Double-network soft tissue filling medical hydrogel, preparation method therefor, and use thereof

Abstract

A double-network soft tissue filling medical hydrogel, a preparation method therefor, and a use thereof. The hydrogel comprises the following components: L-polyglutamic acid, polylysine, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, N-hydroxysuccinimide, and calcium chloride dihydrate. The hydrogel has good and controllable mechanical properties, and has a controllable in-vivo degradation rate.

Description

A double-network soft tissue filling medical hydrogel and its preparation method and application Technical Field

[0001] The present invention relates to the technical field of medical hydrogels for soft tissue filling, in particular to the field of IPC C08G65, and more specifically to a double-network medical hydrogel for soft tissue filling, and a preparation method and application thereof. Background Art

[0002] The most commonly used material for the preparation of biomimetic soft tissue substitutes in research and development both domestically and internationally is polymer hydrogel. Polymer hydrogels are composed of a network of polymers and water, and possess strong water absorption, swelling, thixotropy, syneresis, elasticity, and biocompatibility. The advantages of soft tissue filler injections are simple, minimally invasive procedures and significant therapeutic effects. However, currently used soft tissue filler materials still have several drawbacks. For example, microsphere-based soft tissue fillers such as polytetrafluoroethylene microspheres, silicone resin microspheres, and ceramic microspheres are prone to migration, particularly within cavitary soft tissues, necessitating secondary injections to enhance efficacy. While autologous fat injections offer excellent biocompatibility, they are rapidly reabsorbed in the body and have a short-lived efficacy. Natural polymer hydrogels such as hyaluronic acid and collagen, while biocompatible, are subject to degradation by enzymes in the body, resulting in a shorter efficacy period.

[0003] Bulkamid, a foreign product, has been approved in the United States as a soft tissue filler for patients with urinary incontinence. Its mechanical properties are similar to those of human soft tissue and it has good clinical effects. However, the monomer of its main component, polyacrylamide, is toxic, and the purification process for the synthetic material is very demanding. Adverse events caused by raw material purity issues have been widely reported, posing a high safety risk.

[0004] CN102093576B discloses a method for preparing polyvinyl alcohol hydrogel. This method is simple to operate and easy to implement, and parameters can be adjusted according to the characteristics of different tissues, making it easy to obtain. The biomimetic soft tissue material prepared using this method is stable, easy to store, and recyclable, but its mechanical properties are still not high enough.

[0005] Therefore, in view of the above situation, it is necessary to develop a medical hydrogel for filling soft tissue with good material safety, mechanical properties consistent with the properties of human soft tissue, and the ability to be stable for a long time in the body.

[0006] Summary of the Invention

[0007] The first aspect of the present invention provides a double-network soft tissue filling medical hydrogel, comprising: L-polyglutamic acid and polylysine, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl), N-hydroxysuccinimide (NHS), and calcium chloride dihydrate.

[0008] A second aspect of the present invention provides a method for preparing a double-network soft tissue filling medical hydrogel, comprising the following steps:

[0009] Step 1, dissolving L-polyglutamic acid in a morpholineethanesulfonic acid solution to obtain solution A;

[0010] Step 2, dissolving polylysine in morpholineethanesulfonic acid solution to obtain solution B;

[0011] Step 3: Add the above solution B dropwise to solution A and mix well to obtain a mixed system C for later use;

[0012] Step 4, dissolving 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride in morpholineethanesulfonic acid solution to obtain solution D;

[0013] Step 5, dissolving N-hydroxysuccinimide in morpholineethanesulfonic acid solution to obtain solution E;

[0014] Step 6: dissolving calcium chloride dihydrate in deionized water to obtain solution F;

[0015] Step 7: Take solution D, solution E, and solution F and add them dropwise to system C. After stirring, dialyze in pure water to obtain the product.

[0016] The mass concentration percentage of the L-polyglutamic acid is 3-15%, preferably 10%.

[0017] The mass concentration percentage of the polylysine is 1-3%, preferably 2.5%.

[0018] The mass concentration percentage of the EDC·HCl and NHS is 0.04-0.24%, preferably 0.2%.

[0019] The mass concentration percentage of the calcium chloride dihydrate is 0-0.06%, preferably 0.048%.

[0020] The concentration of the morpholineethanesulfonic acid solution is 0.05-0.5 mol / L.

[0021] The weight ratio of the L-polyglutamic acid to polylysine is (4-10):1.

[0022] The applicants have discovered that a weight ratio of L-polyglutamic acid to polylysine of (4-10):1 can effectively improve the mechanical properties of the hydrogel. This is likely due to the fact that the L-polyglutamic acid and polylysine bond to form a single-network polymer system with "long-chain multi-arm" characteristics. This polymer, after further chelation with a chelating agent, forms a dual-network system. However, when the L-polyglutamic acid content is too low, precipitation tends to occur, and the hydrogel does not form. Further research has found that a volume ratio of solution D, solution E, and solution F of (0.2-0.5):(0.2-0.5):(0.25-1) can further improve the swelling degree of the hydrogel and simultaneously regulate the degradation rate. It is possible that the activators 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC·HCl) and N-hydroxysuccinimide (NHS) activate the -COOH in polyglutamic acid, which then forms an amide bond with the -NH2 of polylysine, forming the first layer of cross-linked network; calcium chloride then forms a chelate bond with the free -COOH in polyglutamic acid, forming the second layer of cross-linked network. The combined effect of the two networks effectively improves the overall performance of the hydrogel.

[0023] Preferably, the weight ratio of L-polyglutamic acid to polylysine is (4-8):1.

[0024] The volume ratio of solution D, solution E and solution F is (0.2-0.5):(0.2-0.5):(0.25-1).

[0025] Preferably, the volume ratio of solution D, solution E and solution F is 0.5:0.5:(0.5-1).

[0026] The solid content of the hydrogel is 15-30 wt%.

[0027] Preferably, the solid content of the hydrogel is 15-25 wt%.

[0028] The swelling degree of the hydrogel is ≥100%.

[0029] Preferably, the swelling degree of the hydrogel is ≥200%.

[0030] More preferably, the swelling degree of the hydrogel is ≥300%.

[0031] The degradation time of the hydrogel is 3-20 days.

[0032] Preferably, the degradation time of the hydrogel is 7-12 days.

[0033] The third aspect of the present invention provides an application of a method for preparing a double-network soft tissue filling medical hydrogel, which can be used as a soft tissue filling material in medical aesthetic facial filling, stress urinary incontinence, fecal incontinence, vesicoureteral reflux and esophageal reflux. Beneficial effects

[0034] 1. The weight ratio of L-polyglutamic acid to polylysine is (4-10):1, which can effectively improve the mechanical properties of the hydrogel.

[0035] 2. The volume ratio of solution D, solution E and solution F is (0.2-0.5):(0.2-0.5):(0.25-1), which can further increase the swelling degree of the hydrogel and regulate the degradation rate.

[0036] 3. The volume ratio of solution D, solution E and solution F is 0.5:0.5:(0.5-1), and the swelling degree of the hydrogel is ≥300%.

[0037] 4. The solid content of the hydrogel is 15-30 wt %, which is conducive to the formation of double network hydrogel and can be injected and filled, meeting the requirements of the injectable biomedical field for hydrogel performance.

[0038] 5. The hydrogel of the present invention has good controllable mechanical properties and a degradation rate of 3-20 days, and can be used as a soft tissue filling material in the medical field. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is the hydrogel prepared in Example 4

[0040] Figure 2 is a diagram of the hydrogel prepared in Example 4 injected through a needle

[0041] Figure 3 is a graph showing the viscoelasticity of the hydrogel prepared in Example 1.

[0042] Figure 4 is a graph showing the viscoelasticity of the hydrogel prepared in Example 4.

[0043] Figure 5 is a graph showing the viscoelasticity of the hydrogel prepared in Example 15. DETAILED DESCRIPTION

[0044] Below in conjunction with embodiment, embodiment of the present invention is described in detail, but those skilled in the art will appreciate that the following implementation is only for illustrating the present invention and should not be considered as limiting the scope of the present invention. Specific conditions are not indicated in the examples, and are carried out according to conventional conditions or the conditions recommended by the manufacturer. Reagents and instruments used are not indicated by the manufacturer and can be purchased from the market.

[0045] Example 1-18: A double-network soft tissue filling medical hydrogel.

[0046] Comparative Example 1: 5% hyaluronic acid solution.

[0047] The raw materials for preparation are shown in Table 1:

[0048] Table 1

[0049] The L-polyglutamic acid has a molecular weight of 700,000 and is provided by Shanghai Aladdin Biochemical Technology Co., Ltd.; the polylysine model is P192512, with a molecular weight of 2,000-5,000, and is provided by Shanghai Aladdin Biochemical Technology Co., Ltd.; the EDC·HCl and NHS are provided by Shanghai Aladdin Biochemical Technology Co., Ltd.

[0050] Among them, Example 1 is a method for preparing a double-network soft tissue filling medical hydrogel, which comprises the following steps:

[0051] Step 1: dissolving L-polyglutamic acid in a morpholineethanesulfonic acid (MES) solution to obtain a solution A, wherein the mass fraction of L-polyglutamic acid in the solution A is as shown in Table 1, and the solution A is set aside;

[0052] Step 2: dissolving polylysine in MES solution to obtain solution B. The mass fraction of polylysine in solution B is shown in Table 1 and set aside.

[0053] Step 3: Add the above solution B dropwise to solution A and mix well to obtain a mixed system C for later use;

[0054] Step 4: Dissolve 0.5 g of EDC·HCl in 2 g of MES solution to obtain solution D, which is set aside.

[0055] Step 5: Dissolve 0.5 g of NHS in 2 g of MES solution to obtain solution E, which is set aside.

[0056] Step 6: Take solution D and solution E respectively, add them dropwise to system C, stir for 5 minutes, and dialyze in pure water at room temperature for 24 hours to obtain the product.

[0057] The concentration of the morpholineethanesulfonic acid solution is 0.1 mol / L, and the solvent is water.

[0058] Among them, embodiments 2-5, 8-17 are methods for preparing a double-network soft tissue filling medical hydrogel, comprising the following steps:

[0059] Step 1: dissolving L-polyglutamic acid in a morpholineethanesulfonic acid (MES) solution to obtain a solution A, wherein the mass fraction of L-polyglutamic acid in the solution A is as shown in Table 1, and the solution A is set aside;

[0060] Step 2: dissolving polylysine in MES solution to obtain solution B. The mass fraction of polylysine in solution B is shown in Table 1 and set aside.

[0061] Step 3: Add the above solution B dropwise to solution A and mix well to obtain a mixed system C for later use;

[0062] Step 4: Dissolve 0.5 g of EDC·HCl in 2 g of MES solution to obtain solution D, which is set aside.

[0063] Step 5: Dissolve 0.5 g of NHS in 2 g of MES solution to obtain solution E, which is set aside.

[0064] Step 6: Dissolve 0.56 g of CaCl2·2H2O in 10 mL of deionized water to obtain solution F.

[0065] Step 7: Take solution D, solution E, and solution F respectively and add them dropwise to system C. After stirring for 5 minutes, dialyze in pure water at room temperature for 24 hours to obtain the product.

[0066] The concentration of the morpholineethanesulfonic acid solution is 0.1 mol / L, and the solvent is water.

[0067] The CaCl2·2H2O was provided by Shanghai Aladdin Biochemical Technology Co., Ltd.

[0068] The hydrogel prepared in Example 4 is shown in FIG1 , and can be injected through a needle ( FIG2 ).

[0069] Among them, embodiments 6, 7, and 18 are methods for preparing a double-network soft tissue filling medical hydrogel, comprising the following steps:

[0070] Step 1: dissolving L-polyglutamic acid in a morpholineethanesulfonic acid (MES) solution to obtain a solution A, wherein the mass fraction of L-polyglutamic acid in the solution A is as shown in Table 1, and the solution A is set aside;

[0071] Step 2: dissolving polylysine in MES solution to obtain solution B. The mass fraction of polylysine in solution B is shown in Table 1 and set aside.

[0072] Step 3: Add the above solution B dropwise to solution A, mix evenly, and obtain a mixed system C with precipitation.

[0073] The preparation method of the hydrogel in Comparative Example 1 is as follows: 0.5 g of hyaluronic acid is added to 9.95 g of water while stirring to obtain a colloidal medium.

[0074] Performance testing methods

[0075] The following tests were performed on the hydrogels of Examples 1-18 and Comparative Example 1. The test results are shown in Table 2:

[0076] 1. Swelling rate

[0077] The specific implementation method is: add 10 times the mass of PBS solution to the reagent bottle containing the gel system, and swell at 37°C for 24 hours. The swelling rate formula is: Swelling rate = (mass after swelling - mass before swelling) / mass before swelling * 100%

[0078] 2. Degradation rate

[0079] The specific implementation method is: add 10 times the mass of PBS solution into the reagent bottle containing the gel system, and regularly observe and record the mass of the gel at 37°C, where "-" means no degradation test was performed.

[0080] 3. Viscoelasticity tests were performed on Examples 1, 4, and 15, and the test graphs are shown in Figures 3-5.

[0081] The specific implementation method is: the sample is treated at a constant temperature of 37° C., and then placed in a rotational rheometer to test the storage modulus and loss modulus of the sample at 0.1-1000 Hz.

[0082] Performance test data

[0083] Table 2

[0084] Comparative Examples 6, 7, 12, and 18 all showed polyamino acid agglomeration and precipitation when polyglutamic acid and polylysine were mixed. This indicates that the content of polyglutamic acid in the double-network hydrogel system described herein cannot be less than 4 times that of polylysine.

[0085] Comparing Examples 14, 16, and 3, it can be considered that the substance contents of Examples 14 and 16 are 80% and 90% of that of Example 3, respectively. Based on the curing conditions of the two, it can be considered that the solid content in the double-network viscoelastic hydrogel cannot be lower than the solid content described in Example 16;

Claims

1. A double-network soft tissue filling medical hydrogel, characterized in that, The components include: L - polyglutamic acid, polylysine, 1 - ethyl - (3 - dimethylaminopropyl) carbodiimide hydrochloride, N - hydroxysuccinimide, and calcium chloride dihydrate.

2. A preparation method of the double - network soft - tissue filling medical hydrogel according to claim 1, comprising the following steps: Step 1, dissolve L - polyglutamic acid in a morpholineethanesulfonic acid solution to obtain solution A; Step 2, dissolve polylysine in a morpholineethanesulfonic acid solution to obtain solution B; Step 3, drop the above - mentioned solution B into solution A, and after mixing evenly, obtain a mixed system C; Step 4, dissolve 1 - ethyl - (3 - dimethylaminopropyl) carbodiimide hydrochloride in a morpholineethanesulfonic acid solution to obtain solution D; Step 5, dissolve N - hydroxysuccinimide in a morpholineethanesulfonic acid solution to obtain solution E; Step 6, dissolve calcium chloride dihydrate in deionized water to obtain solution F; Step 7, drop solution D, solution E, and solution F into the mixed system C, stir, and then dialyze in pure water to obtain the product.

3. The preparation method of a double-network soft tissue filling medical hydrogel according to claim 2, wherein, The concentration of the morpholineethanesulfonic acid solution is 0.05 - 0.5 mol / L.

4. The preparation method of a double-network soft tissue filling medical hydrogel according to claim 3, characterized in that, The weight ratio of L - polyglutamic acid to polylysine is (4 - 10):

1.

5. The preparation method of a double-network soft tissue filling medical hydrogel according to claim 4, characterized in that, The weight ratio of L - polyglutamic acid to polylysine is (4 - 8):

1.

6. The preparation method of a double-network soft tissue filling medical hydrogel according to claim 5, characterized in that, The volume ratio of solution D, solution E, and solution F is (0.2 - 0.5):(0.2 - 0.5):(0.25 - 1).

7. The preparation method of a double-network soft tissue filling medical hydrogel according to claim 6, characterized in that, The volume ratio of solution D, solution E, and solution F is 0.5:0.5:(0.5 - 1).

8. The preparation method of a double-network soft tissue filling medical hydrogel according to claim 7, characterized in that, The swelling degree of the hydrogel is ≥100%.

9. The preparation method of a double-network soft tissue filling medical hydrogel according to claim 8, characterized in that, The degradation time of the hydrogel is 3 - 20 days.

10. Use of a method for preparing a double-network soft tissue filling medical hydrogel according to any one of claims 2-9, characterized in that, It is used as a soft - tissue filling material in one of the following medical aesthetic applications: facial filling, stress urinary incontinence, fecal incontinence, vesicoureteral reflux, and esophageal reflux.

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