fabrics: using nonwoven equipment to open, card, lay nets, cut and other processes on the above fibers to make absorbent hemostatic fiber products, the gram weight of the fiber products is 120-150 grams.

[0043] Example 2

[0044] 1) Add 7500 ml of fluoroether solvent into a reaction vessel, lower the temperature to about 10 degrees, and add about 300 ml of nitrogen oxide;

[0045] 2) immersing 300 g of a woven fabric of trilobal viscose fiber into the above-mentioned solvent containing nitrogen oxides, wherein the degree of polymerization of the fiber is 100-400, the linear density of the fiber is 3.3 dtex, and the linear density of the yarn is 60 dtex;

[0046] 3) Slowly increase the reaction temperature, maintain the system temperature at 15-25 degrees, and the total reaction time is 24-40 hours;

[0047] 4) taking out the woven fabric from the reaction vessel, washing it with an ethanol aqueous solution until the pH is constant, 5000 ml each time, and finally replacing the water therein with ethanol;

[0048] 5) The fibers are taken out, centrifuged and vacuum dried to obtain absorbable hemostatic gauze. The carboxyl content of the fibers obtained in this example is measured to be 19.7%.

[0049] Comparative Example 1

[0050] 1) Add 7500 ml of n-hexane solvent into a reaction vessel, lower the temperature to about 10 degrees, and add about 300 ml of nitrogen oxide;

[0051] 2) immersing 300 g of ordinary viscose fiber in the above-mentioned solvent containing nitrogen oxides, wherein the degree of polymerization of the fiber is 100-400 and the linear density is 3.1 dtex;

[0052] 3) Slowly increase the reaction temperature, maintain the system temperature at 15-25 degrees, and the total reaction time is 24-40 hours;

[0053] 4) Take out the fiber from the reaction vessel, wash it with an ethanol aqueous solution until the pH is constant, 5000 ml each time, and finally replace the water with ethanol;

[0054] 5) The fibers are taken out, centrifuged and vacuum dried to obtain absorbable oxidized regenerated cellulose fibers. The carboxyl content of the fibers obtained in this example is measured to be 19.3%.

[0055] 6) Processing of nonwoven fabrics: using nonwoven equipment to open, card, lay nets, cut and other processes on the above fibers to make absorbent hemostatic fiber products, the gram weight of the fiber products is 120-150 grams.

[0056] Comparative Example 2

[0057] 1) Add 7500 ml of fluoroether solvent into a reaction vessel, lower the temperature to about 10 degrees, and add about 300 ml of nitrogen oxide;

[0058] 2) immersing 300 g of ordinary viscose fiber in the above-mentioned solvent containing nitrogen oxides, wherein the degree of polymerization of the fiber is 100-400 and the linear density is 1.6 dtex;

[0059] 3) Slowly increase the reaction temperature, maintain the system temperature at 15-25 degrees, and the total reaction time is 24-40 hours;

[0060] 4) Take out the fiber from the reaction vessel, wash it with an ethanol aqueous solution until the pH is constant, 5000 ml each time, and finally replace the water with ethanol;

[0061] 5) The fibers are taken out, centrifuged and vacuum dried to obtain absorbable oxidized regenerated cellulose fibers. The carboxyl content of the fibers obtained in this example is measured to be 20.8%.

[0062] 6) Processing of nonwoven fabrics: using nonwoven equipment to open, card, lay nets, cut and other processes on the above fibers to make absorbent hemostatic fiber products, the gram weight of the fiber products is 120-150 grams.

[0063] The water absorption of hemostatic materials was tested according to "YY / T 0471.1-2004 Test Methods for Contact Wound Dressings Part 1: Liquid Absorption", and the results are as follows:

[0064]

[0065]

[0066] The comparison between the special-shaped fibers of the present invention and ordinary fibers is as follows: Figure 1-3 As shown, the surface of the trilobal fiber not only has the grooved surface cortical structure of the ordinary fiber surface, but also has a special cross-section. Compared with ordinary fibers, this special fiber has a larger contact area with body fluids or blood, and has better fluid absorption and hemostasis properties; even with a larger linear density, it has a faster in vivo degradation rate.

[0067] Other hollow, Y-shaped, cross-shaped, flat and other special-shaped fibers can be easily produced through the design of the spinneret, and during the oxidation treatment process, the cross-sectional structure of the special-shaped fibers can be retained, thereby obtaining the final absorbable hemostatic material with a special-shaped fiber cross-section.

[0068] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An absorbable cellulose hemostatic material, characterized in that: The cellulose is regenerated cellulose, and its cross section is a special-shaped cross section, including but not limited to hollow, trilobal, Y-shaped, cross-shaped or flat. Compared with ordinary fibers of the same linear density, it has a larger specific surface area, better chemical modification uniformity, higher liquid absorption and hemostasis capabilities, and a faster degradation and absorption rate in the body.

2. The absorbable cellulose hemostatic material according to claim 1, characterized in that: The regenerated cellulose is one of viscose fiber, lyocell fiber, modal fiber or cuprammonium fiber, preferably viscose fiber.

3. The absorbable cellulose hemostatic material according to claim 2, characterized in that: The hemostatic material may be in the form of woven fabric, non-woven fabric, powder or granules.

4. The absorbable cellulose hemostatic material according to claim 3, characterized in that: The fiber linear density is 1-6 dtex, and the polymerization degree of the absorbable regenerated cellulose hemostatic material is 20-200.

5. A method for preparing the absorbable cellulose hemostatic material according to claim 4, comprising the following specific steps: A) putting the shaped fiber or its braided fabric as raw material into a reaction kettle filled with an inert organic solvent and cooling it to 0-10°C; B) slowly adding nitrogen oxide into the reaction kettle, raising the temperature to 15-30° C. and reacting for 20-40 hours; C) After the reaction, the heteromorphic fibers or heteromorphic fiber braids are taken out, washed, centrifuged and dried to obtain an absorbable hemostatic material.

6. The method of absorbable cellulose hemostatic material according to claim 5, characterized in that: In the step A), during the spinning process of the shaped fibers, the corresponding hollow, trilobal, Y-shaped, cross-shaped, flat and other shaped raw materials of the shaped fibers are obtained by designing the spinneret holes, and the polymerization degree of the shaped fiber raw materials is 100-500; in the step A), the inert organic solvent includes one or more of cyclohexane, n-hexane, carbon tetrachloride, chloroform, dichloromethane, fluorocarbon or hydrofluoroether.

7. The method of absorbable cellulose hemostatic material according to claim 5, characterized in that: In the step B), the mass ratio of the nitrogen oxide to the inert solvent is 1:(10-50), and the mass ratio of the nitrogen oxide to the special-shaped fiber or its woven fabric is 1:(0.7-1.5).

8. The method of absorbable cellulose hemostatic material according to claim 5, characterized in that: In the step C), the cleaning medium is one or more of water, ethanol, methanol or isopropanol, and the drying method is forced air drying or vacuum drying.

9. The method of absorbable cellulose hemostatic material according to claim 5, characterized in that: The nonwoven fabric is obtained by opening, combing, laying and cutting oxidized special-shaped fibers.

10. The absorbable cellulose hemostatic material according to claim 5, characterized in that: The powder or granules are obtained by crushing, granulating and screening the oxidized special-shaped fibers or their woven fabrics.

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