A method for preparing a dual-network hydrogel coating and applications thereof

Abstract

The application discloses a preparation method of a double-network hydrogel coating and relates to the technical field of biomedical materials.The preparation method comprises the following steps: after the surface of a silica gel base material is modified, the silica gel base material is first immersed in a SBMA prepolymer liquid for a certain period of time, and then is heated in a water bath at 60-65 DEG C for a certain period of time; then the silica gel base material is taken out and immersed in a DST prepolymer liquid for a certain period of time; finally, the soaked silica gel base material is irradiated under ultraviolet light for a certain period of time to obtain the double-network hydrogel coating.The double-network hydrogel coating prepared by the method has a relatively stable swelling rate, and when the double-network hydrogel coating is applied as a coating on the inner surface of a silica gel suction disc, the double-network hydrogel coating can slightly swell to fill the tiny texture gullies existing in internal organs or skin, increase the air-tightness of adsorption, and effectively improve the adsorption effect of the silica gel suction disc on the internal organs or skin.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical materials, in particular to a preparation method of a double-network hydrogel coating and application thereof. Background Art

[0002] Hydrogels, due to their excellent hydrophilicity, biocompatibility, and ability to maintain their three-dimensional structure, possess unique advantages and enormous potential for development in the field of biomedical materials. Their excellent biocompatibility has also led to their widespread application in tissue engineering, such as in artificial skin, artificial blood vessels, artificial corneas, contact lenses, artificial joints, various artificial organs, and as sustained-release drug carriers.

[0003] The applicant disclosed in patent number CN 211460332 U a double-sided suction cup for liver retraction. This cup is used to absorb and retract the liver and other organs during laparoscopic upper abdominal surgery to prevent obstruction of the surgical field, resulting in poor surgical field exposure and a narrow operating space. However, because the surface of internal organs and skin is not smooth and dense, but rather contains fine grooves, conventional silicone suction cups can only maintain negative pressure for a short time due to slow air leakage in these grooves, resulting in unsatisfactory suction results. Summary of the Invention

[0004] The present invention aims to at least partially overcome the aforementioned and / or other potential problems in the prior art by providing a method for preparing a double-network hydrogel coating and its application. The double-network hydrogel coating exhibits a stable swelling rate and stability. When applied as a coating on the inner surface of a silicone suction cup, it can effectively enhance the suction effect of the silicone suction cup on organs or skin.

[0005] The technical solution of the present invention is as follows: A method for preparing a double-network hydrogel coating comprises the following steps:

[0006] 1) Add SBMA monomer to deionized water, stir and dissolve, then add crosslinking agent and stir to make it react and crosslink, and finally add thermal initiator and stir to obtain SBMA prepolymer solution;

[0007] 2) Dissolve acrylic acid, gelatin, AAc-NHS ester, GelMa and photoinitiator LAP in deionized water, and deoxygenate after complete dissolution to obtain DST prepolymer solution;

[0008] 3) After surface modification, the silica gel substrate is first immersed in the SBMA prepolymer solution for a predetermined time, and then heated in a water bath at 60-65° C. for a predetermined time; then, the silica gel substrate is removed and immersed in the DST prepolymer solution for a predetermined time; finally, the soaked silica gel substrate is removed and irradiated under ultraviolet light for a predetermined time to prepare a PSBMA-DST double network hydrogel coating.

[0009] The SBMA monomer is [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfonic acid propyl)ammonium hydroxide.

[0010] Preferably, the cross-linking agent is N,N'-methylenebisacrylamide.

[0011] Preferably, the thermal initiator is ammonium persulfate.

[0012] The photoinitiator LAP is phenyl-2,4,6-trimethylbenzoyl lithium phosphite.

[0013] The AAc-NHS ester is N-hydroxysuccinimide acrylate.

[0014] The GelMa is methacrylated gelatin.

[0015] Preferably, in step 2), the mass percentage concentrations of the components in the DST prepolymer solution are: acrylic acid 10-50%; gelatin 10-20%; AAc-NHS ester 1-5%; GelMa 0.1-0.3%; and photoinitiator LAP 0.2-5%.

[0016] Preferably, in step 2), the mass percentage concentrations of the components in the DST prepolymer solution are: acrylic acid 30%; gelatin 10%; AAc-NHS ester 1%; GelMa 0.1%; and photoinitiator LAP 0.2%.

[0017] Preferably, in step 3), the surface modification method of the silica gel substrate is specifically as follows: first, the surface of the cleaned and dried silica gel substrate is treated with glow discharge plasma, then immersed in a BPO-acetone solution, and finally, residual substances on the surface of the silica gel substrate are washed with isopropyl alcohol; the BPO-acetone solution is an acetone solution containing 10% by weight of dimethylbenzene.

[0018] Preferably, the wavelength of the ultraviolet light in step 3) is 365 nm.

[0019] The present invention also provides an application of a PSBMA-DST dual-network hydrogel coating for use as a coating on the inner surface of a silicone suction cup to improve the silicone suction cup's adsorption capacity on organ surfaces. Specifically, it is used as a coating on a liver traction cup.

[0020] The beneficial effects of the present invention are as follows: the PSBMA-DST double-network hydrogel coating prepared by the present invention has a relatively stable swelling rate. When it is applied as a coating on the inner surface of a silicone suction cup, it can slightly swell to fill the fine texture grooves existing in the internal organs or skin, increase the adsorption air tightness, and thus effectively improve the adsorption effect of the silicone suction cup on the internal organs or skin. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is an electron microscope image of the PSBMA-DST double network hydrogel coating in Example 1.

[0022] Figure 2 This is the electron microscope image of the PSBMA hydrogel coating in Comparative Example 1.

[0023] Figure 3 This is the electron microscope image of the DST hydrogel coating in Comparative Example 2.

[0024] Figure 4 This is an electron microscope image of the PSBMA-DST double network hydrogel in Example 2.

[0025] Figure 5 This is the electron microscope image of the PSBMA hydrogel in Comparative Example 3.

[0026] Figure 6 This is the electron microscope image of the DST hydrogel in Comparative Example 4.

[0027] Figure 7 This is a data graph showing the changes in diameter, height and weight of PSBMA-DST prepared in Example 2 in deionized water over time.

[0028] Figure 8 This is a data graph showing the changes in diameter, height and weight of the PSBMA prepared in comparative example 3 in deionized water over time.

[0029] Figure 9 This is a data graph showing the changes in diameter, height and weight of the DST prepared in comparative example 4 in deionized water over time.

[0030] Figure 10 This is a blood compatibility test diagram of PSBMA-DST prepared in Example 2.

[0031] Figure 11 This is a comparison chart of the OD values ​​of PSBMA-DST prepared in Example 2 and the control group.

[0032] Figure 12 Schematic diagram of the PSBMA-DST coating mechanism of Example 1. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below with reference to specific examples, but the present invention is not limited to the following specific examples.

[0034] Example 1

[0035] Preparation of methacryloylated gelatin (GelMa)

[0036] Dissolve 10g of gelatin in 100ml of phosphate buffer, slowly heat to 50°C, and allow to react for 1 hour. Slowly add 2ml of methacrylic anhydride solution dropwise to the solution, maintaining the temperature and allowing to react for 3 hours. Then, add 400ml of phosphate buffer to terminate the reaction. Place the solution in an 8000-14000 kDa dialysis bag and dialyze it in deionized water for 24 hours, changing the deionized water every 6 hours. Continue dialysis for 3-5 days. After dialysis, lyophilize the solution to obtain methacrylated gelatin (GelMa) and store it in a sealed container at -20°C.

[0037] Preparation of SBMA prepolymer solution

[0038] At room temperature, 1 mol / L SBMA monomer was added to 20 ml of deionized water and stirred in a rotary stirrer until fully dissolved. 0.04 mol / L MBAA crosslinker N,N'-methylenebisacrylamide was then added and stirred for 30 minutes to allow for full reaction and crosslinking. 0.001 mol / L ammonium persulfate, a thermal initiator, was then added and stirred for 15 minutes.

[0039] Configuration of DST prepolymer solution

[0040] To prepare gelatin-based DST, acrylic acid, gelatin, AAc-NHS ester, GelMa, and photoinitiator LAP were dissolved in deionized water at room temperature. The weight percentages of each component were: acrylic acid 30%; gelatin 10%; AAc-NHS ester 1%; GelMa 0.1%; and LAP 0.2%. Once completely dissolved, the gel was placed in a nitrogen atmosphere to fully remove oxygen from the interior and then refrigerated at -20°C until ready for use.

[0041] Preparation of coating on silicone suction cup

[0042] To ensure the double-network hydrogel coating adheres tightly to the silicone suction cup, the surface of the silicone suction cup is first modified. The suction cup is then cleaned, soaked in 75% alcohol, and then placed in an ultrasonic cleaner for 30 minutes. After cleaning, it is placed in a 37°C oven until the surface is completely dry. The suction cup is then placed in a glow discharge mass spectrometer for 5 minutes and then soaked in a BPO-acetone solution for 5 minutes. Any residual material is then rinsed with isopropyl alcohol. The BPO-acetone solution contains 10% by weight of dimethylbenzene.

[0043] After cleaning, the silicone sucker was placed in the SBMA prepolymer solution for 1 hour, and then placed in a 60℃ water bath for 1 hour. The treated silicone sucker was then immersed in the DST prepolymer solution and placed in a 4℃ refrigerator for 4 hours. The soaked silicone sucker was taken out and irradiated with 365nm ultraviolet light for 20 minutes, with both sides required to be irradiated for 20 minutes. The obtained PSBMA-DST double network hydrogel coating was obtained by electron microscopy as shown below. Figure 1 and Figure 12 As shown, the silicone rubber and the double-layer hydrogel are tightly bonded. Because the initiator BPO swells within the silicone rubber through immersion, some of the monomers enter the silicone rubber when the silicone rubber is immersed in the SBMA prepolymer solution. Heating then triggers free radical polymerization, forming a PSBMA hydrogel coating bonded to the silicone rubber. Furthermore, the PSBMA-coated silicone rubber is immersed in a DST prepolymer solution, allowing the components of the DST prepolymer to fully penetrate the PSBMA gel network. A photoinitiator then crosslinks and grafts them together, forming a stable and strong double-layer hydrogel coating on the silicone surface.

[0044] Comparative Example 1

[0045] Preparation of SBMA prepolymer solution

[0046] At room temperature, 1 mol / L SBMA monomer was added to 20 ml of deionized water and stirred in a rotary stirrer until fully dissolved. 0.04 mol / L MBAA crosslinker N,N'-methylenebisacrylamide was then added and stirred for 30 minutes to allow for full reaction and crosslinking. 0.001 mol / L ammonium persulfate, a thermal initiator, was then added and stirred for 15 minutes.

[0047] Preparation of coating on silicone suction cup

[0048] First, the surface of the silicone suction cup was modified. After cleaning, the cup was soaked in 75% alcohol and then placed in an ultrasonic cleaner for 30 minutes. After cleaning, the cup was placed in a 37°C oven until the surface was completely dry. The cup was then placed in a glow discharge mass spectrometer for 5 minutes and then soaked in a BPO-acetone solution for 5 minutes. Any remaining material was then rinsed with isopropyl alcohol. The BPO-acetone solution contained 10% by weight of dimethylbenzene.

[0049] After the cleaned silicone suction cup was placed in the SBMA prepolymer solution for 1 hour, it was placed in a 60℃ water bath and heated for 1 hour; the electron microscope image of the obtained PSBMA hydrogel coating is shown in the figure below. Figure 2As shown, a thin layer of PSBMA hydrogel coating can be seen firmly adhering to the silicone rubber surface. This is because the initiator BPO swells within the silicone rubber through immersion. When the silicone rubber is immersed in the SBMA prepolymer solution, some of the monomer enters the silicone rubber. Upon heating, free radical polymerization is initiated, forming a PSBMA hydrogel coating on the surface that bonds to the silicone rubber. However, the resulting PSBMA hydrogel coating is relatively thin.

[0050] Comparative Example 2

[0051] Preparation of methacryloylated gelatin (GelMa)

[0052] Dissolve 10g of gelatin in 100ml of phosphate buffer, slowly heat to 50°C, and allow to react for 1 hour. Slowly add 2ml of methacrylic anhydride solution dropwise to the solution, maintaining the temperature and allowing to react for 3 hours. Then, add 400ml of phosphate buffer to terminate the reaction. Place the solution in an 8000-14000 kDa dialysis bag and dialyze it in deionized water for 24 hours, changing the deionized water every 6 hours. Continue dialysis for 3-5 days. After dialysis, lyophilize the solution to obtain methacrylated gelatin (GelMa) and store it in a sealed container at -20°C.

[0053] Configuration of DST prepolymer solution

[0054] Dissolve acrylic acid, gelatin, AAc-NHS ester, GelMa, and photoinitiator LAP in deionized water at room temperature. The weight percentages of each component are: acrylic acid 30%; gelatin 10%; AAc-NHS ester 1%; GelMa 0.1%; and photoinitiator LAP 0.2%. Once completely dissolved, place the gel under nitrogen to fully remove oxygen from the gel and refrigerate at -20°C until ready to use.

[0055] Preparation of coating on silicone suction cup

[0056] First, the surface of the silicone suction cup was modified. After cleaning, the cup was soaked in 75% alcohol and then placed in an ultrasonic cleaner for 30 minutes. After cleaning, the cup was placed in a 37°C oven until the surface was completely dry. The cup was then placed in a glow discharge mass spectrometer for 5 minutes and then soaked in a BPO-acetone solution for 5 minutes. Any remaining material was then rinsed with isopropyl alcohol. The BPO-acetone solution contained 10% by weight of dimethylbenzene.

[0057] The cleaned silicone suction cup was placed in DST prepolymer solution and soaked in a 4°C refrigerator for 4 hours. The soaked silicone suction cup was taken out and irradiated with ultraviolet light of 365 nm for 20 minutes. Both sides needed to be irradiated for 20 minutes. The electron microscope image of the obtained DST hydrogel coating is shown in the figure below. Figure 3As shown in the figure, no obvious coating phenomenon is observed on the silicone rubber surface. This is because the macromolecules in the DST prepolymer solution have difficulty entering the swollen silicone rubber surface and polymerizing with the initiator inside it to form a stable hydrogel coating structure.

[0058] Example 2

[0059] The base silicone suction cup in Example 1 was replaced with a 2 mm × 20 mm × 20 mm silicone sheet. The other conditions were the same as in Example 1 to prepare a silicone sheet coated with a PSBMA-DST double network hydrogel coating. The sample was denoted as PSBMA-DST. The electron microscope image is shown in FIG. Figure 4 shown.

[0060] Comparative Example 3

[0061] The base silicone suction cup in Comparative Example 1 was replaced with a 2 mm × 20 mm × 20 mm silicone sheet. The other conditions were the same as those in Comparative Example 1 to prepare a silicone sheet coated with PSBMA hydrogel coating. The sample was denoted as PSBMA. The electron microscope image is shown in FIG. Figure 5 shown.

[0062] Comparative Example 4

[0063] The base silicone suction cup in Comparative Example 2 was replaced with a 2 mm × 20 mm × 20 mm silicone sheet. The other conditions were the same as those in Comparative Example 2 to prepare a silicone sheet coated with a DST hydrogel coating. The sample was denoted as DST. The electron microscope image is shown in FIG. Figure 6 shown.

[0064] Comparative test of coating swelling rate

[0065] The PSBMA-DST, PSBMA and DST prepared in Example 2 and Comparative Examples 3-4 were placed in deionized water, and the diameter, height and weight were measured and recorded at 0 hour, 1 hour, 3 hours, 5 hours, 7 hours, 9 hours and 12 hours respectively. Figure 7 As shown in Figure 3, the diameter, height, and weight of PSBMA-DST increased slowly, showing good swelling properties, and the texture hardly changed after soaking; Figure 8 As shown in Figure 3, the diameter, height, and weight of PSBMA showed a decrease, which may be due to the removal of incomplete cross-linked substances, and the enhanced interaction between zwitterionic groups due to hydration, which reduced the swelling rate and made the gel coating texture softer; Figure 9 As shown in Figure 3, DST hydrogel exhibits excessive swelling and its texture gradually becomes brittle after swelling.

[0066] Hemolysis test

[0067] Hemolysis test: Figure 10As shown, the positive control (water) was dark, while PSBMA-DST was colorless, similar to the negative control. The dissolution rates of PSBMA-DST were 2.00%, indicating that the PSBMA-DST hydrogel had good blood compatibility.

[0068] Biocompatibility

[0069] In vitro biocompatibility testing was performed using PSBMA-DST prepared in Example 2 for cell culture. PSBMA-DST was incubated in 1 ml of Dulbecco's modified Eagle's medium (DMEM) at 37°C for 24 hours. Original DMEM was used as a control. NiH3T3 cells were seeded in a 96-well plate (n = 10 for DST-conditioned medium; n = 10 for DMEM). The cells were then treated with DST-conditioned medium and incubated at 37°C in a 5% CO2 incubator for 24 hours. 110 μl of complete medium containing CCK-8 reagent was added to each well and incubated in the incubator for 2 hours. The OD value was measured at 450 nm using a microplate reader. Figure 11 As shown, the cytocompatibility of PSBMA-DST was investigated by direct contact assay with NiH3T3 cells. After 1, 2, and 3 days of co-incubation, the cell viability of the PSBMA-DST group was not significantly different from that of the control group, indicating that PSBMA-DST has no cytotoxic effect.

[0070] The above are only examples of the features of the present invention and do not constitute any limitation on the scope of protection of the present invention. Any technical solution formed by equivalent exchange or equivalent replacement falls within the scope of protection of the present invention.

Claims

1. A method for preparing a double-network hydrogel coating, characterized in that: The following steps are involved: 1) Add SBMA monomer to deionized water, stir and dissolve, then add crosslinking agent and stir to make it react and crosslink, and finally add thermal initiator and stir to obtain SBMA prepolymer solution; 2) Dissolve acrylic acid, gelatin, AAc-NHS ester, GelMa and photoinitiator LAP in deionized water, and deoxygenate after complete dissolution to obtain DST prepolymer solution; 3) After surface modification, the silicone substrate is immersed in the SBMA prepolymer solution for a predetermined period of time, and then heated in a water bath at 60-65° C. for a predetermined period of time; then, the silicone substrate is removed and immersed in the DST prepolymer solution for a predetermined period of time; finally, the soaked silicone substrate is removed and irradiated under ultraviolet light for a predetermined period of time to produce a double network hydrogel coating; The mass percentage concentration of each component in the DST prepolymer solution is: acrylic acid 10-50%; gelatin 10-20%; AAc-NHS ester 1-5%; GelMa 0.1-0.3%; photoinitiator LAP 0.2-5%; In step 3), the surface modification method of the silica gel substrate is specifically as follows: first, the surface of the cleaned and dried silica gel substrate is treated with glow discharge plasma, then immersed in a BPO-acetone solution, and finally, residual substances on the surface of the silica gel substrate are washed with isopropyl alcohol; the BPO-acetone solution is an acetone solution with a mass percentage of dimethylbenzene oxide.

2. The method for preparing a double-network hydrogel coating according to claim 1, wherein: The cross-linking agent is N,N'-methylenebisacrylamide.

3. The method for preparing a double network hydrogel coating according to claim 1, wherein: The thermal initiator is ammonium persulfate.

4. The method for preparing a double network hydrogel coating according to claim 1, wherein: In step 2), the mass percentage concentrations of the components in the DST prepolymer solution are: acrylic acid 30%; gelatin 10%; AAc-NHS ester 1%; GelMa 0.1%; and photoinitiator LAP 0.2%.

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