Keratin zeolite imidazole acid framework composite sponge with shape memory function and its preparation method and application

Abstract

A keratin zeolite imidazolate framework composite sponge with shape memory function, as well as its preparation method and application. The hemostatic sponge prepared by the present invention can timely treat non-compressible bleeding and prevent wound infection. Due to the excellent hemostatic performance of keratin, the porous structure of the sponge and the synergistic effect of metal ions released by zeolite imidazolate framework nanoparticles, the sponge has a significant hemostatic effect on different bleeding models. The present invention has good shape memory performance, biocompatibility, blood compatibility, excellent biosafety, antibacterial properties, etc., and shows great potential in clinical hemostasis and anti-infection and healing promotion.

Description

Technical Field

[0001] The invention relates to the technical field of hemostatic materials, and in particular to a keratin zeolite imidazole acid framework composite sponge with shape memory function, a preparation method and an application thereof. Background Art

[0002] Cardiovascular failure, tissue hypoxia, ischemia, and organ dysfunction caused by uncontrolled massive bleeding are the leading causes of death in both warfare and life. Most of these deaths occur in the harsh environments of hospitalization or before surgical treatment. To date, a variety of hemostatic materials have been researched and developed, including hemostatic bandages, gauze, zeolite, chitosan-based powders, and gelatin-based sponges. However, these hemostatic materials have limitations when applied to uncontrolled massive bleeding wounds on the battlefield or in real life. For example, they cannot be delivered to irregularly shaped, non-compressible bleeding sites. Furthermore, wounds are susceptible to bacterial infection after prolonged exposure to air. Therefore, it is crucial for researchers to develop a new multifunctional hemostatic material that can quickly and effectively control massive bleeding, kill bacteria, and accelerate wound healing.

[0003] Keratin, a naturally occurring protein found in animal tissues such as wool, skin, nails, and feathers, has garnered significant attention in recent years in the fields of hemostasis and wound healing. Keratin has been reported to promote hemostasis by significantly shortening plasma clotting lag time and increasing lateral fiber assembly, and its activity can be maintained under simulated coagulopathy conditions. However, as a hemostatic agent, keratin has limitations in its use for treating uncontrolled bleeding wounds. Keratin-based materials typically have low mechanical strength and lack the stability required for hemostatic applications. Furthermore, keratin lacks antimicrobial properties, limiting its effectiveness in combating the harsh environments encountered in hospitals or prior to surgery. Therefore, to broaden the application prospects of keratin as a hemostatic agent, it is necessary to find methods to overcome these shortcomings and even further enhance its hemostatic properties. Summary of the Invention

[0004] In order to solve the technical defects of the existing technology, the present invention provides a keratin zeolite imidazole acid framework composite sponge with shape memory function and its preparation method and application, which has excellent mechanical properties, good biocompatibility, rapid hemostasis speed, safe use, and certain antibacterial properties to kill bacteria and prevent wound infection.

[0005] The technical solution adopted by the present invention is: a keratin zeolite imidazolate framework composite sponge with shape memory function, the hemostatic sponge includes keratin material and a zeolite imidazolate framework, the zeolite imidazolate framework is one or more of ZIF-8 and ZIF-67, and the hemostatic sponge has a porous structure.

[0006] The keratin material is one or more of human hair keratin, feather keratin and wool keratin.

[0007] A method for preparing a keratin zeolite imidazole acid framework composite sponge with shape memory function comprises the following steps:

[0008] (1) Compound A and 2-methylimidazole were dissolved in methanol, respectively. The two solutions were mixed and stirred at room temperature. The mixture was centrifuged, and the powder particles were collected and washed with methanol to remove excess compound A and 2-methylimidazole. The washed powder particles were dried at 70°C for 12 h to obtain product A.

[0009] (2) Keratin material powder is dissolved in sodium sulfide nonahydrate solution and stirred to dissolve, and then product A is added in different mass ratios, and sodium dodecyl sulfate solution is added to the mixed solution. After foaming under high-speed rotation, it is frozen and freeze-dried. After freeze-drying, it is washed with deionized water and then freeze-dried to obtain the composite sponge material.

[0010] The compound A is one or more of zinc nitrate hexahydrate and cobalt nitrate hexahydrate.

[0011] The product A is a zeolite imidazolate framework material containing one or more of ZIF-8 and ZIF-67.

[0012] The keratin material is one or more of human hair keratin, feather keratin and wool keratin.

[0013] The keratin material powder is dissolved in the sodium sulfide nonahydrate solution to a concentration of 10 wt%.

[0014] The mass percentage of the product A in the keratin material powder is 10-50%.

[0015] The mass percentage of the product A to the mass of the keratin material powder is 0%, 10%, 30% and 50%.

[0016] The concentration of the sodium sulfide nonahydrate solution is 10 wt%

[0017] The mass percentage of the sodium lauryl sulfate in the keratin material powder is 5%.

[0018] The rotation speed of the high-speed stirring is 1500 rpm.

[0019] The freezing temperature is -80°C, and the freezing time is 2 h to 4 h.

[0020] Application of a keratin zeolite imidazole acid framework composite sponge with shape memory function in the preparation of hemostatic materials.

[0021] The present invention provides a keratin-zeolite imidazolate framework composite sponge with shape memory, as well as its preparation method and application. Combining the advantages of keratin and the zeolite imidazolate framework, supplemented by its self-swelling properties, it effectively seals bleeding wounds. The keratin-based material is used as the primary material, imparting excellent biocompatibility and promoting hemostasis. The zeolite imidazolate framework is incorporated into the keratin network. The metal ions released by the zeolite imidazolate framework enhance platelet aggregation and act as a cofactor to activate coagulation factor XII, thereby triggering the remaining intrinsic coagulation cascade, leading to the production of thrombin and fibrin. Experimental results demonstrate that the hemostatic sponge significantly promotes hemostasis in the liver and femoral arteries of mice and in the auricular artery and liver of rabbits. This invention thoroughly addresses the issues of long hemostatic duration and poor hemostatic efficacy associated with passive hemostatic materials, while also fundamentally improving the blood safety of active hemostatic materials. This invention is expected to improve the overall hemostatic performance of hemostatic sponge-based dressings. In addition, the hemostatic sponge has good biocompatibility, blood compatibility and antibacterial properties and will not cause hemolytic reactions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is an SEM image of the surface morphology of the shape memory keratin / zeolite imidazolate skeleton composite hemostatic sponge in the example.

[0023] Figure 2 The FI-TR spectra of the shape memory hemostatic sponges of the examples are as follows: (1) infrared spectrum of the product obtained after Example 1, (2) infrared spectrum of the product obtained after Example 2, (3) infrared spectrum of the product obtained after Example 3, and (4) infrared spectrum of the product obtained after Example 4.

[0024] Figure 3 It is the blood absorption ratio of the shape memory hemostatic sponge of the embodiment.

[0025] Figure 4 It is the shape recovery ratio of the shape memory hemostatic sponge of the embodiment.

[0026] Figure 5 It is the shape recovery time of the shape memory hemostatic sponge of the embodiment.

[0027] Figure 6 It is the whole blood coagulation index of the shape memory hemostatic sponge of the embodiment.

[0028] Figure 7 This is the whole blood clotting time of the shape memory hemostatic sponge in the embodiment.

[0029] Figure 8 It is the red blood cell adhesion rate of the shape memory hemostatic sponge in the embodiment.

[0030] Figure 9 This is a SEM image of the red blood cell adsorption of the shape memory hemostatic sponge of the embodiment.

[0031] Figure 10 It is the platelet adhesion rate of the shape memory hemostatic sponge in the embodiment.

[0032] Figure 11 This is a SEM image of platelet adsorption on the shape memory hemostatic sponge of the embodiment.

[0033] Figure 12 This is a diagram showing the anti-E. coli effect of the shape memory hemostatic sponge in the example.

[0034] Figure 13 This is a diagram showing the anti-Staphylococcus aureus effect of the shape memory hemostatic sponge in the embodiment.

[0035] Figure 14 The figures are as follows: The bleeding volume statistics of the shape memory hemostatic sponge in the rat femoral artery injury model.

[0036] Figure 15 The figures are as follows: The bleeding volume statistics of the shape memory hemostatic sponge in the rabbit ear artery injury model.

[0037] Figure 16 The figures are as follows: The bleeding volume statistics of the shape memory hemostatic sponge in the rat liver injury model.

[0038] Figure 17 The bleeding volume statistics of the shape memory hemostatic sponge in the rabbit liver injury model are shown in the following example.

[0039] Figure 18 This is an example of cytotoxicity analysis of shape memory hemostatic sponge. DETAILED DESCRIPTION

[0040] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0041] The present invention provides a composite hemostatic sponge with shape memory properties, excellent mechanical properties, good biocompatibility, rapid hemostasis, and safety. It also possesses antibacterial properties to kill bacteria and prevent wound infection. The sponge is composed of keratin and a zeolite imidazolate backbone, where the keratin is one or more of human hair keratin, feather keratin, and wool keratin; the zeolite imidazolate backbone is one or more of ZIF-8 and ZIF-67. The resulting hemostatic sponge has a white or yellow porous structure.

[0042] Example 1

[0043] (1) Dissolve 0.3 g of zinc nitrate hexahydrate and 0.66 g of 2-methylimidazole in 14.3 mL of methanol. The two solutions were mixed and stirred at room temperature (22°C) for 2 h. The mixture was centrifuged at 10,000 rpm for 10 min, and the powder particles were collected and washed three times with methanol to remove excess zinc nitrate and 2-methylimidazole. The washed powder particles were dried at 70°C for 12 h to obtain ZIF-8 powder.

[0044] (2) First, 0.1 g of wool keratin powder was dissolved in 1 mL of sodium sulfide nonahydrate solution (10 wt%) and stirred to dissolve. Then, 100 μL of sodium dodecyl sulfate solution was added, foamed under high-speed rotation (1500 rpm), and then frozen. Then, the mixture was placed in a freeze dryer for processing. After freeze-drying, it was washed with deionized water and then freeze-dried to obtain a hemostatic sponge material.

[0045] Example 2

[0046] (1) Dissolve 0.3 g of zinc nitrate hexahydrate and 0.66 g of 2-methylimidazole in 14.3 mL of methanol. The two solutions were mixed and stirred at room temperature (22°C) for 2 h. The mixture was centrifuged at 10,000 rpm for 10 min, and the powder particles were collected and washed three times with methanol to remove excess zinc nitrate and 2-methylimidazole. The washed powder particles were dried at 70°C for 12 h to obtain ZIF-8 powder.

[0047] (2) First, 0.1 g of wool keratin powder was dissolved in 1 mL of sodium sulfide nonahydrate solution (10 wt%) and stirred to dissolve. Then, 0.01 g of ZIF-8 powder was added. After that, 100 μL of sodium dodecyl sulfate solution was added to the mixed solution, foamed under high-speed rotation (1500 rpm), and then frozen. Then, the mixture was placed in a freeze dryer for processing. After freeze-drying, it was washed with deionized water and then freeze-dried to obtain a hemostatic sponge material.

[0048] Example 3

[0049] (1) Dissolve 0.3 g of zinc nitrate hexahydrate and 0.66 g of 2-methylimidazole in 14.3 mL of methanol. The two solutions were mixed and stirred at room temperature (22°C) for 2 h. The mixture was centrifuged at 10,000 rpm for 10 min, and the powder particles were collected and washed three times with methanol to remove excess zinc nitrate and 2-methylimidazole. The washed powder particles were dried at 70°C for 12 h to obtain ZIF-8 powder.

[0050] (2) First, 0.1 g of wool keratin powder was dissolved in 1 mL of sodium sulfide nonahydrate solution (10 wt%) and stirred to dissolve. Then, 0.03 g of ZIF-8 powder was added. After that, 100 μL of sodium dodecyl sulfate solution was added to the mixed solution, foamed under high-speed rotation (1500 rpm), and then frozen. Then, the mixture was placed in a freeze dryer for processing. After freeze-drying, it was washed with deionized water and then continued to freeze-dry to obtain a hemostatic sponge material.

[0051] Example 4

[0052] (1) Dissolve 0.3 g of zinc nitrate hexahydrate and 0.66 g of 2-methylimidazole in 14.3 mL of methanol. The two solutions were mixed and stirred at room temperature (22°C) for 2 h. The mixture was centrifuged at 10,000 rpm for 10 min, and the powder particles were collected and washed three times with methanol to remove excess zinc nitrate and 2-methylimidazole. The washed powder particles were dried at 70°C for 12 h to obtain ZIF-8 powder.

[0053] (2) First, 0.1 g of wool keratin powder was dissolved in 1 mL of sodium sulfide nonahydrate solution (10 wt%) and stirred to dissolve. Then, 0.05 g of ZIF-8 powder was added. After that, 100 μL of sodium dodecyl sulfate solution was added to the mixed solution, foamed under high-speed rotation (1500 rpm), and then frozen. Then, the mixture was placed in a freeze dryer for processing. After freeze-drying, it was washed with deionized water and then freeze-dried to obtain a hemostatic sponge material.

[0054] Test and Inspection

[0055] The blood absorption ratio test was conducted on the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4. The results are as follows: Figure 3 It is shown that the keratin / zeolite imidazolate skeleton composite hemostatic sponge with shape memory function can absorb blood to concentrate effective coagulation components.

[0056] The shape memory performance test of the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4 was carried out. The results are as follows: Figure 4 、 Figure 5 shown.

[0057] Specific experimental steps: Use a vernier caliper to measure the initial height of the cylindrical sponge and record it as L1, then compress the sponge sample to achieve shape fixation. At this time, measure the height of the fixed sponge and record it as L2. Next, inject 1 mL of water into the surface of the shape-fixed sponge and use a mobile phone camera to record the shape recovery process. The height of the sponge after recovery is set as L3. The shape fixation strain, shape recovery strain, and strain recovery rate are calculated according to the following formulas:

[0058]

[0059] The results showed that Examples 1, 2, 3, and 4 were able to achieve a fixed strain of at least 60%. After immersion in water, the fixed sponges of Examples 1 and 2 were able to recover their original shapes within 1 and 2 seconds, respectively. The recovery rate of the sponges of Examples 1 and 2 was 100%. This indicates that the sponges can quickly recover their original shape upon contact with blood, compressing the bleeding wound and achieving hemostasis.

[0060] The whole blood coagulation index of the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4 was tested. Figure 6 shown.

[0061] Specific experimental steps: Examples 1, 2, 3, and 4 were cut into circular shapes and placed in a culture dish preheated at 37°C for 5 min. 100 μL of blood was then dripped onto the surface of each sponge sample. A 0.2 mol / L CaCl₂ solution (10 μL, 0.2 mol / L) was gently added to the surface of the material to induce coagulation. After all samples were placed in a culture dish and incubated at 37°C for 5 min, 25 mL of deionized water was slowly added from the edge of each culture dish to rinse away uncoagulated red blood cells without disturbing the clot. Uncoagulated red blood cells will hemolyze in the water. Finally, 100 μL of the supernatant was transferred to a 96-well plate and the absorbance was measured at 540 nm using a microplate reader (Varioskan LUX, ThermoFisher) (n = 5 per group). The absorbance value is a key criterion for accurately assessing the amount of unbound blood (higher OD values ​​indicate slower coagulation rates). The absorbance of 100 μL of whole blood in 25 mL of deionized water was used as a blank control. The BCI was calculated using the following formula:

[0062]

[0063] Where Is and Ib are the absorbance values ​​of different sponge sample groups and blank control group, respectively.

[0064] The whole blood clotting time of the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4 was tested. Figure 7 shown.

[0065] Specific experimental steps: Weigh 10 mg of each sponge sample (placed in a 2.5 mL test tube) and incubate at 37°C for 5 minutes. Empty test tubes were used as blank controls. Then, 1 mL of fresh whole rabbit blood was added to each test tube, along with sodium citrate and 20 μL of a 0.2 mol / L CaCl₂ solution. The tubes were inverted every 15 seconds until the blood stopped flowing (inverted to 180°). The time from the addition of the CaCl₂ solution to the completion of clotting was recorded as the blood clotting time (BCT). The experiment was repeated three times for each group.

[0066] The red blood cell adsorption of the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4 was studied. Figure 8 、 Figure 9 shown.

[0067] Specific experimental steps: Before the assay, rabbit whole blood was collected in an anticoagulated tube and centrifuged at 1500 rpm for 10 minutes to obtain a RBC suspension and platelet-rich plasma (PRP). For the RBC adhesion test, sponge samples (10 mg) were preheated at 37°C for 30 minutes and then incubated with RBC solution (250 μL) at 37°C for 30 minutes. Next, the samples were washed five times with phosphate-buffered saline (PBS) to remove RBCs adhered to the samples. The samples were then rinsed in 5 mL of deionized water to lyse the adhered RBCs and release hemoglobin. After 1 hour, 100 μL of the supernatant was removed and placed in a 96-well microplate. The absorbance of the solution was measured at 540 nm using a microplate reader (Varioskan LUX, Thermo Fisher Scientific). A solution consisting of 250 μL of RBC suspension and 5 mL of deionized water was used as a control group. The percentage of adhered RBCs was calculated using the following formula:

[0068]

[0069] Among them I s and I c are the absorbance values ​​of the sponge sample group and the control group, respectively.

[0070] Sponges incubated with RBCs were rinsed with PBS and fixed with 2.5% glutaraldehyde for 4 hours. Prior to scanning, the samples were dehydrated in a series of 50%, 75%, 85%, 95%, and 100% ethanol solutions, with 20-minute intervals. Finally, the samples were vacuum-dried and sputter-coated with platinum. The adhesion of RBCs to the surface and interior of each sample group was observed using SEM.

[0071] The platelet adsorption of the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4 was studied. Figure 10 , Figure 11 shown.

[0072] Specific experimental procedures: For the platelet adhesion assay, a lactate dehydrogenase (LDH) assay was performed to quantify the degree of platelet adhesion to different sponges by measuring the LDH released from lysed platelets. Sponge samples (10 mg) were preheated at 37°C for 30 min in a 24-well plate and then incubated with PRP (100 μL) at 37°C for 30 min. Subsequently, the samples were gently washed five times with phosphate-buffered saline (PBS, pH = 7.4) to remove non-adherent platelets. To lyse adherent platelets, the samples were immersed in 1% Triton X-100 and rinsed at 37°C for 1 hour. The number of platelets adhered to the sponge surface was determined using an LDH detection kit (Yuannuo Tiancheng, Chengdu, China). A solution consisting of 100 μL of PRP was used as a control group, which was not incubated with the sponge. The percentage of adherent platelets was calculated using the following formula:

[0073]

[0074] Among them I s and I c are the absorbance values ​​of the sponge sample group and the control group, respectively.

[0075] Sponges incubated with PRP were rinsed with PBS and fixed with 2.5% glutaraldehyde for 4 hours. Prior to scanning, the samples were dehydrated in a series of 50%, 75%, 85%, 95%, and 100% ethanol solutions, with 20-minute intervals. Finally, the samples were vacuum-dried and sputter-coated with platinum. Platelet adhesion on the surface and interior of each sample group was observed using SEM.

[0076] The antibacterial properties of the keratin / zeolite imidazolate skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4 were studied. Figure 12 , Figure 13 shown.

[0077] Specific experimental steps: The antibacterial activity of sponges was evaluated using Escherichia coli (Gram-negative bacteria) and Staphylococcus aureus (Gram-positive bacteria). Bacterial suspensions co-cultured with PBS were set as the control group. Bacterial colony counts and live / dead staining were used to describe the antibacterial rate and bacterial activity of all samples. The details of the antibacterial experiment were carried out according to previous reports. First, 10 mg of sponge sample was placed in a 2 mL sterile Eppendorf tube. The bacteria were then diluted to 1×*10 6Colony-forming units (CFU / mL) were added to each test tube and incubated at 37°C for 4 h. The bacterial suspension was then serially diluted 10-fold in sterile PBS, and 100 μL of the dilution was plated on a solid nutrient agar plate and incubated overnight at 37°C for 12 h. Finally, the plate was photographed and the number of colonies was counted using an automatic colony counter. For live / dead cell staining, bacteria were stained using a live / dead bacterial viability kit (Invitrogen, USA) and observed by laser confocal scanning microscopy (LCSM, Nikon). All experiments were performed in triplicate, and the bacterial killing rate was calculated according to the following formula:

[0078]

[0079] The hemostasis of rat femoral artery puncture bleeding was studied using the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4. Figure 14 shown.

[0080] Specific experimental procedures: First, the thigh of an anesthetized rat was shaved, and the thigh muscle was incised to expose the femoral artery. A syringe needle was then inserted into the femoral artery, creating a bleeding wound. The test specimen was immediately placed at the bleeding site, and manual pressure was applied with pre-weighed sterile gauze. The specimen was gently lifted, and bleeding was observed until it stopped. The time and volume of bleeding to hemostasis were recorded.

[0081] The hemostasis of rabbit ear artery bleeding by the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1 and 3 was studied. Figure 15 shown.

[0082] The experimental procedure involved shaving the rabbit's ear hair to expose the artery. The artery was then swabbed with iodine and punctured with a syringe to induce bleeding. After bleeding, the wound was covered with a pre-weighed sponge. Next, the specimen was gently lifted and observed for bleeding until it stopped. The time and volume of bleeding to stop were recorded.

[0083] The hemostasis of rat liver penetrating bleeding by the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4 was studied. Figure 16 shown.

[0084] The experimental procedures were as follows: First, the abdominal hair of anesthetized rats was shaved and the rats were secured to an operating table. Next, the liver of each rat was exposed through an abdominal incision, and the surrounding fluid was gently removed with filter paper. A pre-weighed filter paper was placed under the liver, and a bleeding hole was created in the liver using a 6 mm inner diameter perforator. The sponge sample was then immediately placed in the bleeding hole. The time and volume of hemostasis were recorded.

[0085] The hemostasis of the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1 and 3 was studied on the hemostasis of rabbit liver penetrating injury bleeding. Figure 17 shown.

[0086] Specific experimental procedures: The subjects were anesthetized with Sumianxin injection (0.2 mL / kg, intramuscularly) and secured to the operating table. The abdominal cavity was then opened along the midline to expose the liver, and the surrounding serous fluid was carefully removed with gauze. Filter paper was placed beneath the liver, and a circular perforation with a diameter of 10 mm was made. After bleeding, the sponge sample was placed into the wound cavity. Finally, the time and amount of hemostasis were recorded.

[0087] The cytotoxicity of the keratin / zeolite imidazole ester skeleton composite hemostatic sponge with shape memory function in Examples 1, 2, 3, and 4 was studied. Figure 18 shown.

[0088] Specific experimental procedures: To investigate cell viability, a cell counting kit (CCK-8) assay was performed using L929 fibroblasts to assess the cytotoxicity of each sponge sample. Prior to the assay, the sponge samples were irradiated with ultraviolet light for 30 minutes to kill bacteria. 100 μL of the cell suspension (100 μL) was seeded into a 96-well plate and incubated in a 37°C, 5% CO2 incubator for 24 hours. Simultaneously, the sponge samples were immersed in cell culture medium for 24 hours to obtain a sponge extract. After incubation, the medium was aspirated from the wells and replaced with 100 μL of the sponge extract. Subsequently, 10 μL of CCK-8 reagent was added to each well of the 96-well plate and incubated at 37°C for a further 2 hours. The absorbance of each well was measured at 450 nm using a microplate reader (Varioskan LUX, Thermo Fisher Scientific). The absorbance value obtained is proportional to the number of viable cells in the culture. Cells not treated with the sponge extract served as a control. The experiment was repeated three times for each group. Cell survival rate was calculated using the following formula:

[0089]

[0090] Among them A s represents the absorbance value of the sponge group, A c represents the absorbance value of the control group, A b Represents the absorbance value of pure CCK-8 solution.

[0091] Technical personnel should note: Although the present invention has been described according to the above specific implementation methods, the inventive concept of the present invention is not limited to this invention. Any modification using the inventive concept will be included in the scope of protection of this patent.

[0092] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A keratin zeolite imidazole acid framework composite sponge with shape memory function, characterized in that: The composite sponge includes a keratin material and a zeolite imidazolate skeleton, wherein the zeolite imidazolate skeleton is one or more of ZIF-8 and ZIF-67. The composite sponge has a porous structure and is prepared by the following steps: (1) Compound A and 2-methylimidazole are dissolved in methanol respectively, the two solutions are mixed and stirred at room temperature, the mixture is centrifuged, powder particles are collected and washed with methanol to remove excess compound A and 2-methylimidazole, and the washed powder particles are dried at 70° C. for 12 h to obtain product A, wherein compound A is one or more of zinc nitrate hexahydrate and cobalt nitrate hexahydrate, and product A is a zeolitic imidazole ester framework material containing one or more of ZIF-8 and ZIF-67; (2) Keratin material powder is dissolved in sodium sulfide nonahydrate solution and stirred to dissolve, and then product A is added in different mass ratios, and sodium dodecyl sulfate solution is added to the mixed solution. After foaming under high-speed rotation, it is frozen and freeze-dried. After freeze-drying, it is washed with deionized water and then freeze-dried to obtain the composite sponge material.

2. The keratin zeolite imidazole acid framework composite sponge with shape memory function according to claim 1, characterized in that: The keratin material is one or more of human hair keratin, feather keratin and wool keratin.

3. The keratin zeolite imidazole acid framework composite sponge with shape memory function according to claim 1, characterized in that: The keratin material powder is dissolved in the sodium sulfide nonahydrate solution to a concentration of 10 wt%.

4. The keratin zeolite imidazole acid framework composite sponge with shape memory function according to claim 1, characterized in that: The mass percentage of the product A in the keratin material powder is 10-50%.

5. The keratin zeolite imidazole acid framework composite sponge with shape memory function according to claim 1, characterized in that: The mass percentage of the sodium lauryl sulfate in the keratin material powder is 5%.

6. Use of the keratin zeolite imidazole acid framework composite sponge with shape memory function according to claim 1 in preparing hemostatic materials.

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