Hydrogel based on photo-crosslinking protein and clay material as well as preparation method and application of hydrogel

Abstract

The invention relates to the technical field of medical isolation materials, in particular to hydrogel based on photo-crosslinked protein and a clay material as well as a preparation method and application of the hydrogel. The hydrogel is prepared from the following raw materials in percentage by weight: 5 to 25 percent of photo-crosslinking protein, 0.5 to 20 percent of clay material, 0.1 to 1 percent of initiator and the balance of solvent, the crosslinking thickness of the hydrogel is greater than or equal to 8mm. By optimizing the selection and concentration of the photo-crosslinking protein, the clay material and the initiator in the hydrogel and matching with specific crosslinking conditions, the obtained hydrogel has the advantages of high mechanical strength, adjustable thickness, high gelation speed, low immunogenicity and adjustable biodegradability, and is particularly suitable for tissue isolation and protection during tumor radiotherapy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical isolation materials, in particular to a hydrogel based on photo-cross-linking protein and clay material, and a preparation method and application thereof. BACKGROUND

[0002] With the increasing number of people diagnosed with tumors, radiotherapy as an effective medical means is widely used. However, effective radiotherapy often requires high-dose radiation intensity, which seriously affects the normal tissues adjacent to the tumor site, resulting in problems such as the destruction of the structure of normal cells, DNA damage, additional inflammatory reactions, and the weakening of immune function during treatment. The hydrogel spacer increases the physical distance between the tumor and the adjacent organs, thereby reducing the irradiation dose of the adjacent organs, providing a feasible idea for radiotherapy protection. Existing hydrogel spacers include cross-linked sodium hyaluronate hydrogel or polyethylene glycol in situ curing hydrogel. However, the existing radiotherapy protection hydrogel is only suitable for implantation in a closed space, and the approved indication is radiotherapy protection for prostate cancer. However, for open spaces (such as tumor isolation protection in the abdominal cavity), the hydrogel is prone to flow and displacement after injection, making it difficult to establish an effective and stable isolation thickness, affecting the isolation protection effect, and failing to meet the use requirements of radiotherapy protection materials. At the same time, the existing hydrogel can only be cross-linked in a small scale, so its application range is limited to the skin surface and the internal tissues, and it cannot be applied between organs to fully play a blocking role.

[0003] Chinese patent application CN120267879A discloses a hydrogel adhesive, which is prepared by modifying a clay material and compounding with modified gelatin, solving the problems of insufficient adhesion and mechanical properties in a humid environment. However, the viscosity of the adhesive is small, and the cross-linking thickness is low, which cannot be used as a barrier material.

[0004] Under such circumstances, there is an urgent need to provide a hydrogel material that can be injected and implanted, has strong plasticity, and is suitable for use in open spaces in the body, to meet the use requirements of radiotherapy protection materials. SUMMARY

[0005] To solve the above technical problems, the present application provides a hydrogel material with a wide application range, which can be injected and implanted, has strong plasticity, stably stays without flowing after implantation, and has sufficient thickness and hardness, meeting the application requirements of biomedical materials and being suitable for use in open spaces in the body. By optimizing the selection and concentration of photo-cross-linking protein, clay material, and initiator in the hydrogel, and combining with specific cross-linking conditions, the obtained hydrogel has the advantages of high mechanical strength, adjustable thickness, fast gelation speed, low immunogenicity, and adjustable biodegradability, and is especially suitable for tissue isolation and protection during tumor radiotherapy.

[0006] The first aspect of the present application provides a hydrogel based on photo-crosslinking protein and clay material, the raw materials for preparing the hydrogel include, in terms of weight percentage, 5-25% of photo-crosslinking protein, 0.5-20% of clay material, 0.1-10‰ of initiator, and the balance of solvent.

[0007] Optionally, the crosslinking thickness of the hydrogel is ≥8mm.

[0008] Optionally, the photo-crosslinking protein includes an acrylic compound modified protein matrix.

[0009] Optionally, the acrylic compound includes a combination of one or more of methacrylic acid, methacrylic anhydride, glycidyl methacrylate, tripropylene glycol diacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, polyethylene glycol diacrylate, isobornyl acrylate, and 1,6-hexanediol diacrylate.

[0010] Further optionally, the acrylic compound includes methacrylic acid, methacrylic anhydride, or glycidyl methacrylate.

[0011] Optionally, the protein matrix includes a combination of one or more of gelatin, silk fibroin, collagen, keratin, and extracellular matrix.

[0012] Further optionally, the protein matrix is gelatin, the acrylic compound is methacrylic anhydride, and the photo-crosslinking protein is methacrylated gelatin (GelMA).

[0013] Natural proteins generally have good biocompatibility and biodegradability, and can be implanted into the body as implants to reduce adverse reactions to the body. However, natural proteins have poor water solubility and form solutions with low viscosity; and the crosslinking methods available for natural proteins are limited, which not only results in relatively weak mechanical properties of the hydrogels formed therefrom, but also makes it difficult to precisely control the degradation rate of the hydrogels. Existing natural protein materials are mainly used for tissue regeneration, and have not been applied to radiotherapy protection materials. The present application accidentally found that using an acrylic compound modified protein matrix as a photo-crosslinking protein can construct a stable crosslinking system with a specific clay material, and obtain a large-scale crosslinked hydrogel, which meets the use requirements of radiotherapy protection materials.

[0014] Optionally, the clay material is a silicate mineral.

[0015] Optionally, the clay material includes a combination of one or more of montmorillonite, attapulgite, hectorite, and lithium magnesium silicate.

[0016] Optionally, the specific surface area of the clay material is 200-500m 2 / g.

[0017] Further optionally, the clay material is magnesium lithium silicate.

[0018] Still further optionally, the specific surface area of the magnesium lithium silicate is 300-400 m 2 / g.

[0019] As a kind of inorganic material with excellent biocompatibility, clay material can be applied to bone tissue repair and other implantable clinical scenarios. At the same time, clay material has good dispersion performance in solution, which can improve the viscosity and stability of coatings and other products. However, the existing clay material is usually used as a physical filler and a drug delivery carrier, and there is currently no technology to apply it to a cross-linked and solidified hydrogel system. The present application innovatively uses clay material as a key component to prepare in-situ solidified hydrogel to meet the use requirements of radiotherapy protection materials. The present application preferably uses silicate minerals as clay material, and further preferably uses magnesium lithium silicate with a layered structure and a large specific surface area, which can solve the technical defects of the existing hydrogel that can only be cross-linked in small scale and cannot be used as a barrier material. The obtained hydrogel has a cross-linked thickness of ≥8 mm, and the obtained hydrogel can be used to play a barrier role between organs and meet the use requirements of radiotherapy protection materials.

[0020] Optionally, the amount of the initiator added is 0.1-10 ‰; further optionally, the amount of the initiator added is 1-8 ‰.

[0021] Optionally, the initiator has biocompatibility and includes at least one of lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (photoinitiator 2959), photoinitiator 184, photoinitiator 1173, photoinitiator TPO, photoinitiator 651, photoinitiator 819, and eosin Y; the initiator can also be a metal ion / hydrogen peroxide complex system.

[0022] Further optionally, the initiator is LAP.

[0023] In some embodiments, the solvent of the present application can be listed as water.

[0024] Optionally, the degradation time of the hydrogel is 1-40 days.

[0025] The second aspect of the present application provides a preparation method of the hydrogel as described above, and the preparation steps of the hydrogel include: mixing photo-crosslinking protein, clay material, initiator and solvent according to the formula amount, photo-radiation cross-linking to obtain hydrogel finished product.

[0026] Optionally, the preparation steps of the hydrogel specifically include:

[0027] S1. preparing a photo-crosslinking protein precursor solution containing an initiator;

[0028] S2. preparing a clay precursor solution containing an initiator;

[0029] S3. mixing the photo-crosslinking protein precursor solution and the clay precursor solution uniformly, and performing photo-radiation crosslinking using ultraviolet light or visible light to obtain a hydrogel product.

[0030] In some embodiments, the preparation step of the photo-crosslinking protein comprises: dissolving a protein matrix in a buffer, adding an acrylic compound, and mixing uniformly; stirring at 30-50℃ and 200-500rpm for 1-5h to obtain a reaction product; performing a dialysis operation on the reaction product, and freezing overnight; and obtaining a photo-crosslinking protein product after freeze-drying.

[0031] The buffer can include a PBS (phosphate) buffer.

[0032] Optionally, the molecular weight cut-off of the dialysis operation is 2000-5000Da; and further optionally 3500Da.

[0033] Optionally, the photo-radiation crosslinking condition is: a photo-radiation wavelength of 300-680nm, a photo-radiation energy of 50-200mW / cm 2 , and a crosslinking time of 0.5-5min.

[0034] Further optionally, the photo-radiation crosslinking condition is: a photo-radiation wavelength of 350-480nm, a photo-radiation energy of 80-150mW / cm 2 , and a crosslinking time of 1-4min.

[0035] The third aspect of the present application provides an application of the hydrogel as described above, which is applied to radiotherapy protection materials, surgical sealants or tissue engineering scaffold materials.

[0036] In some embodiments, the hydrogel of the present application is preferably in the form of a gasket, and is used as a barrier material.

[0037] Advantages:

[0038] The present application provides a hydrogel based on photo-crosslinking protein and clay material, as well as a preparation method and application thereof, which has the following advantages:

[0039] (1) The present application uses photo-crosslinking protein and clay material to prepare a hydrogel, and the obtained hydrogel is in a semi-solid gel form before photocuring, has injectability, high viscosity and certain plasticity, can be retained at the target site after injection, and can be cured in situ in the body, meeting the use requirements of radiotherapy protection materials.

[0040] (2) The preferred photocrosslinking protein of the present application is GelMA, the clay material is magnesium lithium silicate, and the obtained hydrogel has the performance of photocrosslinking curing in a large thickness interval range, can be cured at the target site to form a hydrogel pad with a certain hardness, and meets the use requirements of different organs or tissues for the hardness and thickness of the hydrogel during radiotherapy isolation.

[0041] (3) The hydrogel of the present application significantly improves the mechanical properties of natural protein hydrogel, and has a high degree of matching with the mechanical properties of tissues / organs. The obtained hydrogel can still maintain the supporting strength at a compression strain of 50% or more, has strong adaptability, and can fully play a role in the complex biological environment of the implanted body.

[0042] (4) The hydrogel prepared by the present application has excellent anti-swelling property, and can maintain the volume of the hydrogel basically unchanged in the actual implanted clinical application scene, effectively avoids additional compression to the tissue, and fully plays a physical blocking role.

[0043] (5) The raw materials used in the present application are biocompatible, safe and degradable natural materials. The mechanical properties, swelling properties and degradation period of the hydrogel can be adjusted according to the use requirements. The hydrogel can be degraded within 1-40 days, avoiding the immune rejection reaction caused by long-term retention of the material, and has high immunogenicity.

[0044] (6) The preparation process of the hydrogel of the present application is simple, and the hydrogel can be fully crosslinked in 1-5 min, and has strong operability; it is suitable for wide promotion in the field of biomedical materials, and has wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 . Fourier infrared spectrum of the hydrogel of Preparation Example 1 (the blue line in the figure corresponds to the hydrogel prepared in Example 1, the black line corresponds to methyl acrylated gelatin, and the red line corresponds to clay);

[0046] Figure 2 . Temperature-sensitive performance test photos of the clay precursor solution and the composite material precursor solution;

[0047] Figure 3 . Hydrogel formation result graph of Example 1;

[0048] Figure 4 . Mechanical test results of the hydrogel of Example 1;

[0049] Figure 5 . Stress-strain relationship graph of the hydrogel of Example 1;

[0050] Figure 6 . Hydrogel formation result graph of Example 2;

[0051] Figure 7. Mechanical test results of the hydrogel of Example 2;

[0052] Figure 8 . Stress-strain relationship graph of the hydrogel of Example 2;

[0053] Figure 9 . Gelation results graph of the hydrogel of Example 3;

[0054] Figure 10 . Mechanical test results of the hydrogel of Example 3;

[0055] Figure 11 . Stress-strain relationship graph of the hydrogel of Example 3;

[0056] Figure 12 . Gelation results graph of the hydrogel of Example 4;

[0057] Figure 13 . Mechanical test results of the hydrogel of Example 4;

[0058] Figure 14 . Stress-strain relationship graph of the hydrogel of Example 4;

[0059] Figure 15 . Swelling rate test results of the hydrogel of Example;

[0060] Figure 16 . Degradation test results of the hydrogel of Example;

[0061] Figure 17 . Gelation results graph of the hydrogel of Comparative Example;

[0062] Figure 18 . Mechanical test results of the hydrogel of Comparative Example. DETAILED DESCRIPTION

[0063] The present application will be further described in conjunction with specific examples to enable those skilled in the art to better understand and implement the technical solutions of the present application, but the present application is not limited to the following examples, and any improvement and modification based on the concept of the present application falls within the protection scope of the present application.

[0064] Part of the raw material information of the embodiments of the present application is as follows.

[0065] The gelatin is pig gelatin with a gel strength of ~100g Bloom, and is sourced from Shanghai Aladdin Biochem Technology Co., Ltd.

[0066] The clay material is lithium magnesium silicate, and the specific surface area of the lithium magnesium silicate is 370m 2 / g, sourced from BYK Chemical, and the model is Laponite XLG-XR.

[0067] Note: If no special instructions, the solvent of the solution involved in the present application is water; the concentration involved is mass concentration; room temperature is 25℃; and the raw materials used are commercially available.

[0068] Preparation Example 1

[0069] Dissolve 10 g of gelatin in 100 mL of PBS buffer, add 10 mL of methacrylic anhydride, mix thoroughly, and place the mixture in a 40℃, 300 rpm condition for 3 h to perform the methacrylation reaction; after the reaction is completed, add 200 mL of PBS buffer to terminate the reaction, obtain the reaction product; use a dialysis bag with a molecular weight cut-off of 3500 Da to dialyze the reaction product in deionized water for 3 days, then freeze overnight at -80℃, and freeze dry for 72 h to obtain the photocrosslinked protein, which is methacrylated gelatin (GelMA).

[0070] The following examples all use the photocrosslinked protein prepared in this preparation example 1 to prepare hydrogels.

[0071] Preparation Example 2

[0072] Mix 0.05 g, 0.03 g, and 0.01 g of clay material with 1 mL of water respectively to prepare clay precursor solutions with concentrations of 5%, 3%, and 1% respectively, denoted as C1, C2, and C3.

[0073] The temperature-sensitive performance of the clay precursor solution is shown in Figure 2 .

[0074] Preparation Example 3

[0075] Mix 0.05 g, 0.03 g, and 0.01 g of clay material with 1 mL of water respectively, and add 0.1 g of GelMA to each solution to prepare composite material (GelMA-clay) precursor solutions with clay concentrations of 5%, 3%, and 1% respectively, denoted as GC1, GC2, and GC3.

[0076] The temperature-sensitive performance of the composite material precursor solution is shown in Figure 2 .

[0077] As Figure 2 shown in the following figure, the temperature-sensitive performance of the precursor solution of different concentrations was tested by observing the gelation state of the hydrogel to characterize the temperature-sensitive performance of the material. Figure 2 As shown in the figure, the clay precursor solution with the preferred concentration of the present application all presents a hydrogel state at room temperature, while the gelation states of the composite material (GelMA-clay) with different concentrations at room temperature are different, GC1 presents a complete hydrogel state, and GC2 and GC3 present a partial gelation state. The above results show that the clay can increase the concentration of the hydrogel prepolymer, which is helpful for pre-shaping after in vivo injection and improves the plasticity of the hydrogel.

[0078] Example 1

[0079] Example 1 provides a hydrogel based on photo-crosslinking protein and clay material, and the preparation raw materials of the hydrogel include: photo-crosslinking protein, clay material, initiator (LAP) and water.

[0080] The preparation steps of the hydrogel include:

[0081] S1. 96 mg of LAP was weighed and dissolved in 12 mL of deionized water, and stirred at 300 rpm in the dark for 15 min to prepare a mother liquor;

[0082] S2. 2 mL of the mother liquor was taken and labeled as L5; 1 mL of the mother liquor was mixed with 1 mL of deionized water and labeled as L4; 0.5 mL of the mother liquor was mixed with 1.5 mL of deionized water and labeled as L3; 0.25 mL of the mother liquor was mixed with 1.75 mL of deionized water and labeled as L2; 0.125 mL of the mother liquor was mixed with 1.875 mL of deionized water and labeled as L1;

[0083] S3. 1 mL of the above solution was taken respectively, 0.2 g of GelMA and 20 mg of clay were added to prepare a clay precursor solution and a photo-crosslinking protein precursor solution, and the clay precursor solution and the photo-crosslinking protein precursor solution were mixed and dissolved at 40°C and 300 rpm for 30 min to obtain hydrogel samples with different initiator concentrations, which were labeled as LAP5, LAP4, LAP3, LAP2 and LAP1 respectively;

[0084] S4. The hydrogel was irradiated with ultraviolet light to form a gel, and the irradiation conditions were 100 mw / cm 2 , 2 min.

[0085] The concentrations of each raw material in the hydrogel of Example 1 are shown in Table 1.

[0086] As Figure 3 shown in the physical map of the hydrogel of Example 1. From Figure 3 it can be seen that the hydrogel of the application uses a photo-initiator (LAP) precursor solution with a preferred concentration range, and after crosslinking, hydrogels with thicknesses of 8 mm and 12 mm can be formed; the obtained hydrogel is transparent in color, uniform in texture, and the edge is clear and complete. The above results show that when the preferred photo-initiator is LAP and the concentration is in the range of 1 ‰-8 ‰, the forming ability of the hydrogel can be improved, the obtained hydrogel can be crosslinked, and has certain mechanical strength characteristics.

[0087] As Figure 4 , Figure 5 shown in the mechanical test results of the hydrogel of Example 1. From Figure 4As can be seen, the compression strength of the hydrogel prepared after the preferred concentration of the light initiator (LAP) of the present application participates in the photocrosslinking ranges from 93.95 kPa to 233.27 kPa, the strain ranges from 42.3% to 81%, and the Young's modulus ranges from 0.0125 MPa to 0.1116 MPa. The data show that the hydrogel prepared with 0.5‰ of the light initiator has the largest Young's modulus, and the hydrogel prepared under the condition of 2‰ of the light initiator has the largest compression strength and strain. These test results show that the hydrogel prepared by the present application has good compression resistance and can withstand a strain of more than 40%, and the mechanical properties of the hydrogel prepared with 2‰ of the light initiator are the most advantageous.

[0088] Example 2

[0089] Example 2 provides a hydrogel based on light cross-linking protein and clay material, and the preparation raw materials of the hydrogel include: light cross-linking protein, clay material, initiator (LAP) and water.

[0090] The preparation steps of the hydrogel include:

[0091] S1. 12 mg of LAP was weighed and dissolved in 12 mL of deionized water, and stirred at 300 rpm in the dark for 15 min to prepare a mother liquor;

[0092] S2. 100 mg of clay was taken in 5 mL of the mother liquor, wrapped in aluminum foil, and stirred at 600 rpm for 2 h to obtain a clay precursor solution;

[0093] S3. 0.1 g, 0.2 g, 0.3 g and 0.4 g of GelMA were respectively weighed in 1 mL of the mother liquor, wrapped in aluminum foil, and dissolved at 40°C and 300 rpm for 30 min to obtain light cross-linking protein precursor solutions with different concentrations;

[0094] S4. The light cross-linking protein precursor solutions (1 mL) with different concentrations were respectively mixed with 1 mL of the clay precursor solution, and dissolved at 300 rpm for 10 min to obtain hydrogel samples with different concentrations of GelMA, which were respectively labeled as G1, G2, G3 and G4;

[0095] S5. The hydrogel was irradiated with ultraviolet light to form a gel, and the irradiation conditions were 100 mw / cm 2 , 2 min.

[0096] The concentrations of the raw materials in the hydrogel of Example 2 are shown in Table 1.

[0097] As Figure 6 shown in the figure is the actual hydrogel of Example 2. Figure 6It is shown that the hydrogels with thickness of 8mm and 12mm can be formed after cross-linking of the light cross-linking protein with different concentrations in embodiment 2 of the present application. Among them, the hydrogels in groups G2, G3 and G4 are transparent in color, uniform in texture, clear and complete in edge, the cross-linking of the hydrogels is good, and the hydrogels have certain mechanical strength characteristics; while the hydrogels in group G1 cannot be placed vertically, the edge is not clear, the plasticity of the hydrogels is poor, and no subsequent test is performed.

[0098] As shown in Figure 7 , Figure 8 the mechanical test results of the hydrogels in embodiment 2 are shown. As can be seen from Figure 7 , with the increase of the concentration of the GelMA precursor solution, the compression strength of the hydrogels after cross-linking shows an increasing trend, and the strain shows a decreasing trend as a whole. The test results show that the hydrogels prepared in embodiment 2 have good compression resistance and can withstand a strain of more than 50%. The preferred GelMA concentration can significantly improve the compression strength and Young's modulus of the hydrogels and reduce the strain performance of the hydrogels. At the same time, the concentration of GelMA can be flexibly adjusted according to the mechanical environment of the tissue site, and further adapted to the tissue site or other application scene materials.

[0099] Embodiment 3

[0100] Embodiment 3 provides a hydrogel based on light cross-linking protein and clay material, and the preparation raw materials of the hydrogel include: light cross-linking protein, clay material, initiator (LAP) and water.

[0101] The preparation steps of the hydrogel include:

[0102] S1. 12mg of LAP was weighed and dissolved in 12mL of deionized water, and stirred at 300rpm in the dark for 15min to prepare a mother liquor;

[0103] S2. 0g, 20mg, 60mg, 100mg and 140mg of clay were respectively mixed with 1mL of the mother liquor, wrapped with aluminum foil and stirred at 600rpm for 2h to obtain clay precursor solutions with different concentrations;

[0104] S3. 1.2g of GelMA was weighed in 6mL of the mother liquor, wrapped with aluminum foil, and dissolved at 40℃ and 300rpm for 30min to obtain a light cross-linking protein precursor solution;

[0105] S4. 1mL of the light cross-linking protein precursor solution was mixed with 1mL of the clay precursor solution with different concentrations, and dissolved at 300rpm for 10min, respectively labeled as C1, C2, C3, C4 and C5;

[0106] S5. The hydrogels were irradiated with ultraviolet light to form a gel, and the irradiation conditions were 100mw / cm2 2min.

[0107] The concentrations of the raw materials in the hydrogel of Example 3 are shown in Table 1.

[0108] As shown in Figure 9 , it is a physical picture of the hydrogel of Example 3. Figure 9 It is shown that the nanoclay precursor solution of the preferred concentration of the present application can form hydrogels with a thickness of 8 mm and 12 mm after cross-linking. The obtained hydrogels are transparent in color, uniform in texture, clear and complete in edge, and have good cross-linking conditions and certain mechanical strength characteristics, and good plasticity.

[0109] As shown in Figure 10 , Figure 11 , it is the mechanical test result of the hydrogel of Example 3. Figure 10 It is shown that with the increase of the concentration of the clay solution, the compression strength of the hydrogel after cross-linking shows a trend of first increasing and then decreasing, and the strain shows a trend of decreasing. The above results show that the prepared hydrogel has good compression resistance and can withstand a strain of more than 60%. The test results verify that the preferred clay of the present application can improve the compression strength and Young's modulus of the hydrogel and reduce the strain performance of the hydrogel. The present application can flexibly adjust the concentration of the clay according to the mechanical environment of the tissue site, and further adapt to the tissue site or other application scene materials.

[0110] Example 4

[0111] Example 4 provides a hydrogel based on a photo-cross-linking protein and a clay material, and the preparation raw materials of the hydrogel include: a photo-cross-linking protein, a clay material, an initiator (LAP) and water.

[0112] The preparation steps of the hydrogel include:

[0113] S1. 10 mg of LAP was weighed and dissolved in 10 mL of deionized water, and stirred at 300 rpm in the dark for 15 min to prepare a mother liquor;

[0114] S2. 100 mg of clay was taken in 5 mL of the mother liquor, wrapped in aluminum foil, and stirred at 600 rpm for 2 h to obtain a clay precursor solution;

[0115] S3. 1 g of GelMA was weighed and dissolved in 5 mL of the mother liquor, wrapped in aluminum foil, and dissolved at 40℃ and 300 rpm for 30 min to obtain a photo-cross-linking protein precursor solution;

[0116] S4. 1 mL of the photo-cross-linking protein precursor solution was mixed with 1 mL of the clay precursor solution, and dissolved at 300 rpm for 10 min. Three samples were set in parallel and labeled as T1, T2 and T4, respectively;

[0117] S5. UV irradiation was performed on T1, T2 and T4 hydrogels respectively to form gel, and the light radiation energy was 100 mw / cm 2 , and the crosslinking time was 1 min, 2 min and 4 min respectively.

[0118] The concentration of each raw material in the hydrogel of Example 4 is shown in Table 1.

[0119] As shown in Figure 12 , it is the actual picture of the hydrogel of Example 4. Figure 12 It is shown that the hydrogel with a thickness of 8 mm and 12 mm can be formed when the crosslinking time is 1-4 min according to the present application; the hydrogel is transparent in color, uniform in texture, clear and complete in edge, and has good crosslinking condition and certain mechanical strength characteristics, and has good plasticity.

[0120] As shown in Figure 13 , Figure 14 , it is the mechanical test result of the hydrogel of Example 4. Figure 13 It is shown that with the increase of the crosslinking time, the compression strength of the hydrogel after crosslinking presents a change trend of first increasing and then remaining unchanged, and the strain presents a trend of first increasing and then decreasing. The test result verifies that the hydrogel of the present application can be crosslinked quickly, and the obtained hydrogel has good compression resistance and can withstand a strain of more than 60%. The data shows that the specific hydrogel system of the present application can be fully crosslinked only in 2 min and has good mechanical properties, so the most preferred crosslinking time is 2 min.

[0121] Table 1

[0122]

[0123] Comparative Examples 1-5

[0124] Comparative Examples 1-5 provide a hydrogel containing clay material, and the preparation raw materials of the hydrogel include: gelatin, clay material and water; the formula of each comparative hydrogel is shown in Table 2.

[0125] Table 2

[0126] Comparative Example Sample Number Gelatin Concentration Clay Concentration Comparative Example 1 Gelatin / Clay 1 10％ 1％ Comparative Example 2 Gelatin / Clay 2 10％ 3％ Comparative Example 3 Gelatin / Clay 3 10％ 5％ Comparative Example 4 Gelatin / Clay 4 5％ 1％ Comparative Example 5 Gelatin / Clay 5 15％ 1％

[0127] The preparation steps of the hydrogel include: mixing the gelatin, clay and water according to the formula amount, stirring uniformly, and standing to form gel.

[0128] The gelation results of each comparative example are shown in Figure 17 , and it can be seen from Figure 17 that Comparative Examples 1, 2, 3 and 5 can form gel, and the crosslinking strength of Comparative Example 4 is not enough to form gel.

[0129] The mechanical property test was performed on the comparative examples 1, 2, 3 and 5, and the test results are shown in Table 1. Figure 18 As can be seen from Table 1, the strain of the gelatin / clay hydrogel is 0.3% to 43.8%, and the stress is 6411 to 78085 Pa. Although the gelatin and clay can be compounded to form a hydrogel, the stress of the hydrogel product is significantly lower than that of the hydrogel prepared in the examples, and cannot meet the use requirements of the interventional barrier material. Figure 18

[0130] Performance test

[0131] 1, Swelling rate

[0132] The swelling performance of part of the hydrogel samples (LAP1, LAP2, G1, G2, Clay1, Clay15, T1 and T2) was further tested, and the measured swelling rate results are shown in Table 2. Figure 15 .

[0133] The test method of the swelling rate is that each hydrogel sample is soaked in water, and the mass change of the hydrogel is recorded after swelling at 60 DEG C for 24 hours, and the swelling rate is calculated; the swelling rate=(the mass of the hydrogel after soaking-the mass of the hydrogel before soaking) / the mass of the hydrogel before soaking.

[0134] Figure 15 It is shown that the concentration of the photocrosslinking protein, the clay and the photoinitiator in the hydrogel and the crosslinking time all have certain influence on the swelling performance of the hydrogel, and the swelling rate fluctuates with the change of the reaction conditions, but remains around 1.0. The test results show that the hydrogel prepared in the application has excellent anti-swelling property, and can maintain the volume of the hydrogel basically unchanged in the actual implantable clinical application scene, effectively avoids additional compression to the tissue, and fully plays the physical barrier role.

[0135] It should be noted that the formula of the hydrogel samples of LAP2, G2, Clay2 and T2 is the same, and the fluctuation of the swelling rate test results is caused by the test deviation of different batches of experiments, and the test results do not show significant difference, and the test data of the swelling rate is effective.

[0136] 2, Degradation performance

[0137] The degradation performance of part of the hydrogel samples (LAP1, LAP2, G1, G2, Clay1, Clay15, T1 and T2) was further tested, the residual mass of each hydrogel sample soaked in the PBS buffer was determined, and the ratio of the residual mass to the initial hydrogel mass was calculated, and the measured degradation results are shown in Table 3. Figure 16 .

[0138] As Figure 16 ​As shown, the degradation rates of the hydrogels are different. The results show that when the hydrogels are soaked in PBS for degradation, CT1, CT2, G1, LAP1 and LAP2 all show obvious degradation behavior, and the complete degradation period is about 21-80 days; G2 does not show degradation behavior in the 70-day degradation period, and Clay1 and Clay2 show mass loss of 15% and 22% respectively in the early stage, and then the residual mass ratio is basically stable, showing a low degree of increase. The above results show that the degradation range of the hydrogel of the application is wide, and the degradation period can be coordinated according to the actual implantation clinical application scene demand, which can fully play the physical barrier role, and can also avoid the long-term existence of the material to generate additional pressure on the tissue, and can well meet the use demand of the barrier material.

Claims

1. A hydrogel based on a photo-cross-linking protein and a clay material, characterized in that, The raw materials for preparing the hydrogel include, in percentage by weight: photo-crosslinking protein 5-25%, clay material 0.5-20%, initiator 0.1-10‰, and solvent to make up the balance; The crosslinking thickness of the hydrogel is ≥8 mm.

2. The hydrogel based on a photocrosslinking protein and a clay material according to claim 1, characterized in that, The clay material includes a combination of one or more of montmorillonite, attapulgite, hectorite, and lithium magnesium silicate.

3. The hydrogel based on a photocrosslinking protein and a clay material according to claim 2, characterized in that, The specific surface area of the clay material is 200-500 m 2 / g.

4. The hydrogel based on a photocrosslinking protein and a clay material according to claim 2, characterized in that, The clay material is a magnesium lithium silicate having a specific surface area of 300-400 m 2 / g.

5. The hydrogel based on a photocrosslinking protein and a clay material according to claim 1, characterized in that, The photo-crosslinking protein includes an acrylic compound modified protein matrix. Preferably, the photo-crosslinking protein is methacrylated gelatin.

6. The hydrogel based on a photocrosslinking protein and a clay material according to claim 1, characterized in that, The initiator includes at least one of lithium phenyl-2,4,6-trimethylbenzoylphosphinate, photoinitiator 2959, photoinitiator 184, photoinitiator 1173, photoinitiator TPO, photoinitiator 651, photoinitiator 819, and eosin Y.

7. A method of preparing a hydrogel according to any one of claims 1 to 6, characterized in that, The preparation steps of the hydrogel include mixing the photo-crosslinking protein, the clay material, the initiator, and the solvent according to the formula amount, photo-radiation crosslinking, and obtaining the hydrogel product.

8. The method of claim 7, wherein the hydrogel is prepared by, The preparation steps of the hydrogel specifically include: S1. preparing a photo-crosslinking protein precursor solution containing an initiator; S2. preparing a clay precursor solution containing an initiator; S3. uniformly mixing the photo-crosslinking protein precursor solution and the clay precursor solution, and performing photo-radiation crosslinking using ultraviolet light or visible light to obtain the hydrogel product.

9. The method of claim 8, wherein the hydrogel is prepared by, The conditions for the light radiation crosslinking are: light radiation wavelength is 300-680nm, light radiation energy is 50-200mW / cm 2 , and crosslinking time is 0.5-5min.

10. Use of a hydrogel according to any one of claims 1 to 6, characterized in that, The hydrogel is applied to radiotherapy protection materials, surgical sealants, or tissue engineering scaffold materials.

Images