A high-concentration and high-viscosity injectable soft tissue filling material and its preparation method and use

Abstract

The present invention belongs to the technical field of biomedical materials, and specifically relates to a high-concentration and high-viscosity injectable soft tissue filling material, its preparation method and use. The soft tissue filling material of the present invention is made by mixing an amphiphilic degradable polyether-polyester copolymer with water and annealing it; the process conditions of the annealing are: under the protection of an inert gas, pressurizing it to 1-3 bar, heating it to 110-130 ° C, slowly cooling it to room temperature, and reducing the pressure to standard atmospheric pressure while cooling it. Experimental tests have shown that the soft tissue filling material of the present invention has excellent properties such as high concentration, high particle size and viscosity, good formulation stability, good stability between process batches, good needle permeability, no need for sterilization process, good safety, long-term retention effect in the body, and the ability to promote skin tissue collagen production. It has good application effects in the fields of wound healing, tissue filling and / or repair, wrinkle removal and anti-aging.

Description

Technical Field

[0001] The present invention belongs to the technical field of biomedical materials, and in particular relates to a high-concentration and high-viscosity injectable soft tissue filling material, a preparation method thereof, and uses thereof. Background Art

[0002] Regenerative tissue fillers are an important treatment for burns, pressure sores, trauma, tissue loss and deformation, and anti-aging. They offer the advantages of minimal invasiveness, minimal tissue damage, and a quick recovery time. Currently, regenerative tissue fillers on the market primarily consist of polymer microspheres and a gel carrier. Commonly used polymer microspheres include polycaprolactone (PCL) and polylactic acid (PLA) microspheres, while gel carriers primarily consist of hyaluronic acid (HA) and carboxymethyl cellulose (CMC) gels. These fillers stimulate collagen production in the skin, improving its texture and appearance, resulting in a natural and long-lasting filler effect.

[0003] Although biodegradable polymer microspheres have shown great potential in clinical applications, they also face a series of problems and challenges. First, the insufficient hydrophilicity of the polymer makes it difficult to disperse and preserve it in aqueous solution for a long time, and it needs to be mixed before injection, which increases the operation time of medical staff. Second, during the injection process, particles of different particle sizes move unevenly under the pressure applied by the syringe plunger, which may cause blockage of the injection needle lumen. Finally, massage is needed after injection to ensure that the filler is evenly diffused in the skin tissue. Otherwise, it may not only lead to the formation of long-term lumps, but also may cause serious side effects such as granulomas.

[0004] Amphiphilic block copolymers based on materials such as PCL, PLA and PLGA can effectively solve the problems of difficult dispersion / dissolution and easy aggregation of polymer microspheres due to their good hydrophilicity. Currently, the existing technology mainly uses common methods such as solvent volatilization, dialysis, melt hydration, freeze-thaw method, etc. to prepare these amphiphilic block copolymers into self-assembly preparations, thereby improving the encapsulation efficiency, stability and bioavailability of drugs, while improving the release behavior of drugs and achieving more precise therapeutic effects. However, the self-assembly preparations prepared by existing methods usually have problems such as low concentration, small particle size and low viscosity. This makes it easy to diffuse and be rapidly metabolized after injection in the body, thereby limiting the durability and support of the filling effect. In addition, during the production process, the formation process of the self-assembly is subject to the complex influence of kinetic and thermodynamic factors, resulting in significant differences in the stability of the prepared self-assembly preparations between batches, which poses a challenge to large-scale production and quality control. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a high-concentration and high-viscosity injectable soft tissue filling material, a preparation method and use thereof.

[0006] A high-concentration and high-viscosity injectable soft tissue filling material is prepared by mixing an amphiphilic degradable polyether-polyester copolymer with water and annealing the mixture;

[0007] The annealing process conditions are: under inert gas protection, pressurized to 1-3 bar, heated to 110-130° C., slowly cooled to room temperature, and reduced pressure to standard atmospheric pressure while cooling.

[0008] Preferably, the amphiphilic degradable polyether-polyester copolymer is a block copolymer consisting of a polyether block and a polyester block;

[0009] The polyether block is selected from at least one of polyethylene glycol or its derivatives;

[0010] The polyester block is selected from at least one of polycaprolactone, poly (L-lactic acid), poly (D-lactic acid), poly (racemic) lactic acid or poly (lactic acid-glycolic acid copolymer).

[0011] Preferably, the amphiphilic degradable polyether-polyester copolymer is a diblock copolymer or a triblock copolymer consisting of a polyether block and a polyester block;

[0012] The mass ratio of the polyether block to the polyester block in the amphiphilic degradable polyether-polyester copolymer is 1:1-1:5, preferably 1:2-1:3;

[0013] The weight average molecular weight of the amphiphilic degradable polyether-polyester copolymer is selected from 5000-100000 Da, preferably 10000-50000 Da.

[0014] Preferably, the weight average molecular weight of the polyether block is selected from 2000-20000 Da; the weight average molecular weight of the polyester block is selected from 2500-80000 Da.

[0015] Preferably, the polyether block is selected from at least one of polyethylene glycol 2000, polyethylene glycol 2500, polyethylene glycol 4000, polyethylene glycol 6000, polyethylene glycol 8000, polyethylene glycol 10000, polyethylene glycol monomethyl ether 2000, polyethylene glycol monomethyl ether 5000, polyethylene glycol monomethyl ether 10000, and polyethylene glycol monomethyl ether 20000;

[0016] The polyester block is selected from at least one of polycaprolactone 2500, polycaprolactone 5000, polycaprolactone 10000, polycaprolactone 15000, polycaprolactone 20000, polycaprolactone 25000, polycaprolactone 30000, polylactic acid-glycolic acid copolymer 10000, polyracemic lactic acid 10000, poly(L-lactic acid) 15000, polylactic acid-glycolic acid copolymer 15000, polycaprolactone 25000, poly(D-lactic acid) 40000, and poly(L-lactic acid) 80000.

[0017] Preferably, the feeding ratio of the amphiphilic degradable polyether-polyester copolymer to water is 1-5 kg:10 L.

[0018] Preferably, the annealing process conditions are: under inert gas protection, pressurized to 1.5-2 bar, heated to 110-120 ° C, slowly cooled to room temperature, and reduced to standard atmospheric pressure while cooling.

[0019] And / or, the annealing process conditions further include: the pressurized heating process is maintained for 10-20 minutes; the process of slowly cooling to room temperature and releasing the pressure to standard atmospheric pressure is completed within 30-60 minutes;

[0020] And / or, the mixing method is selected from one of the following methods:

[0021] Method 1: heating the amphiphilic degradable polyether-polyester copolymer to 60-95°C until it is completely melted, and adding water at 60-95°C and mixing;

[0022] Method 2: heating the amphiphilic degradable polyether-polyester copolymer to 60-95°C to melt, cooling it to form small pieces or granules, and adding water at 60-95°C to mix;

[0023] Method 3: dissolving the amphiphilic degradable polyether-polyester copolymer in an organic solvent, adding water dropwise to the resulting solution under stirring, fully dispersing the mixture, and then volatilizing the organic solvent to obtain the product;

[0024] Method 4: dissolving the amphiphilic degradable polyether-polyester copolymer in an organic solvent, adding the obtained solution dropwise into water under stirring, fully dispersing the solution, and obtaining the product after the organic solvent evaporates.

[0025] Preferably, the concentration of the soft tissue filling material is 15-40 wt. %, preferably 15-35 wt. % ;

[0026] The viscosity of the soft tissue filling material is 100-1000 mPa·s, preferably 278-429 mPa·s.

[0027] The present invention also provides a method for preparing the above-mentioned high-concentration and high-viscosity injectable soft tissue filling material, comprising the following steps:

[0028] The amphiphilic degradable polyether-polyester copolymer is mixed with water and annealed;

[0029] The annealing process conditions are: under inert gas protection, pressurized to 1-3 bar, heated to 110-130° C., slowly cooled to room temperature, and reduced pressure to standard atmospheric pressure while cooling.

[0030] The present invention also provides use of the high-concentration and high-viscosity injectable soft tissue filling material in the preparation of medicines, cosmetics or medical aesthetic materials.

[0031] The drug has at least one of the following effects: promoting wound healing, tissue filling, promoting tissue repair, wrinkle removal, and anti-aging;

[0032] The cosmetic or medical cosmetic material has at least one of the following functions: tissue filling, promoting tissue repair, wrinkle removal, and anti-aging.

[0033] The present invention performs annealing treatment on an amphiphilic degradable polyether-polyester copolymer solution to prepare an injectable soft tissue filling material, which has the following advantages:

[0034] (1) The high-concentration and high-viscosity injectable filling material provided by the present invention has a higher content of active ingredients than conventional commercially available filling materials, thereby having a better filling effect.

[0035] (2) Compared with traditional preparations, the high-concentration and high-viscosity injectable filling material provided by the present invention has higher stability at the same concentration of active ingredients, can avoid aggregation and precipitation of the solution, and has a longer storage and effective time.

[0036] (3) The method for preparing the high-concentration, high-viscosity injectable filler provided by the present invention does not significantly increase the viscosity of the solution by adding other substances. The high viscosity allows for excellent immediate filling and retention time, while maintaining excellent needle permeability. During injection, the material has a more stable pushing force, which facilitates the injection operation and allows the use of a thinner needle, reducing pain for the recipient.

[0037] (4) The preparation method of the high-concentration and high-viscosity injectable filling material provided by the present invention is simple, and in the preferred embodiment, no organic solvent is used. The material has good batch stability and is suitable for large-scale production.

[0038] (5) The high-concentration and high-viscosity injectable filling material provided by the present invention has better biocompatibility and storage stability, and avoids the complex sterilization process and its impact on the properties of the filling material.

[0039] Obviously, based on the above contents of the present invention, according to common technical knowledge and customary means in this field, without departing from the above basic technical ideas of the present invention, other various forms of modifications, replacements or changes can be made.

[0040] The following further describes the above content of the present invention in detail through specific embodiments in the form of examples. However, this should not be construed as limiting the scope of the above subject matter of the present invention to the following examples. All technologies implemented based on the above content of the present invention fall within the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 These are optical images of the high-concentration and high-viscosity injectable filling materials obtained in Examples 1-7 and the injectable filling material obtained in Comparative Example 1.

[0042] Figure 2 This is a TEM image of the high-concentration and high-viscosity injectable filling material obtained in Example 1.

[0043] Figure 3 The particle size and viscosity of the high-concentration and high-viscosity injectable filling material obtained in different batches of Example 1 are shown.

[0044] Figure 4 The particle size and viscosity of the high-concentration and high-viscosity injectable filling material obtained in different batches of Comparative Example 1 are shown.

[0045] Figure 5 The curves of particle size change over time of the high-concentration and high-viscosity injectable filling materials obtained in Example 1 and Comparative Example 1 are shown.

[0046] Figure 6 This is a pushing force curve of the high-concentration and high-viscosity injectable filling material obtained in Example 1-2.

[0047] Figure 7 Graph showing the in vivo diffusion of the injectable filling materials obtained in Example 1 and Comparative Example 1.

[0048] Figure 8 Graph showing the collagen content in rat back skin after the high-concentration and high-viscosity injectable filling materials obtained in Examples 1-7 and the injectable filling material obtained in Comparative Example 1 were injected into rat skin. DETAILED DESCRIPTION

[0049] In the following examples and experimental examples, reagents and raw materials not specifically described are all commercially available. In the following examples, polyether raw materials, such as MPEG5000, PEG5000, MPEG20000, MPEG2000, and MPEG5000, were purchased from Shanghai Myrrel Biochemical Technology Co., Ltd.

[0050] Example 1:

[0051] This embodiment provides polyethylene glycol monomethyl ether 5000-polycaprolactone 25000 (MPEG 5000 -PCL 25000 ) Preparation of high-concentration and high-viscosity injectable filling material, the preparation steps are as follows:

[0052] 1.00 kg of polyethylene glycol monomethyl ether 5000 (MPEG5000) and 5 kg of ε-caprolactone (ε-CL) were added to a reactor. After azeotropic removal of water, stannous octoate was added and the reaction was carried out at 130 °C for 60 h. After the reaction was completed, it was dissolved in dichloromethane and washed with distilled water and brine. The organic phase was dried and precipitated with ether, and then placed in an oven to dry to constant weight to obtain the product. The NMR integrated area of ​​3.38 ppm (attributable to the methoxy protons on the MPEG backbone) and 4.07 ppm (attributable to the methylene protons on the PCL backbone) was calculated from the NMR spectrum, confirming that the product was MPEG. 5000 -PCL 25000 Copolymer.

[0053] 4.00 kg MPEG 5000 -PCL 25000 The copolymer was added to a reactor and heated to 60°C. Once completely melted, 10 L of 60°C distilled water was added, stirred thoroughly, and then cooled to room temperature. Nitrogen was introduced into the reactor, pressurized to 1.5 bar, and heated to 120°C for 10 minutes. The temperature was then slowly lowered to room temperature over a 30-minute cooling period. During this cooling period, the pressure was simultaneously reduced to standard atmospheric pressure, yielding a highly concentrated, highly viscous injectable filler material.

[0054] Example 2:

[0055] This example provides polycaprolactone 2500-polyethylene glycol 5000-polycaprolactone 2500 (PCL 2500 -PEG 5000 -PCL 2500 ) Preparation of high-concentration and high-viscosity injectable filling material, the preparation steps are as follows:

[0056] 3.00 kg of polyethylene glycol 5000 (PEG5000) and 3.01 kg of ε-caprolactone (ε-CL) were added to a reactor. After azeotropic removal of water, stannous octoate was added and the reaction was carried out at 125 °C for 60 h. After the reaction was completed, it was dissolved in dichloromethane and washed with distilled water and brine. The organic phase was dried and precipitated with ether, then placed in an oven to dry to constant weight to obtain the product. The NMR integrated area of ​​3.64 ppm (attributable to the ethoxy protons on the MPEG backbone) and 4.07 ppm (attributable to the methylene protons on the PCL backbone) was calculated from the NMR spectrum, confirming that the product was PCL. 2500 -PEG 5000-PCL 2500 Copolymer.

[0057] 5.00 kg PCL 2500 -PEG 5000 -PCL 2500 The material was fully melted at 70°C and cooled to form small pieces or granules. The material was then added to a reactor, and 10 L of 70°C distilled water was added. After thorough soaking and stirring, the mixture was cooled to room temperature. Nitrogen was introduced into the reactor, pressurized to 1.5 bar, and heated to 110°C for 15 minutes. The temperature was then slowly lowered to room temperature over a 35-minute cooling period. During this cooling period, the pressure was simultaneously reduced to standard atmospheric pressure, yielding a highly concentrated and highly viscous injectable filler material.

[0058] Example 3:

[0059] This embodiment provides polyethylene glycol monomethyl ether 20000-poly L-lactic acid 80000 (MPEG 20000 -PLLA 80000 ) Preparation of high-concentration and high-viscosity injectable filling material, the preparation steps are as follows:

[0060] 1.00 kg of polyethylene glycol monomethyl ether 20000 (MPEG20000) and 4.01 kg of L-lactide (L-LA) were added to a reactor. After azeotropic removal of water, stannous octoate was added and the mixture was reacted at 140 °C for 60 h. After the reaction was completed, it was dissolved in dichloromethane and washed with distilled water and brine. The organic phase was dried and precipitated with ether, then placed in an oven to dry to constant weight to obtain the product. The NMR integrated area of ​​3.38 ppm (attributable to the methoxy protons on the MPEG main chain) and 1.58 ppm (attributable to the methyl protons on the LA side chain) was calculated from the NMR spectrum, confirming that the product was MPEG. 20000 -PLLA 80000 Copolymer.

[0061] 1.25 kg MPEG 20000 -PLLA 80000 Dissolve the solution in 10 L of acetone, then add 5 L of distilled water and stir to disperse evenly. After the acetone has completely evaporated, introduce nitrogen gas to a pressure of 2 bar, heat to 130°C, and maintain this temperature for 20 minutes. Then, slowly cool the solution to room temperature over a 40-minute cooling period. During this cooling period, the pressure is simultaneously reduced to standard atmospheric pressure to yield a highly concentrated, highly viscous injectable filler material.

[0062] Example 4:

[0063] This embodiment provides polyethylene glycol monomethyl ether 2000-poly (D-lactic acid 3000) 2000 -PDLA 3000) Preparation of high-concentration and high-viscosity injectable filling material, the preparation steps are as follows:

[0064] 1.00 kg of polyethylene glycol monomethyl ether 2000 (MPEG2000) and 1.51 kg of D-lactide (D-LA) were added to the reactor. After azeotropic removal of water, stannous octoate was added and the mixture was reacted at 130 °C for 55 h. After the reaction was completed, it was dissolved in dichloromethane and washed with brine and distilled water. The organic phase was dried and precipitated with ether, then placed in an oven and dried to constant weight to obtain the product. The NMR integrated area of ​​3.38 ppm (attributable to the methoxy protons on the MPEG main chain) and 1.58 ppm (attributable to the methyl protons on the LA side chain) was calculated by NMR spectrum, confirming that the product was MPEG. 2000 -PDLA 3000 Copolymer.

[0065] 2.00 kg MPEG 2000 -PDLA 3000 Dissolve the mixture in 10 L of tetrahydrofuran, then add the solution to 10 L of distilled water and disperse it evenly by ultrasonication. After the tetrahydrofuran has completely evaporated, introduce argon into the reactor, pressurize it to 2.5 bar, heat it to 125°C, and maintain it for 20 minutes. The temperature is then slowly lowered to room temperature over a 45-minute cooling period. During this cooling phase, the pressure is simultaneously reduced to standard atmospheric pressure to yield a highly concentrated, highly viscous injectable filler material.

[0066] Example 5:

[0067] This embodiment provides polyethylene glycol monomethyl ether 5000-poly (ethylene glycol monomethyl ether) 10000 (MPEG 5000 -PDLLA 10000 ) Preparation of high-concentration and high-viscosity injectable filling material, the preparation steps are as follows:

[0068] 2.00 kg of polyethylene glycol monomethyl ether 5000 (MPEG5000) and 4.01 kg of DL-lactide (DL-LA) were added to the reactor. After azeotropic removal of water, stannous octoate was added and the reaction was carried out at 140 °C for 72 h. After the reaction was completed, it was dissolved in dichloromethane and washed with brine and distilled water respectively. The organic phase was dried and precipitated with ether, and then placed in an oven to dry to constant weight to obtain the product. The NMR integrated area of ​​3.38 ppm (attributable to the methoxy protons on the MPEG main chain) and 1.58 ppm (attributable to the methyl protons on the LA side chain) was calculated by NMR spectrum, confirming that the product was MPEG. 5000 -PDLLA 10000 Copolymer.

[0069] 3.00 kg MPEG 5000 -PDLLA10000 The copolymer was added to a reactor and heated to 80°C. Once completely melted, 10 L of 80°C distilled water was added, stirred thoroughly, and cooled to room temperature. Nitrogen was introduced into the reactor to pressurize it to 2 bar, and the mixture was heated to 115°C and held there for 20 minutes. The temperature was then slowly lowered to room temperature over a 50-minute cooling period. During this cooling period, the pressure was simultaneously reduced to standard atmospheric pressure, yielding a highly concentrated, highly viscous injectable filler material.

[0070] Example 6:

[0071] This embodiment provides polyethylene glycol monomethyl ether 5000-polylactic acid-co-glycolic acid 15000 (MPEG 5000 -PLGA 15000 ) Preparation of high-concentration and high-viscosity injectable filling material, the preparation steps are as follows:

[0072] 1.00 kg of polyethylene glycol monomethyl ether 5000 (MPEG5000) and 3.01 kg of DL-lactide (DL-LA) and glycolide (GA) were added to the reactor. After azeotropic removal of water, stannous octoate was added and the reaction was carried out at 125 °C for 65 h. After the reaction was completed, it was dissolved in dichloromethane and washed with brine and distilled water respectively. The organic phase was dried and precipitated with ether, and then placed in an oven to dry to constant weight to obtain the product. The nuclear magnetic integration area of ​​3.38 ppm (attributed to the methoxy protons on the MPEG main chain), 1.58 ppm (attributed to the methyl protons on the LA side chain), and 4.80 ppm (attributed to the methylene protons on the GA chain) was calculated by NMR spectrum, confirming that the product was MPEG. 5000 -PLGA 15000 Copolymer.

[0073] 3.50 kg MPEG 5000 -PLGA 15000 The copolymer was fully melted at 90°C and cooled to form small pieces or pellets. The copolymer was then added to a reactor, where 10 L of 90°C distilled water was added. After thorough soaking and stirring, the mixture was cooled to room temperature. Nitrogen was introduced into the reactor, pressurized to 2 bar, and heated to 110°C for 20 minutes. The temperature was then slowly lowered to room temperature over a 55-minute cooling period. During this cooling phase, the pressure was simultaneously reduced to standard atmospheric pressure, yielding a highly concentrated and highly viscous injectable filler material.

[0074] Example 7:

[0075] This embodiment provides polyethylene glycol monomethyl ether 2000-polylactic acid-glycolic acid copolymer 10000-polyethylene glycol monomethyl ether 2000 (MPEG 2000 -PLGA 10000 -MPEG 2000) Preparation of high-concentration and high-viscosity injectable filling material, the preparation steps are as follows:

[0076] 2.00 kg of polyethylene glycol monomethyl ether 2000 (MPEG2000) and 5.01 kg of DL-lactide (DL-LA) and glycolide (GA) were added to a reactor. After azeotropic removal of water, stannous octoate was added and the reaction was carried out at 130°C for 60 h. After completion of the reaction, the mixture was dissolved in dichloromethane and washed with brine and distilled water. The organic phase was dried and precipitated with ether before being dried in an oven to constant weight to obtain the product. The NMR integrated areas of 3.38 ppm (attributable to methoxy protons on the MPEG backbone), 1.58 ppm (attributable to methyl protons on the LA side chain), and 4.80 ppm (attributable to methylene protons on the GA chain) were calculated from the NMR spectrum. The product was confirmed to be polyethylene glycol monomethyl ether 2000-poly(lactic-co-glycolic acid) 50000 (MPEG2000). 2000 -PLGA 5000 ).

[0077] 5.00 kg MPEG 2000 -PLGA 5000 Hexamethylene diisocyanate (HDI) was added to the reactor, and stannous octoate was added, and the reaction was carried out at 130 ° C for 48 hours. After the reaction was completed, the product was precipitated with ether and placed in an oven to dry to constant weight to obtain the product. The NMR integrated area of ​​3.38 ppm (attributed to the methoxy protons on the MPEG main chain), 1.58 ppm (attributed to the methyl protons on the LA side chain), and 4.80 ppm (attributed to the methylene protons on the GA chain) was calculated by NMR spectrum, confirming that the product was MPEG. 2000 -PLGA 10000 -MPEG 2000 Copolymer.

[0078] 3.80 kg MPEG 2000 -PLGA 10000 -MPEG 2000 Melt at 95°C and cool to form small pieces or granules. Then, add the mixture to a reactor, add 10 L of 95°C distilled water, soak thoroughly, stir, and cool to room temperature. Nitrogen is introduced into the reactor, pressurized to 2 bar, heated to 120°C, and held there for 20 minutes. The mixture is then slowly cooled to room temperature over a 55-minute cooling period. During this cooling period, the pressure is simultaneously reduced to standard atmospheric pressure, yielding a highly concentrated, highly viscous injectable filler material.

[0079] Comparative Example 1:

[0080] This comparative example provides polyethylene glycol monomethyl ether 5000-polycaprolactone 25000 (MPEG 5000 -PCL25000 ) Preparation of injectable filling material, the preparation steps are as follows:

[0081] MPEG was prepared in the same manner as in Example 1. 5000 -PCL 25000 .

[0082] 4.00 kg MPEG 5000 -PCL 25000 The copolymer was added to a reactor and heated to 60°C. After it was completely melted, 10 L of 60°C distilled water was added. After stirring, the mixture was cooled to room temperature to obtain an injectable filling material.

[0083] Compared with Example 1, the main difference of this comparative example is that no annealing step is performed.

[0084] The following experiments further illustrate the technical solution of the present invention. The samples used are all samples prepared in Examples 1-7 and Comparative Example 1.

[0085] Test Example 1: Solid content test

[0086] The high-concentration and high-viscosity injectable filling materials prepared in Examples 1-7 and Comparative Example 1 were freeze-dried and their solid contents were measured. Each example was tested three times. The results are shown in Table 1. The testing method is as follows:

[0087] A certain mass of sample was weighed, completely frozen, and then freeze-dried using a freeze dryer. The mass of the freeze-dried solid was weighed, and the solid content was calculated. As shown in Table 1, the high-concentration, high-viscosity injectable filling materials prepared in Examples 1-7 had a solid content of up to 33.20%, which is higher than commercially available polymer microsphere filling materials, indicating that the method proposed in this patent can produce injectable filling materials with higher concentrations.

[0088] Table 1 Solid content of high-concentration and high-viscosity injectable filling materials prepared in Examples 1-7 and Comparative Example 1

[0089] Test Example 2: Morphology Observation

[0090] A small amount of the high-concentration and high-viscosity injectable filling materials prepared in Examples 1-7 and Comparative Example 1 was placed in a vial and an optical image was taken using a mobile phone camera. Figure 1 As shown, the high-concentration and high-viscosity injectable filling materials prepared in Examples 1-7 are uniform white transparent liquid preparations, which are free of impurities when observed under natural light. The injectable material prepared in Comparative Example 1 is lighter in color and has a lower viscosity.

[0091] Take a small amount of the high-concentration and high-viscosity injectable filling material prepared in Example 1, dilute it evenly and observe it using TEM. Figure 2 As shown, the high-concentration and high-viscosity injectable filling material prepared in Example 1 forms uniform spherical nanoparticles.

[0092] Test Example 3: Particle size and viscosity test

[0093] Particle size test: Take 10 μL of sample, dilute 100 times with purified water, shake well, and add to the test dish. Use Malvern Zetasizer Nano ZS dynamic light scattering instrument to measure according to the "Pharmacopoeia of the People's Republic of China" (Particle size and particle size distribution determination method (0982 third method)).

[0094] Viscosity test: Take 10 mL of sample and test it using a rotational rheometer at (25±0.2)℃ and a shear rate of 100 (1 / s).

[0095] Table 2 shows the particle size and viscosity test results for the preparations obtained in Examples 1-7 and Comparative Example 1. The preparation prepared in Comparative Example 1 had a particle size of 151.91 nm and a viscosity of 78.21 mPa·s. The preparations prepared in Examples 1-7 all had particle sizes greater than 200 nm and viscosities greater than 300 mPa·s, demonstrating that the method provided by the present invention successfully prepared injectable filling materials with larger particle sizes and higher viscosities.

[0096] Table 2 Particle size and viscosity of high-concentration and high-viscosity injectable filling materials obtained in Examples 1-7 and Comparative Example 1

[0097]

[0098] Test Example 4: Preparation Stability

[0099] The particle size and viscosity stability of the preparations obtained in Example 1 and Comparative Example 1 between batches, as well as the particle size stability after long-term storage, were tested. The particle size and viscosity test methods were the same as those in Test Example 3. Example 1 was repeated 6 times. Figure 3 As shown in Figure 1, the particle size of the obtained injection filler varies in the range of 225-242 nm, and the viscosity is in the range of 364-395 mPa·s. The experimental results show that the particle size and viscosity of the high-concentration and high-viscosity injectable filler prepared by the method provided in Example 1 are stable, with good batch stability, and are suitable for large-scale, standardized production. Figure 4 As shown, its particle size and viscosity vary greatly, its properties are unstable, and it is not conducive to production.

[0100] The injection filling materials prepared in Example 1 and Comparative Example 1 were placed in a constant temperature and humidity chamber, and samples were taken out at regular intervals for particle size testing. The specific testing method was the same as that in Test Example 3. Figure 5As shown, during the 12-month test period, the particle size of the sample prepared in Example 1 fluctuated slightly around 235 nm, indicating that its particle size remained essentially unchanged and the preparation properties were stable. However, the particle size of the sample prepared in Comparative Example 1 decreased significantly over time, from 151.91 nm to 122.09 nm, indicating that the preparation properties were unstable, which would affect its actual use after long-term storage.

[0101] Test Example 5: Needle-passing

[0102] The high-concentration and high-viscosity injectable filling material obtained in Example 1-2 was placed in a 1 mL syringe and subjected to a pushing force test using a 27 G injection needle (two samples were prepared in parallel). The pushing force curve is shown in FIG. Figure 6 The results show that the pushing force remained within the range of 12-14 N throughout the injection process, with minimal fluctuations. Furthermore, the injection material did not accumulate at the needle tip during the later stages of injection, preventing an increase in injection force. This demonstrates that the highly concentrated, highly viscous injectable filling material prepared by the method provided by this patent has excellent needle permeability, facilitating clinical procedures for physicians.

[0103] Test Example 6: Colony Count

[0104] The determination shall be carried out in accordance with the gel method in Section 1143 of the General Rules of the Chinese Pharmacopoeia, Volume IV, Test for Bacterial Endotoxins, and the results shall comply with the provisions in Section 2.2.12. The determination shall be carried out in accordance with the direct inoculation method in Section 1101 of the General Rules of the Chinese Pharmacopoeia, Volume IV, Test for Sterility, and the results shall comply with the provisions in Section 2.2.13.

[0105] The results showed that the bacterial endotoxin content of the high-concentration, high-viscosity injectable filling materials obtained in Examples 1-7 was all below 0.5 EU / g, meeting national standards. Sterility tests also confirmed sterility, meeting the requirements for enterprise production, product marketing approval, and quality management. However, the bacterial colony count in Comparative Example 1 was above 0.5 EU / g and failed the sterility test.

[0106] The results of this example show that the high-concentration and high-viscosity injectable filling material prepared by the present invention can be used without going through a complicated sterilization process, thereby avoiding the influence of the sterilization process on the properties of the injectable filling material.

[0107] Test Example 7: Diffusion Experiment

[0108] In vivo imaging was used to test the retention time of the high-concentration, high-viscosity injectable filler materials obtained in Examples 1-7 and Comparative Example 1 in the dorsal skin of rats. The high-concentration, high-viscosity injectable filler materials obtained in Examples 1-7 and Comparative Example 1 were first coupled with FITC fluorescent molecules to prepare fluorescently labeled injection solutions, which were then injected into the dorsal skin of six-week-old SD rats. The diffusion of the fluorescently labeled injection solutions in the rat skin was tracked using in vivo imaging, and the imaging results are shown in Figure 2. Figure 7The results show that the fluorescence of the high-concentration, high-viscosity injectable filler material of Example 1 completely disappeared after approximately 5 months, while the fluorescence of the injectable filler material of Comparative Example 1 completely disappeared after approximately 2 months. This indicates that the injectable filler material prepared in Examples 1-7, Comparative Example 1, has a longer in vivo retention effect.

[0109] Test Example 8: Filling Effect

[0110] The high-concentration and high-viscosity injectable filling materials prepared in Examples 1-7 and the injectable filling material prepared in Comparative Example 1 were injected intradermally into the dermis of the back skin of 8-week-old SD rats. The back skin was taken for Masson staining analysis. The results were as follows: Figure 8 The results show that compared with the injectable filling material prepared in Comparative Example 1, the high-concentration and high-viscosity injectable filling materials prepared in Examples 1-7 can more effectively promote the production of collagen in skin tissue and achieve better filling effects.

[0111] The above embodiments and experimental examples demonstrate that the present invention produces an injectable soft tissue filler material that has undergone high-temperature and high-pressure annealing treatment. The material exhibits excellent properties, including high concentration, high particle size and viscosity, good formulation stability, good stability between process batches, good needle permeability, no need for sterilization, good safety, long-term retention in the body, and the ability to promote collagen production in skin tissue. The material has excellent application effects in the fields of wound healing, tissue filling and / or repair, wrinkle removal, and anti-aging.

Claims

1. A high-concentration and high-viscosity injectable soft tissue filling material, characterized in that: It is made by mixing an amphiphilic degradable polyether-polyester copolymer with water and annealing it; The annealing process conditions are: under inert gas protection, pressurized to 1-3 bar, heated to 110-130° C., slowly cooled to room temperature, and reduced pressure to standard atmospheric pressure while cooling.

2. The high-concentration and high-viscosity injectable soft tissue filling material according to claim 1, characterized in that: The amphiphilic degradable polyether-polyester copolymer is a block copolymer consisting of a polyether block and a polyester block; The polyether block is selected from at least one of polyethylene glycol or its derivatives; The polyester block is selected from at least one of polycaprolactone, poly (L-lactic acid), poly (D-lactic acid), poly (racemic) lactic acid or poly (lactic acid-glycolic acid copolymer).

3. The high-concentration and high-viscosity injectable soft tissue filling material according to claim 2, characterized in that: The amphiphilic degradable polyether-polyester copolymer is a diblock copolymer or a triblock copolymer consisting of a polyether block and a polyester block; The mass ratio of the polyether block to the polyester block in the amphiphilic degradable polyether-polyester copolymer is 1:1-1:5; The weight average molecular weight of the amphiphilic degradable polyether-polyester copolymer is selected from 5000-100000 Da.

4. The high-concentration and high-viscosity injectable soft tissue filling material according to claim 3, characterized in that: The weight average molecular weight of the polyether block is selected from 2000-20000 Da; the weight average molecular weight of the polyester block is selected from 2500-80000 Da.

5. The high-concentration and high-viscosity injectable soft tissue filling material according to any one of claims 2 to 4, characterized in that: The polyether block is selected from at least one of polyethylene glycol 2000, polyethylene glycol 2500, polyethylene glycol 4000, polyethylene glycol 6000, polyethylene glycol 8000, polyethylene glycol 10000, polyethylene glycol monomethyl ether 2000, polyethylene glycol monomethyl ether 5000, polyethylene glycol monomethyl ether 10000, and polyethylene glycol monomethyl ether 20000; The polyester block is selected from at least one of polycaprolactone 2500, polycaprolactone 5000, polycaprolactone 10000, polycaprolactone 15000, polycaprolactone 20000, polycaprolactone 25000, polycaprolactone 30000, polylactic acid-glycolic acid copolymer 10000, polyracemic lactic acid 10000, poly(L-lactic acid) 15000, polylactic acid-glycolic acid copolymer 15000, polycaprolactone 25000, poly(D-lactic acid) 40000, and poly(L-lactic acid) 80000.

6. The high-concentration and high-viscosity injectable soft tissue filling material according to claim 1, characterized in that: The feeding ratio of the amphiphilic degradable polyether-polyester copolymer to water is 1-5 kg:10 L.

7. The high-concentration and high-viscosity injectable soft tissue filling material according to claim 1, characterized in that: The annealing process conditions are: under inert gas protection, pressurized to 1.5-2 bar, heated to 110-120 ° C, slowly cooled to room temperature, and reduced to standard atmospheric pressure while cooling. And / or, the annealing process conditions further include: the pressurized heating process is maintained for 10-20 minutes; the process of slowly cooling to room temperature and releasing the pressure to standard atmospheric pressure is completed within 30-60 minutes; And / or, the mixing method is selected from one of the following methods: Method 1: Heat the amphiphilic biodegradable polyether-polyester copolymer to 60-95°C and completely melt it, then add water at 60-95°C and mix; Method 2: heating the amphiphilic degradable polyether-polyester copolymer to 60-95°C to melt, cooling it to form small pieces or granules, and adding water at 60-95°C to mix; Method 3: dissolving the amphiphilic degradable polyether-polyester copolymer in an organic solvent, adding water dropwise to the resulting solution under stirring, fully dispersing the mixture, and then volatilizing the organic solvent to obtain the product; Method 4: dissolving the amphiphilic degradable polyether-polyester copolymer in an organic solvent, adding the obtained solution dropwise into water under stirring, fully dispersing the solution, and obtaining the product after the organic solvent evaporates.

8. The high-concentration and high-viscosity injectable soft tissue filling material according to claim 1, characterized in that: The concentration of the soft tissue filling material is 15-40 wt. %; The viscosity of the soft tissue filling material is 100-1000 mPa·s.

9. The method for preparing the high-concentration and high-viscosity injectable soft tissue filling material according to any one of claims 1 to 8, characterized in that: The steps include: The amphiphilic degradable polyether-polyester copolymer is mixed with water and annealed; The annealing process conditions are: under inert gas protection, pressurized to 1-3 bar, heated to 110-130° C., slowly cooled to room temperature, and reduced pressure to standard atmospheric pressure while cooling.

10. Use of the high-concentration and high-viscosity injectable soft tissue filling material according to any one of claims 1 to 8 in the preparation of medicines, cosmetics or medical aesthetic materials, characterized in that: The drug has at least one of the following effects: promoting wound healing, tissue filling, promoting tissue repair, wrinkle removal, and anti-aging; The cosmetic or medical cosmetic material has at least one of the following functions: tissue filling, promoting tissue repair, wrinkle removal, and anti-aging.

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