Preparation method of novel hemostatic sponge

Abstract

The preparation method of the novel hemostatic sponge comprises the following steps: step 1, constructing a pH response network system; step 1.1, constructing a dual-network gel composite system; step 1.2, constructing a response mechanism; step 2, loading and releasing bletilla striata polysaccharide; step 2.1, a loading mode of bletilla striata polysaccharide; 2.2, the release mode of the bletilla striata polysaccharide is determined; step 3, conducting function optimization; step 3.1, constructing a conductive path; and step 3.2, electric stimulation collaboration. The invention aims to realize a more efficient and safer hemostatic effect by constructing a pH response network system, loading bletilla striata polysaccharide and optimizing a conductive function. The method is simple in preparation process and low in cost, and the prepared hemostatic sponge has good biocompatibility, degradability and hemostatic performance and is expected to become an important development direction in the field of hemostatic materials in the future.

Description

Technical Field

[0001] The invention relates to the technical field of medical treatment, in particular to a preparation method of a novel hemostatic sponge. Background Art

[0002] The existing technology of hemostatic sponge mainly includes the following: Electrospinning nanosponge technology: Using electrospinning, natural biomaterials such as acellular dermal matrix, silk fibroin, gelatin, collagen, or chitosan are transformed into nanofibers. These fibers are then cross-linked to form a loose sponge with a nanoporous three-dimensional structure or a nanohemostatic sponge with an aerogel structure. These nanohemostatic sponges exhibit high porosity, surface area, blood absorption, low bulk density, and ultralight weight, significantly enhancing hemostatic performance and helping to establish a microenvironment in defective tissue that mimics the structure and function of the natural extracellular matrix.

[0003] Nanomaterial composite technology: Composite nanomaterials with traditional hemostatic sponge materials. For example, adding antibacterial nanomaterials such as nanosilver to chitosan sponge can further improve the antibacterial properties of the hemostatic sponge; adding nano-scale bioactive factors, such as growth factors, can promote wound healing.

[0004] Application of aerogel technology in hemostatic sponges: Hemostatic sponges are prepared using aerogel technology. Biomaterials are formed into nanofiber membranes, dissolved in a solvent, homogenized, molded, freeze-dried, and cross-linked to create an aerogel-structured hemostatic sponge. Aerogel nanohemostatic sponges can be custom-made using different molds to create different three-dimensional structures with strong mechanical properties and high compression resistance. When applied to wound surfaces, they absorb large amounts of blood, activate the coagulation system, and promote clot formation, achieving rapid hemostasis. They also mimic the function and structure of the extracellular matrix, promoting wound healing.

[0005] Expandable hemostatic sponge technology: This highly swellable hemostatic sponge is prepared by controlling the vacuum level to create a porous structure. A photoinduced double-bond compound is cross-linked to form a chemical network to maintain the sponge's shape. Soaking the sponge in a saline solution induces the formation of a physical cross-linked chitosan network, giving the sponge excellent shape recovery. This hemostatic sponge rapidly expands after absorbing blood, sealing the bleeding wound and preventing itself from being swept away by the bloodstream, effectively sealing the wound. It can be manufactured in various shapes and sizes to suit different wounds.

[0006] At present, although the above-mentioned hemostatic sponge technologies have their own advantages in terms of hemostatic effect, antibacterial properties, and promotion of wound healing, they still have some limitations. For example, although electrospinning nanosponge technology has high porosity and high blood absorption rate, its preparation process is relatively complex and the cost is high; although nanomaterial composite technology can enhance the antibacterial properties of hemostatic sponges, the safety and biocompatibility of nanomaterials still need further evaluation; although aerogel hemostatic sponges have excellent mechanical properties and hemostatic effects, their preparation process is complex, and the brittleness of the material itself may affect their use in certain application scenarios; although expandable hemostatic sponges can quickly expand and seal wounds, their shape recovery ability and mechanical strength need to be improved. Summary of the Invention

[0007] To address the aforementioned challenges in the existing technologies, the present invention proposes a novel method for preparing a hemostatic sponge. This method aims to achieve more efficient and safer hemostasis by constructing a pH-responsive network system, loading it with Bletilla striata polysaccharide, and optimizing its electrical conductivity. This method not only offers a simple and cost-effective preparation process, but also produces a hemostatic sponge with excellent biocompatibility, degradability, and hemostatic properties, promising future development in the field of hemostatic materials.

[0008] The technical solution adopted by the present invention to solve its technical problem is: A method for preparing a novel hemostatic sponge comprises the following steps: Step 1: Construction of pH-responsive network system; Step 1.1, constructing a double network gel composite system: Materials: chitosan, sodium alginate and acetic acid solution; wherein, the deacetylation degree of chitosan is ≥90%, the mass ratio of chitosan to sodium alginate is 1:1, and the pH of the acetic acid solution is 4.5; chitosan and sodium alginate are dissolved in an appropriate amount of acetic acid solution, ultrasonically dispersed until uniform, and Ca 2＋ Cross-linking to form a chitosan / sodium alginate double network gel composite system; Step 1.2: Build a response mechanism; In a slightly acidic environment of pH 5.5-6.5 on the wound surface, the carboxyl groups of sodium alginate in the double-network gel composite system are protonated, and the swelling degree increases from 150% to 300%. The network swells and releases Bletilla striata polysaccharide. The amino groups of chitosan are protonated, enhancing electrostatic adsorption with blood cells and accelerating coagulation. Step 2: Loading and releasing of Bletilla striata polysaccharide; Step 2.1, loading method of Bletilla striata polysaccharide; 80-90 wt% of Bletilla striata polysaccharide is blended with the double network gel composite system and fixed in the porous structure of the double network gel composite system by freeze drying; Step 2.2, release method of Bletilla striata polysaccharide; In a slightly acidic wound environment of pH 5.5-6.5, the release rate of Bletilla striata polysaccharide is >80% within 24 hours, achieving targeted controlled release. Under the neutral pH 7.4 environment of the wound surface, the release rate of Bletilla striata polysaccharide is less than 30% within 24 hours, achieving targeted controlled release; Step 3: Optimize the conductive function; Step 3.1, constructing a conductive path; Materials: Tea polyphenol modified graphene (Tp-rgo); Graphene modified with tea polyphenols is dispersed in a double-network gel composite system. During the freeze-drying process, the graphene is distributed along the direction of the ice crystals to form a continuous conductive path with an electrical conductivity of 10-3S / cm. Step 3.2, electrical stimulation coordination; A weak current of 0.1-0.5 mA activates the wound surface to achieve Ca 2＋ signaling pathway, promoting fibroblast migration and increasing the migration rate by 40%.

[0009] The present invention also has the following additional technical features: As a further specific optimization of the technical solution of the present invention: in step 1.1, a 2% CaCl2 solution is used to construct a double-network gel composite system.

[0010] As a further specific optimization of the technical solution of the present invention: in step 2 of loading and releasing Bletilla striata polysaccharide, the Bletilla striata polysaccharide extraction method is: the Bletilla striata slices are soaked in rice water for 6 hours, dynamically extracted with water at 50°C for 2 hours, the extract is allowed to stand at 4°C for 12 hours, and centrifuged and freeze-dried to obtain Bletilla striata polysaccharide with a purity of >90%.

[0011] As a further specific optimization of the technical solution of the present invention: in step 3.1, in constructing the conductive path, the freeze-drying process is directional freezing at -30°C for 12 hours and vacuum freeze-drying for 48 hours to form a porous sponge with a porosity of 92% and a pore size of 50-200 μm.

[0012] Compared with the prior art, the present invention has the following advantages: A novel method for preparing a hemostatic sponge aims to achieve more efficient and safer hemostasis by constructing a pH-responsive network system, loading it with Bletilla striata polysaccharide, and optimizing its electrical conductivity. This method not only offers a simple and cost-effective preparation process, but also produces a hemostatic sponge with excellent biocompatibility, degradability, and hemostatic properties, promising future development in the field of hemostatic materials. DETAILED DESCRIPTION Example

[0013] A method for preparing a novel hemostatic sponge comprises the following steps: Step 1: Construction of pH-responsive network system; Step 1.1, constructing a double network gel composite system: Materials: chitosan, sodium alginate and acetic acid solution; wherein, the deacetylation degree of chitosan is ≥90%, the mass ratio of chitosan to sodium alginate is 1:1, and the pH of the acetic acid solution is 4.5; chitosan and sodium alginate are dissolved in an appropriate amount of acetic acid solution, ultrasonically dispersed for 30 minutes until uniform, and then stirred by Ca 2＋ Cross-linking to form a chitosan / sodium alginate double network gel composite system; Step 1.2: Build a response mechanism; In a slightly acidic environment of pH 5.5-6.5 on the wound surface, the carboxyl groups of sodium alginate in the double-network gel composite system are protonated, and the swelling degree increases from 150% to 300%. The network swells and releases Bletilla striata polysaccharide. The amino groups of chitosan are protonated, enhancing electrostatic adsorption with blood cells and accelerating coagulation. Step 2: Loading and releasing of Bletilla striata polysaccharide; Step 2.1, loading method of Bletilla striata polysaccharide; 80-90 wt% of Bletilla striata polysaccharide is blended with the double network gel composite system and fixed in the porous structure of the double network gel composite system by freeze drying; Step 2.2, release method of Bletilla striata polysaccharide; In a slightly acidic wound environment of pH 5.5-6.5, the release rate of Bletilla striata polysaccharide is >80% within 24 hours, achieving targeted controlled release. Under the neutral pH 7.4 environment of the wound surface, the release rate of Bletilla striata polysaccharide is less than 30% within 24 hours, achieving targeted controlled release; Step 3: Optimize the conductive function; Step 3.1, constructing a conductive path; Materials: Tea polyphenol modified graphene (Tp-rgo); Graphene modified with tea polyphenols is dispersed in a double-network gel composite system. During the freeze-drying process, the graphene is distributed along the direction of the ice crystals to form a continuous conductive path with an electrical conductivity of 10-3S / cm. Step 3.2, electrical stimulation coordination; A weak current of 0.1-0.5 mA activates the wound surface to achieve Ca 2＋ signaling pathway, promoting fibroblast migration and increasing the migration rate by 40%. Example

[0014] Extraction of polysaccharide from Bletilla striata and preparation of composite sol.

[0015] 1. Extraction of polysaccharide from Bletilla striata: The Bletilla striata slices were soaked in rice water (pH 6.5) for 6 hours, and subjected to dynamic water extraction (containing 0.1% cellulase, solid-liquid ratio 1:30) at 50°C for 2 hours. The extract was allowed to stand at 4°C for 12 hours and centrifuged and freeze-dried to obtain Bletilla striata polysaccharide (purity > 90%).

[0016] 2. Preparation of composite sol: Bletilla striata polysaccharide (8% w / v), chitosan (4% w / v), sodium alginate (4% w / v), and TP-rGO (1 wt%) were dissolved in 1% acetic acid solution and ultrasonically dispersed (200 W, 30 min) until uniform. Example

[0017] Hemostatic sponge molding and performance testing.

[0018] 1. Ionic cross-linking and freeze-drying: The sol was injected into a mold, immersed in a 2% CaCl2 solution for cross-linking for 10 minutes, directionally frozen at -30°C for 12 hours, and freeze-dried in a vacuum for 48 hours to form a porous sponge (porosity 92%, pore size 50-200 μm).

[0019] 2. pH response release verification: The sponge was immersed in pH 5.5 buffer, and HPLC detection showed that the release rate of Bletilla striata polysaccharide was 82% in 24 hours (28% at pH 7.4).

[0020] 3. Animal Experimentation The wound surface of rat skin defect was covered with the drug, and the healing rate was 90% in 7 days (65% in the control group). Histology showed that collagen was arranged in an orderly manner and inflammatory factors (TNF-a) were reduced by 60%.

Claims

1. A method for preparing a novel hemostatic sponge, characterized in that: The following steps are included: Step 1: Construction of pH-responsive network system; Step 1.1, constructing a double network gel composite system: Materials: chitosan, sodium alginate and acetic acid solution; wherein, the deacetylation degree of chitosan is ≥90%, the mass ratio of chitosan to sodium alginate is 1:1, and the pH of the acetic acid solution is 4.5; chitosan and sodium alginate are dissolved in an appropriate amount of acetic acid solution, ultrasonically dispersed until uniform, and Ca 2＋ Cross-linking to form a chitosan / sodium alginate double network gel composite system; Step 1.2: Build a response mechanism; In a slightly acidic environment of pH 5.5-6.5 on the wound surface, the carboxyl groups of sodium alginate in the double-network gel composite system are protonated, and the swelling degree increases from 150% to 300%. The network swells and releases Bletilla striata polysaccharide. The amino groups of chitosan are protonated, enhancing electrostatic adsorption with blood cells and accelerating coagulation. Step 2: Loading and releasing of Bletilla striata polysaccharide; Step 2.1, loading method of Bletilla striata polysaccharide; 80-90 wt% of Bletilla striata polysaccharide is blended with the double network gel composite system and fixed in the porous structure of the double network gel composite system by freeze drying; Step 2.2, release method of Bletilla striata polysaccharide; In a slightly acidic wound environment of pH 5.5-6.5, the release rate of Bletilla striata polysaccharide is >80% within 24 hours, achieving targeted controlled release. Under the neutral pH 7.4 environment of the wound surface, the release rate of Bletilla striata polysaccharide is less than 30% within 24 hours, achieving targeted controlled release; Step 3: Optimize the conductive function; Step 3.1, constructing a conductive path; Materials: Tea polyphenol modified graphene (Tp-rgo); Graphene modified with tea polyphenols is dispersed in a double-network gel composite system. During the freeze-drying process, the graphene is distributed along the direction of the ice crystals to form a continuous conductive path with an electrical conductivity of 10-3S / cm. Step 3.2, electrical stimulation coordination; A weak current of 0.1-0.5 mA activates the wound surface to achieve Ca 2＋ signaling pathway, promoting fibroblast migration and increasing the migration rate by 40%.

2. The method for preparing the novel hemostatic sponge according to claim 1, wherein: In step 1.1, a 2% CaCl2 solution was used to construct the double network gel composite system.

3. The method for preparing the novel hemostatic sponge according to claim 1, wherein: In step 2, the loading and release of Bletilla striata polysaccharide, the extraction method of Bletilla striata polysaccharide is as follows: the Bletilla striata slices are soaked in rice water for 6 hours, dynamically extracted with water at 50°C for 2 hours, the extract is allowed to stand at 4°C for 12 hours, and centrifuged and freeze-dried to obtain Bletilla striata polysaccharide with a purity of >90%.

4. The method for preparing the novel hemostatic sponge according to claim 1, wherein: In step 3.1, in constructing the conductive path, the freeze-drying process is directional freezing at -30°C for 12 hours and vacuum freeze-drying for 48 hours to form a porous sponge with a porosity of 92% and a pore size of 50-200 μm.