A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction and a preparation method thereof

Abstract

The present application relates to a kind of composite biomaterial for quick hemostasis and bone regeneration after tooth extraction and its preparation method.The composite biomaterial for quick hemostasis and bone regeneration after tooth extraction of the present application includes: dialdehyde starch, chitosan-o-diphenol, gelatin, PRP-loaded response material PEG-SS.Dialdehyde starch, chitosan-o-diphenol and gelatin synergistic effect, can quickly realize physical compression hemostasis, while adding PRP-loaded response material PEG-SS, can realize the slow release of growth factor, extend hemostatic effect, and can support bone regeneration.Further optimization in combination with preparation method, preparation as powder, can be directly filled, and swelling effect is good, hemostasis is fast, can provide long-acting hemostasis and healing support.

Description

Technical Field

[0001] This invention relates to the field of biomaterials, and in particular to a composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, and its preparation method. Background Technology

[0002] Post-extraction hemostasis and bone regeneration are particularly important in dentistry. Tooth extraction exposes and damages the alveolar bone, making it prone to bleeding, infection, and poor bone healing post-operatively. This is especially true for patients planning to undergo dental implant surgery, as the health of the alveolar bone directly affects the stability and long-term function of the implant. However, traditional hemostasis methods, such as physical compression and local application of hemostatic drugs, usually only provide short-term hemostasis and are unlikely to effectively promote bone regeneration at the extraction site.

[0003] Currently, the main products on the market for hemostasis and bone regeneration after tooth extraction include:

[0004] 1. Fibrin Sponge: Fibrin sponge is a medical hemostatic material with good biocompatibility and water absorption and swelling properties. It achieves rapid hemostasis by binding with clotting factors in the blood. However, fibrin sponge mainly provides physical hemostasis and cannot promote bone tissue regeneration.

[0005] 2. Gelatin sponge: Gelatin sponge swells to form a gel after absorbing water, which can physically compress wounds to achieve short-term hemostasis and can be gradually absorbed by the body. Its main limitation is physical hemostasis and it cannot support long-term bone regeneration.

[0006] 3. Topical application of PRP: PRP is obtained from the patient's own blood through centrifugation and contains abundant growth factors (such as PDGF, TGF-β, VEGF, etc.), which have the potential to promote angiogenesis and bone tissue regeneration. However, liquid PRP is difficult to remain at the wound site for a long time and is easily lost with blood or saliva. Furthermore, the release rate of growth factors is difficult to control, making it difficult to achieve long-term bone regeneration support.

[0007] However, these existing products have limitations in hemostasis. For example, some materials lack structural stability, easily softening or disintegrating after absorbing water and swelling. Their poor mechanical strength also prevents them from providing long-term, stable hemostatic support in the dynamic oral environment. They only offer short-term hemostasis, which is insufficient in complex tooth extraction procedures, easily leading to secondary bleeding. Furthermore, these traditional hemostatic materials are primarily focused on hemostasis and do not provide adequate support for alveolar bone regeneration, especially when bone resorption or poor healing occurs at the extraction site, potentially affecting the stability of subsequent implants. While PRP is rich in growth factors, the uncontrolled release of these factors results in insufficient duration of action, also impacting bone regeneration. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention proposes a composite biomaterial based on bis(aldehyde) starch (CMS), chitosan, gelatin, PRP, and the smart responsive material PEG-SS. This composite material can effectively achieve rapid hemostasis after tooth extraction and promote bone tissue regeneration, with a long-lasting and stable effect.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] In a first aspect, the present invention provides a composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, the raw materials of which include: dialdehyde starch, chitosan-catechol, gelatin, and PEG-SS responsive material loaded with PRP.

[0011] The composite material, consisting of dialdehyde starch, chitosan-catechol, and gelatin, works synergistically to achieve physical compression hemostasis. The addition of PEG-SS (polyethylene glycol disulfide bond), a responsive material loaded with PRP, enables the slow release of growth factors and provides sustained support for bone regeneration. This composite material offers long-lasting hemostasis while also supporting bone regeneration. It can be formulated into common hemostatic material forms such as gels, sponges, and powders.

[0012] In some other embodiments, the PRP-loaded responsive material PEG-SS is obtained by dispersing PRP and PEG-SS in a solvent, stirring until homogeneous, centrifuging, and freeze-drying. Preferably, the mass ratio of PRP to PEG-SS is 1:4 to 5.

[0013] The composite bone regeneration material of this invention can be a gel prepared from the above-mentioned materials, or a freeze-dried sponge product, etc.; preferably, the composite biomaterial of this invention is a powder prepared by freeze-drying the gel obtained from the raw materials. When used, it can be directly filled into the tooth extraction socket to swell and achieve hemostasis, and it is also convenient for production, transportation, and storage.

[0014] Preferably, the gel contains, by weight-volume concentration, 1-4% dialdehyde starch, 0.5-1.25% chitosan-catechol, 2.5-5% gelatin, and 2.5-5% PEG-SS responsive material loaded with PRP. More preferably, the gel contains, by weight-volume concentration, 1.25-4% dialdehyde starch, 0.8-1.25% chitosan-catechol, 3.5-5% gelatin, and 4-5% PEG-SS responsive material loaded with PRP.

[0015] Preferably, the particle size of the composite biomaterial is 100-200 micrometers. It exhibits rapid swelling, facilitating better filling.

[0016] The present invention also provides a method for preparing the aforementioned composite biomaterial, comprising the following steps:

[0017] Gelatin solution, chitosan-catechol solution, and dialdehyde starch solution were mixed and dripped into PEG-SS responsive material loaded with PRP. The mixture was stirred until homogeneous and then allowed to stand to obtain the gel.

[0018] Preferably, the gelatin solution, chitosan-catechol solution, and dialdehyde starch solution are prepared by dissolving gelatin, chitosan-catechol, and dialdehyde starch in pure water or PBS buffer, respectively.

[0019] Preferably, the concentration of the dialdehyde starch solution is 0.02–0.08 g / mL; the concentration of the chitosan-catechol solution is 0.02–0.05 g / mL; and the concentration of the gelatin solution is 0.1–0.2 g / mL.

[0020] Preferably, the volume ratio of gelatin solution: chitosan-catechol solution: dialdehyde starch solution is 1:1:2.

[0021] Compared with the prior art, the present invention has the following beneficial and unique effects:

[0022] In this invention, a composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction utilizes dialdehyde starch, chitosan-catechol, and gelatin to synergistically absorb water and swell to form a gel, rapidly achieving physical compression hemostasis. Simultaneously, the addition of PEG-SS, a responsive material loaded with PRP, enables the slow release of growth factors, prolonging the hemostatic effect and supporting bone regeneration. Furthermore, through optimized preparation methods, it is formulated as a powder for direct filling, exhibiting good swelling effect, rapid hemostasis, and high material strength, providing long-lasting hemostasis and healing support. Detailed Implementation

[0023] The present invention will be further illustrated below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in this technical field.

[0024] Unless otherwise specified, all reagents and materials used in the following examples are commercially available.

[0025] Example 1

[0026] A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, comprising the following raw materials: dialdehyde starch, chitosan-catechol, gelatin, and PEG-SS responsive material loaded with PRP.

[0027] Its preparation method includes the following steps:

[0028] 1. Preparation of dialdehyde starch:

[0029] Dissolve 2g of dialdehyde starch in 100mL of PBS buffer and stir at 60℃ for 12 hours to prepare a 2% solution.

[0030] 2. Preparation of chitosan-catechol solution:

[0031] Dissolve 2g of chitosan-catechol in 100mL of PBS buffer to prepare a 2% chitosan-catechol solution.

[0032] 3. Preparation of gelatin solution:

[0033] Dissolve 10g of gelatin in 100mL of pure water and stir at 50℃ for 1 hour to prepare a 10% solution.

[0034] 4. Preparation of responsive PRP release carriers:

[0035] Dissolve 0.2 g PRP and 0.8 g PEG-SS in 10 mL PBS buffer, stir at 4 °C for 24 hours, centrifuge at 8000 rpm for 10 minutes, collect the precipitate, freeze dry, and obtain PEG-SS@PRP.

[0036] 5. Preparation of powder:

[0037] Place 0.5g of PEG-SS@PRP powder in a beaker, then add 5mL of gelatin solution, 5mL of chitosan-catechol, and 10mL of dialdehyde starch solution dropwise into the beaker at a rate of 5mL / min, while mechanically stirring at 500rpm / min. After all the liquids have been completely added, continue stirring for 30 minutes to ensure that all components are completely mixed. Remove the stirring and let stand at room temperature for 24 hours to form a gel.

[0038] The fully gelled colloid was freeze-dried and then pulverized in a mechanical grinder. The particle size range of the pulverized material was controlled to be 100-200 micrometers. The pulverized material was then sieved using 100-mesh and 200-mesh sieves to ensure that the powder particle size distribution was uniform and reached the target particle size range.

[0039] Example 2

[0040] A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, comprising the following raw materials: dialdehyde starch, chitosan-catechol, gelatin, and PEG-SS responsive material loaded with PRP.

[0041] Its preparation method includes the following steps:

[0042] 1. Preparation of dialdehyde starch:

[0043] Dissolve 5g of dialdehyde starch in 100mL of PBS buffer and stir at 70℃ for 12 hours to prepare a 5% solution.

[0044] 2. Preparation of chitosan-catechol solution:

[0045] Dissolve 3.5g of chitosan-catechol in 100mL of PBS buffer to prepare a 3.5% chitosan-catechol solution.

[0046] 3. Preparation of gelatin solution:

[0047] Dissolve 15g of gelatin in 100mL of pure water and stir at 50℃ for 1 hour to prepare a 15% solution.

[0048] 4. Preparation of responsive PRP release carriers:

[0049] Dissolve 0.2g PRP and 1g PEG-SS in 10mL PBS buffer, stir at 4℃ for 24 hours, centrifuge at 10000rpm for 15 minutes, collect the precipitate, freeze dry, and obtain PEG-SS@PRP.

[0050] 5. Preparation of powder:

[0051] Place 0.8g of PEG-SS@PRP powder in a beaker, then add 5mL of gelatin solution, 5mL of chitosan-catechol, and 10mL of dialdehyde starch solution dropwise into the beaker at a rate of 5mL / min, while mechanically stirring at 500rpm / min. After all the liquids have been completely added, continue stirring for 30 minutes to ensure that all components are completely mixed. Remove the stirring and let stand at room temperature for 24 hours to form a gel.

[0052] The fully gelled colloid was freeze-dried and then pulverized in a mechanical grinder. The particle size range of the pulverized material was controlled to be 100-200 micrometers. The pulverized material was then sieved using 100-mesh and 200-mesh sieves to ensure that the powder particle size distribution was uniform and reached the target particle size range.

[0053] Example 3

[0054] A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, comprising the following raw materials: dialdehyde starch, chitosan-catechol, gelatin, and PEG-SS responsive material loaded with PRP.

[0055] Its preparation method includes the following steps:

[0056] 1. Preparation of dialdehyde starch:

[0057] Dissolve 8g of dialdehyde starch in 100mL of PBS buffer and stir at 90℃ for 10 hours to prepare an 8% solution.

[0058] 2. Preparation of chitosan-catechol solution:

[0059] Dissolve 5g of chitosan-catechol in 100mL of PBS buffer to prepare a 5% chitosan-catechol solution.

[0060] 3. Preparation of gelatin solution:

[0061] Dissolve 20g of gelatin in 100mL of pure water and stir at 50℃ for 1 hour to prepare a 20% solution.

[0062] 4. Preparation of responsive PRP release carriers:

[0063] Dissolve 0.2g PRP and 1g PEG-SS in 10mL PBS buffer, stir at 4℃ for 24 hours, centrifuge at 10000rpm for 15 minutes, collect the precipitate, freeze dry, and obtain PEG-SS@PRP.

[0064] 5. Preparation of powder:

[0065] Place 1g of PEG-SS@PRP powder in a beaker, then add 5mL of gelatin solution, 5mL of chitosan-catechol, and 10mL of dialdehyde starch solution dropwise into the beaker at a rate of 5mL / min, while mechanically stirring at 500rpm / min. After all the liquids have been completely added, continue stirring for 30 minutes to ensure that all components are completely mixed. Remove the stirring and let stand at room temperature for 24 hours to form a gel.

[0066] The fully gelled colloid was freeze-dried and then pulverized in a mechanical grinder. The particle size range of the pulverized material was controlled to be 100-200 micrometers. The pulverized material was then sieved using 100-mesh and 200-mesh sieves to ensure that the powder particle size distribution was uniform and reached the target particle size range.

[0067] Comparative Example 1

[0068] A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, the raw materials of which include: chitosan-catechol and gelatin.

[0069] Its preparation method includes the following steps:

[0070] 1. Preparation of chitosan-catechol solution:

[0071] Dissolve 25g of chitosan-catechol in 100mL of PBS buffer to prepare a 5% chitosan-catechol solution.

[0072] 2. Preparation of gelatin solution:

[0073] Dissolve 20g of gelatin in 100mL of pure water and stir at 50℃ for 1 hour to prepare a 20% solution.

[0074] 3. Mixing and molding of hemostatic materials:

[0075] Add 5 mL of gelatin solution and 5 mL of chitosan-catechol to a beaker at a rate of 5 mL / min, while mechanically stirring at 500 rpm / min. After all the liquids have been added, continue stirring for 30 minutes to ensure that all components are completely mixed. Remove the stirring and let stand at room temperature for 24 hours to form a gel.

[0076] The fully gelled colloid was freeze-dried and then pulverized in a mechanical grinder. The particle size range of the pulverized material was controlled to be 100-200 micrometers. The pulverized material was then sieved using 100-mesh and 200-mesh sieves to ensure that the powder particle size distribution was uniform and reached the target particle size range.

[0077] Comparative Example 2

[0078] A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, the raw materials of which include: dialdehyde starch and chitosan-catechol.

[0079] Its preparation method includes the following steps:

[0080] 1. Preparation of dialdehyde starch:

[0081] Dissolve 8g of dialdehyde starch in 100mL of PBS buffer and stir at 90℃ for 10 hours to prepare an 8% solution.

[0082] 2. Preparation of chitosan-catechol solution:

[0083] Dissolve 5g of chitosan-catechol in 100mL of PBS buffer to prepare a 5% chitosan-catechol solution.

[0084] 3. Preparation of powder:

[0085] Add 5 mL of chitosan-catechol and 10 mL of dialdehyde starch solution to a beaker at a rate of 5 mL / min, while mechanically stirring at 500 rpm / min. After all the liquids have been added, continue stirring for 30 minutes to ensure that all components are completely mixed. Remove the stirring and let stand at room temperature for 24 hours to form a gel.

[0086] The fully gelled colloid was freeze-dried and then pulverized in a mechanical grinder. The particle size range of the pulverized material was controlled to be 100-200 micrometers. The pulverized material was then sieved using 100-mesh and 200-mesh sieves to ensure that the powder particle size distribution was uniform and reached the target particle size range.

[0087] Comparative Example 3

[0088] A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, the raw materials of which include: dialdehyde starch and gelatin.

[0089] Its preparation method includes the following steps:

[0090] 1. Preparation of dialdehyde starch:

[0091] Dissolve 8g of dialdehyde starch in 100mL of PBS buffer and stir at 90℃ for 10 hours to prepare an 8% solution.

[0092] 2. Preparation of gelatin solution:

[0093] Dissolve 20g of gelatin in 100mL of pure water and stir at 50℃ for 1 hour to prepare a 20% solution.

[0094] 3. Preparation of powder:

[0095] Add 5 mL of gelatin solution and 10 mL of dialdehyde starch solution dropwise into a beaker at a rate of 5 mL / min, while mechanically stirring at 500 rpm / min. After all the liquids have been added, continue stirring for 30 minutes to ensure that all components are completely mixed. Remove the stirring and let stand at room temperature for 24 hours to form a gel.

[0096] The fully gelled colloid was freeze-dried and then pulverized in a mechanical grinder. The particle size range of the pulverized material was controlled to be 100-200 micrometers. The pulverized material was then sieved using 100-mesh and 200-mesh sieves to ensure that the powder particle size distribution was uniform and reached the target particle size range.

[0097] Comparative Example 4

[0098] A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, the raw materials of which include: dialdehyde starch, chitosan-catechol, and gelatin.

[0099] Its preparation method includes the following steps:

[0100] 1. Preparation of dialdehyde starch:

[0101] Dissolve 8g of dialdehyde starch in 100mL of PBS buffer and stir at 90℃ for 10 hours to prepare an 8% solution.

[0102] 2. Preparation of chitosan-catechol solution:

[0103] Dissolve 5g of chitosan-catechol in 100mL of PBS buffer to prepare a 5% chitosan-catechol solution.

[0104] 3. Preparation of gelatin solution:

[0105] Dissolve 20g of gelatin in 100mL of pure water and stir at 50℃ for 1 hour to prepare a 20% solution.

[0106] 4. Preparation of powder:

[0107] Add 5 mL of gelatin solution, 5 mL of chitosan-catechol solution, and 10 mL of dialdehyde starch solution dropwise into a beaker at a rate of 5 mL / min, while mechanically stirring at 500 rpm / min. After all the liquids have been added, continue stirring for 30 minutes to ensure that all components are completely mixed. Remove the stirring and let stand at room temperature for 24 hours to form a gel.

[0108] The fully gelled colloid was freeze-dried and then pulverized in a mechanical grinder. The particle size range of the pulverized material was controlled to be 100-200 micrometers. The pulverized material was then sieved using 100-mesh and 200-mesh sieves to ensure that the powder particle size distribution was uniform and reached the target particle size range.

[0109] Comparative Example 5

[0110] A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, the raw materials of which include: dialdehyde starch, chitosan-catechol, and gelatin.

[0111] Its preparation method includes the following steps:

[0112] 1. Preparation of dialdehyde starch:

[0113] Dissolve 8g of dialdehyde starch in 100mL of PBS buffer and stir at 90℃ for 10 hours to prepare an 8% solution.

[0114] 2. Preparation of chitosan-catechol solution:

[0115] Dissolve 5g of chitosan-catechol in 100mL of PBS buffer to prepare a 5% chitosan-catechol solution.

[0116] 3. Preparation of gelatin solution:

[0117] Dissolve 20g of gelatin in 100mL of pure water and stir at 50℃ for 1 hour to prepare a 20% solution.

[0118] 4. Preparation of powder:

[0119] Place 0.2g of PRP solution in a beaker, then add 5mL of gelatin solution, 5mL of chitosan-catechol, and 10mL of dialdehyde starch solution dropwise into the beaker at a rate of 5mL / min, while mechanically stirring at 500rpm / min. After all the liquids have been completely added, continue stirring for 30 minutes to ensure that all components are completely mixed. Remove the stirring and let stand at room temperature for 24 hours to form a gel.

[0120] The fully gelled colloid was freeze-dried and then pulverized in a mechanical grinder. The particle size range of the pulverized material was controlled to be 100-200 micrometers. The pulverized material was then sieved using 100-mesh and 200-mesh sieves to ensure that the powder particle size distribution was uniform and reached the target particle size range.

[0121] Comparative Example 6

[0122] Absorbent gelatin sponge produced by Jiangxi Xiang'en Medical Technology Development Co., Ltd.

[0123] Performance testing:

[0124] 1. Measurement of hemostasis time

[0125] Experimental Methods: A rat tail vein incision model was used to simulate bleeding after tooth extraction. Hemostatic powder was applied directly to the incision site, and the time required for complete cessation of bleeding was recorded. The same test was performed on both the experimental and control groups. The experiment was repeated multiple times to obtain statistical significance, and the average hemostasis time was recorded.

[0126] Table 1 Results of hemostatic effect test

[0127]

[0128] The test results are shown in Table 1. In Examples 1-3, as the proportions of dialdehyde starch, chitosan-catechol, and gelatin increased, the hemostatic effect was enhanced, and the bleeding was reduced. Furthermore, combining the results of Example 3 and Comparative Examples 1-3, it can be seen that dialdehyde starch, chitosan-catechol, and gelatin all have a certain promoting effect on the hemostatic effect; the three work synergistically to reduce hemostasis time and bleeding. Moreover, compared to the commercially available gelatin sponge in Comparative Example 6, the sample from the present invention exhibits a faster hemostatic ability.

[0129] 2. Material stability

[0130] Experimental Method: Take 200 mg of dry composite material powder and add 100 μL of PBS buffer to allow it to gel completely. Place the sample in a container with PBS buffer (pH 7.4) and let it stand in a 37°C water bath for 8 hours to simulate the human oral cavity environment. Take the water-absorbed and swollen sample and press it with a 5 g weight for 5 minutes to simulate the pressure in the oral cavity environment, and observe the structural integrity of the material. Observe the morphology of the water-absorbed and swollen material with the naked eye and record whether the sample disintegrates, excessively softens, or develops surface cracks.

[0131] Table 2. Results of Material Stability Tests

[0132]

[0133] The test results are shown in Table 2. Examples 1-3 exhibited significant stability due to the favorable blending ratio of dialdehyde starch, chitosan-catechol, and gelatin. Comparative Example 1, lacking dialdehyde starch as a cross-linking agent, was structurally unstable and rapidly disintegrated under pressure after absorbing water and swelling. Comparative Examples 2 and 3, lacking gelatin and chitosan-catechol respectively, ultimately showed slight disintegration and micro-cracks. This demonstrates that the blending of these three components is essential for maintaining the stability of the hemostatic gel.

[0134] 3. Release time of PDGF growth factor in PRP

[0135] Experimental method: 200 mg of powder was premixed with 100 μL of PBS buffer to form a gel. The gel was then placed in PBS, PBS containing 1% hydrogen peroxide (H2O2), and PBS containing 0.1% hydrogen peroxide (H2O2), and the longest release time of PDGF in PRP was recorded.

[0136] Table 3 Release time of growth factor PDGF in PRP

[0137] Example 3 Comparative Example 5 PBS 28 days 5 days <![CDATA[PBS(1%H2O2)]]> 5 days 2 days <![CDATA[PBS(0.1%H2O2)]]> 12 days 3 days

[0138] The test results are shown in Table 3. PEG-SS-encapsulated PRP can achieve long-term sustained release in a PBS environment. In a hydrogen peroxide environment, the release rate accelerates due to the generation of ROS; the higher the ROS level, the faster the release rate. This indicates that PEG-SS@PRP can achieve ROS-controlled release in response to damage.

[0139] 4. Bone regeneration effect (Micro-CT bone mass)

[0140] Experimental Methods: 200 mg of powder was premixed with 100 μL of PBS buffer to form an implantation gel. Rats were anesthetized by intraperitoneal injection of sodium pentobarbital. After confirming sufficient anesthesia depth, the hair on the back was shaved and the area was disinfected. A small incision was made at the designated subcutaneous location, and the subcutaneous tissue was separated to form an implantation cavity. The material was placed in the cavity, and the incision was sutured. Postoperatively, the rats were placed on a warming pad to recover from anesthesia and closely observed. Antibiotics were administered as needed to prevent infection. Eight weeks after implantation, a sample containing osteogenic material and surrounding tissue was collected and fixed in 4% paraformaldehyde solution. Subsequently, the fixed sample was placed in a Micro-CT sample tube to ensure sample stability, and a 360° omnidirectional scan was performed using a resolution of 10-20 μm. After scanning, three-dimensional reconstruction was performed on the image data. The newly formed bone region was segmented on the reconstructed image, and bone density, newly formed bone volume (BV), and total scan volume (TV) were measured. Finally, the effect of ectopic osteogenic formation was quantified using BV / TV data.

[0141] Table 4 Results of bone regeneration effect test

[0142]

[0143]

[0144] The test results are shown in Table 4. The data shows that the osteogenic effect of PRP sustained release in Example 3 is significantly better than that of PRP burst release in Comparative Example 5, and even better than the commercially available gelatin sponge in Comparative Example 5.

[0145] 5. Biocompatibility (cell viability)

[0146] Experimental Methods: Cytotoxicity assays were performed using mouse fibroblasts (L929). The material extract and cells were co-cultured for 24 hours. Cell viability was assessed using the CCK-8 assay, and cell survival rate was determined. The experiment was repeated three times, and the mean value was used. Cell survival rates were compared between the experimental and control groups to evaluate the biocompatibility of the material.

[0147] Table 5. Results of cell viability testing

[0148]

[0149] The test results are shown in Table 5. Examples 1-3 and Comparative Examples 1 and 5 all exhibited high cell viability (>90%), demonstrating good biocompatibility and suitability for biomedical materials. The cell viability of Comparative Examples 2-6 decreased slightly. This may be because the addition of gelatin and PRP protected cell survival.

[0150] 6. Antibacterial properties

[0151] Experimental method: The material was placed on a culture medium containing bacteria (such as Escherichia coli and Staphylococcus aureus) and incubated for 24 hours. The inhibition zone around the material was then observed. The antibacterial properties of the material were quantitatively evaluated by measuring the diameter of the inhibition zone.

[0152] Table 6. Results of Antibacterial Performance Tests

[0153]

[0154] The test results are shown in Table 6. As the amount of dialdehyde starch, chitosan-catechol and gelatin increased, the area of ​​the inhibition zone increased. Among them, chitosan-catechol had the greatest antibacterial effect, while other components such as gelatin and dialdehyde starch also made some contributions.

[0155] In summary, the composite material prepared by compounding dialdehyde starch, chitosan-catechol, and gelatin in the embodiments of the present invention exhibits good gelation properties after swelling, demonstrating excellent hemostatic effects. Furthermore, the introduction of the PRP-loaded smart responsive material PEG-SS provides a sustained-release effect, promoting bone regeneration. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A composite biomaterial for rapid hemostasis and bone regeneration after tooth extraction, characterized in that, Its raw materials include: dialdehyde starch, chitosan-catechol, gelatin, and PEG-SS, a responsive material loaded with PRP; The PRP-loaded responsive material PEG-SS is obtained by dispersing PRP and PEG-SS in a solvent, stirring until uniform, centrifuging, and freeze-drying. The mass ratio of PRP to the responsive material PEG-SS is 1:4~5; The composite biomaterial is a powder prepared by freeze-drying a gel obtained from the raw materials. The gel contains, by mass-volume concentration, 1-4% dialdehyde starch, 0.5-1.25% chitosan-catechol, 2.5-5% gelatin, and 2.5-5% PEG-SS responsive material loaded with PRP.

2. The composite biomaterial according to claim 1, characterized in that, The particle size of the composite biomaterial is 100-200 micrometers.

3. The method for preparing the composite biomaterial according to claim 1 or 2, characterized in that, Including the following steps: Gelatin solution, chitosan-catechol solution, and dialdehyde starch solution were mixed and dripped into PEG-SS responsive material loaded with PRP. The mixture was stirred until homogeneous and then allowed to stand to obtain the gel.

4. The preparation method according to claim 3, characterized in that, The gelatin solution, chitosan-catechol solution, and dialdehyde starch solution are prepared by dissolving gelatin, chitosan-catechol, and dialdehyde starch in pure water or PBS buffer, respectively.

5. The preparation method according to claim 3, characterized in that, The concentration of the dialdehyde starch solution is 0.02~0.08 g / mL; the concentration of the chitosan-catechol solution is 0.02~0.05 g / mL; and the concentration of the gelatin solution is 0.1~0.2 g / mL.

6. The preparation method according to claim 3, characterized in that, According to the volume ratio, gelatin solution : chitosan-catechol solution : dialdehyde starch solution = 1:1:2.

Images