Injection complex liquid containing hyaluronic acid microspheres, and preparation method and application thereof

Abstract

This invention relates to an injectable composite solution containing microspheres, its preparation method, and its uses, belonging to the field of medical aesthetics. The injectable composite solution of this invention comprises the following components by weight: 1-20 parts hyaluronic acid microspheres, 1-12 parts non-crosslinked sodium hyaluronate, 0.1-3 parts collagen, and 0.1-3 parts elastin. This composite solution exhibits system stability, long-lasting effect, and does not produce the Tyndall effect when used for facial injection.

Description

Technical Field

[0001] This invention belongs to the field of medical biomaterials technology, and more specifically relates to an injectable composite solution containing hyaluronic acid microspheres, a method for preparing the injectable composite solution, and its application in the field of medical aesthetics. Background Technology

[0002] As people age, their skin undergoes aging due to both internal and external factors. The body's cells lose the ability to synthesize hyaluronic acid (HA), and the amount of collagen and elastin synthesized decreases, leading to reduced skin elasticity and increased roughness. This results in skin aging, wrinkles, increased skin fragility, and diminished repair function. Therefore, supplementing the dermis with nutrients such as hyaluronic acid, collagen, and elastin can replenish skin moisture, restore elasticity, and improve skin condition, thereby smoothing wrinkles and achieving a more even complexion.

[0003] Hyaluronic acid, also known as hyaluronic acid, is a high-molecular-weight mucopolysaccharide composed of glucuronic acid and N-acetylglucosamine disaccharide units. It is a major component of human dermal tissue and a crucial element for skin hydration. Due to its unique molecular structure, hyaluronic acid can firmly lock water molecules within its special double-helix columnar structure, preventing moisture loss and thus possessing exceptional hydrating and moisturizing properties, earning it the title of an ideal natural moisturizing factor. However, uncrosslinked hyaluronic acid has a short lifespan in the body, being completely degraded by hyaluronidase within 1-2 days, only providing hydration and moisturizing functions for a short period. Therefore, to prolong its lifespan, crosslinking agents are often used to crosslink it. However, modified hyaluronic acid gels tend to swell, and crosslinked hyaluronic acid often suffers from uneven crosslinking, irregular particle morphology, and inconsistent particle size, which can easily cause side effects such as redness and swelling when injected into the face due to surface irregularities. Furthermore, hyaluronic acid gels crosslinked with chemical crosslinking agents have a certain degree of support, making them less likely to diffuse at the injection site and potentially forming bumps. Therefore, it can only be used for injections at deeper levels of the face and is not suitable for moisturizing the superficial dermis.

[0004] Patent CN 115177561 A, "An Injectable Anti-aging, Wrinkle-reducing, and Whitening Composite Solution Formulation and Its Preparation Method and Application," provides a method for preparing a composite solution formulation. This formulation comprises hyaluronic acid, collagen powder, collagen peptides, glutathione, vitamin C, a combination of traditional Chinese medicine extracts, and phosphate buffer. However, unmodified hyaluronic acid is easily degraded in vivo, providing only short-term hydration and moisturizing functions. Patent CN 115990286 A, "An Injectable Poly-L-lactic Acid Composite Agent and Its Preparation Method," describes the preparation of an injectable composite agent using poly-L-lactic acid particles, non-crosslinked hyaluronic acid, and mannitol. However, this technology suffers from problems due to the hyaluronic acid being combined with other types of microsphere filler materials. This not only results in poor biocompatibility of the microspheres and difficulty in in vivo degradation, but also makes dispersion difficult and the dispersion uniformity uncontrollable, leading to poor system stability because hyaluronic acid and microspheres are two different materials.

[0005] In summary, there is a need to develop an injection compound solution that is more stable, has a longer duration of action, and can be used for injection into the superficial or middle dermis of the skin. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides an injectable composite solution containing hyaluronic acid microspheres, its preparation method, and its applications. The injectable composite solution of this invention utilizes hyaluronic acid, collagen, and elastin to form a composite network, thereby enhancing the stability of the composite solution system containing hyaluronic acid microspheres. The microspheres are uniformly dispersed in the solution system and can be stably maintained.

[0007] The first aspect of the present invention provides an injectable composite solution, characterized in that, by weight, the injectable composite solution comprises 1-20 parts of hyaluronic acid microspheres, 1-12 parts of non-crosslinked sodium hyaluronate, 0.1-3 parts of collagen, and 0.1-3 parts of elastin.

[0008] The hyaluronic acid microspheres used in this invention are cross-linked emulsified hyaluronic acid microspheres with a particle size of 2-8 μm, such as... Figure 1 As shown, these hyaluronic acid microspheres are round and spherical with a smooth, edgeless surface and relatively uniform particle size, which can reduce side effects such as redness and swelling during facial injections. Furthermore, these microspheres are formed by cross-linking hyaluronic acid, exhibiting good biocompatibility and being completely degraded and absorbed by the body using hyaluronidase. These microspheres can be used for subcutaneous injection. The cross-linked nature of the microspheres extends their retention time in the body, and because their cross-linking is denser and has a more suitable particle size compared to cross-linked hyaluronic acid gel, they exhibit virtually no swelling. Moreover, when used for injectable fillers, they do not produce the Tyndall effect, achieving long-lasting hydration and moisturizing effects.

[0009] Collagen is another major component of the extracellular matrix. Adult skin primarily contains type I and type III collagen, with type III collagen being key to maintaining youthful skin. Type I collagen is larger and relatively firm, determining the skin's structural framework, while type III collagen is smaller, more elastic, and determines skin suppleness. Furthermore, the amount of type III collagen in adult skin decreases with age, and the adult dermis no longer has the ability to synthesize type III collagen, only type I. Therefore, intradermal injection of type III collagen directly replenishes the body's lost type III collagen, supplying the dermis with essential nutrients, improving skin elasticity, and enhancing skin condition. The collagen used in this invention is injectable recombinant humanized type III collagen (RHCIII), obtained by transferring the original natural collagen gene sequence into engineered cells using recombinant gene technology, followed by fermentation and purification. It is lower in cost, safer, less allergenic, and more compatible with humans than animal-derived collagen, and carries no risk of transmitting animal-derived diseases.

[0010] Elastin is a major component of elastic fibers and another major component of the extracellular matrix. Elastic fibers coexist with collagen fibers, maintaining the elasticity and tensile strength of skin tissue. The cross-linking between elastin molecules is more complex than that of collagen, forming an elastic network structure through cross-linking involving lysine residues. This covalently linked network can generate elasticity through conformational changes, allowing the skin to stretch and fold, and is responsible for maintaining and supporting skin elasticity. Elastin is a major cause of skin aging, leading to sagging, drooping, and fine wrinkles. With natural skin aging, the breakdown of elastic fibers becomes increasingly significant. Currently, elastin is mainly extracted from animal tissues, which carries drawbacks such as the risk of viral transmission and easy degradation. Recombinant human elastin is obtained by gene construction based on the amino acid sequence of the active site in elastin, expressed and purified using a yeast expression system. Recombinant human elastin is composed of human elastin fragments and has a secondary structure and reversible phase transition properties similar to natural elastin. It is safer and less allergenic than animal-derived elastin collagen. Therefore, intradermal injection to directly supplement the skin with recombinant elastin can maintain youthful, delicate, and elastic skin, and improve skin condition.

[0011] Furthermore, since hyaluronic acid, collagen, and elastin all possess hydrophilic groups such as hydroxyl groups on their molecules, when these three are used together as a carrier to load hyaluronic acid microspheres, they can bind together through hydrogen bonds and van der Waals forces to form a stable carrier network. Moreover, because both the hyaluronic acid and the hyaluronic acid microspheres in the system use the same hyaluronic acid component, the hyaluronic acid microspheres can exist uniformly in the system, resulting in high system stability. The inventors unexpectedly discovered that the ratio of non-crosslinked sodium hyaluronate, collagen, and elastin in the injectable composite solution affects the performance of the injectable composite solution (e.g., stability, resistance to enzymatic degradation), and through extensive experiments, they determined the optimal mass fraction range of each component used in the injectable composite solution of this invention, enabling the injectable composite solution of this invention to achieve optimal performance.

[0012] Optionally, the injectable compound solution comprises 5-20 parts of hyaluronic acid microspheres, 5-12 parts of non-crosslinked sodium hyaluronate, 0.1-3 parts of collagen, and 0.1-3 parts of elastin.

[0013] Optionally, the injectable compound further comprises a hyaluronidase inhibitor; preferably, the hyaluronidase inhibitor is 0.5-1.5 parts by weight.

[0014] Optionally, the injectable compound may further contain other functional components, including antioxidants, preferably 0.1-3 parts by weight.

[0015] Optionally, the antioxidant is selected from one or more of glutathione, mannitol, vitamin C, resveratrol, citric acid, and sorbitol.

[0016] Hyaluronic acid degradation is related to hyaluronidase, temperature, or oxygen free radicals. Therefore, adding enzyme inhibitors and antioxidants to the system can delay the degradation time of hyaluronic acid microspheres in vivo, achieving a longer maintenance time. The hyaluronidase inhibitor of this invention uses an amino acid component, such as arginine, glycine, or alanine, which not only has excellent inhibitory properties on hyaluronidase activity and is safe and reliable, but also effectively replenishes the nutrients needed by the skin while inhibiting hyaluronidase activity, thus possessing good medical and cosmetic value. The antioxidants, such as mannitol, niacinamide, and glutathione, all have good antioxidant properties and can be used to limit free radical damage to the skin, reduce and minimize the loss of hyaluronic acid and collagen, and slow down the degradation of the injected product.

[0017] A second aspect of the present invention provides a method for preparing the above-mentioned injection composite solution, characterized by comprising the following steps:

[0018] (1) Dissolve collagen and elastin in buffer solution to obtain solution A;

[0019] (2) Dissolve hyaluronic acid microspheres and non-crosslinked sodium hyaluronate in buffer solution to obtain solution B;

[0020] (3) Mix solution A and solution B to obtain solution C;

[0021] (4) Solution C is sterilized and then filled to obtain the injection compound solution.

[0022] Steps (1) and (2) above can be performed in any order, either sequentially or simultaneously, and are not bound by the order of the numbers.

[0023] Optionally, step (1) further includes dissolving hyaluronidase inhibitors and / or other functional ingredients in a buffer solution; the functional ingredients include antioxidants.

[0024] Optionally, the buffer solution is a phosphate buffer solution.

[0025] After extensive preliminary experiments, the inventors of this invention ultimately developed a method to prepare the injectable composite solution by separately dissolving collagen, elastin, hyaluronic acid microspheres, and non-crosslinked hyaluronic acid before mixing them. Compared to dissolving all the above substances simultaneously in the same solution, this preparation method allows for a more uniform distribution of hyaluronic acid microspheres in the solution, resulting in a more stable injectable composite solution and preventing subsequent solution stratification.

[0026] A third aspect of the present invention provides the application of the above-described injection compound solution in the preparation of products injected into the dermis layer of the skin. Preferably, the application of the above-described injection compound solution in the preparation of products injected into the superficial or middle dermis layer of the skin is provided. For example, the product of the present invention can be used as a facial hyaluronic acid injection solution.

[0027] The present invention has the following beneficial effects:

[0028] 1. This invention mixes non-crosslinked hyaluronic acid solutions with hyaluronic acid microspheres. By mixing hyaluronic acid microspheres with non-crosslinked hyaluronic acid, collagen, elastin, and optionally hyaluronidase inhibitors and antioxidants, a composite solution for facial injection is prepared. The hyaluronic acid microspheres are formed through micro-crosslinking emulsification, resulting in improved anti-degradation properties compared to non-crosslinked hyaluronic acid. Furthermore, the hyaluronidase inhibitors and antioxidants can delay the degradation of hyaluronic acid, reducing the degradation of hyaluronic acid components in the composite solution by enzymes and free radicals, significantly improving the maintenance time of the composite solution in vivo, and allowing it to be injected into the superficial layers of the face to exert excellent moisturizing properties.

[0029] 2. Recombinant collagen and recombinant elastin can bind with non-crosslinked hyaluronic acid through hydrogen bonds and van der Waals forces to form a relatively stable spatial network system. Hyaluronic acid microspheres can be uniformly dispersed in this system, making the composite solution system more uniform and stable. Furthermore, the moisturizing effect of hyaluronic acid in the composite solution synergistically improves skin condition with the repairing effects of recombinant collagen and elastin. In addition, the hyaluronidase inhibitor in the composite solution provided by this invention uses amino acid components, which have no pharmacological effects, are safe and effective, and the addition of amino acids can replenish the nutrients needed by the skin.

[0030] 3. Due to their opaque nature, hyaluronic acid microspheres make the composite solution opaque overall, which can avoid the Tyndall effect after injection into areas such as around the eyes when used for facial injection. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0032] Figure 1 This is a photograph showing the particle size distribution of the hyaluronic acid microspheres used in this invention.

[0033] Figure 2 This is a photograph of the final product obtained in Embodiment 2 of the present invention.

[0034] Figure 3 Images of the product obtained in Example 2 of this invention after 24 weeks of storage and images of the product obtained in Comparative Example 1 after 24 weeks of storage. Detailed Implementation

[0035] The present invention will be further described below with reference to embodiments. It should be understood that the embodiments are only used to further illustrate and explain the present invention, and are not intended to limit the present invention.

[0036] Unless otherwise defined, the technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art. Although similar or identical methods and materials may be applied in experimental or practical applications, materials and methods are described herein. In case of conflict, the definitions included herein shall prevail. Furthermore, materials, methods, and examples are for illustrative purposes only and are not restrictive.

[0037] Hyaluronic acid microspheres: purchased from Shaanxi Future Biomatrix Co., Ltd. Particle size 2-8 μm, formed through emulsification cross-linking, with a cross-linking degree of 0.5%-1.5%.

[0038] Non-crosslinked sodium hyaluronate: purchased from Shandong Zhongshan Biotechnology Co., Ltd., product number / batch number: SH06221225-19.

[0039] Recombinant collagen: purchased from Interfil Biopharmaceuticals Research Institute Co., Ltd., batch number 20221214-2.

[0040] Recombinant elastin: purchased from Interfil Bioproducts Research Institute Co., Ltd.

[0041] Example 1

[0042] This embodiment provides an injectable composite solution containing 8 mg / mL non-crosslinked sodium hyaluronate, 12 mg / mL hyaluronic acid microspheres, 1 mg / mL recombinant collagen, and 1 mg / mL recombinant elastin.

[0043] The preparation method consists of the following steps:

[0044] Step 1: Prepare 0.9% phosphate buffer solution to obtain solution A.

[0045] Step 2: Divide solution A into two parts. Dissolve recombinant collagen and recombinant elastin in one part of solution A to obtain solution B.

[0046] Step 3: Dissolve non-crosslinked sodium hyaluronate and hyaluronic acid microspheres in another portion of solution A to obtain solution C.

[0047] Step 4: Mix solution B and solution C and stir well to obtain solution D.

[0048] Step 5: After sterilization, solution D is filled into vials to obtain the injectable composite solution.

[0049] Example 2

[0050] This embodiment provides an injectable composite solution containing 8 mg / mL non-crosslinked sodium hyaluronate, 12 mg / mL hyaluronic acid microspheres, 1 mg / mL recombinant collagen, 1 mg / mL recombinant elastin, 0.5 mg / mL arginine, 0.5 mg / mL glycine, and 1 mg / mL mannitol.

[0051] The preparation method consists of the following steps:

[0052] Step 1: Prepare 0.9% phosphate buffer solution to obtain solution A.

[0053] Step 2: Divide solution A into two parts. Dissolve arginine, glycine, mannitol, recombinant collagen, and recombinant elastin in a portion of solution A to obtain solution B.

[0054] Step 3: Dissolve non-crosslinked sodium hyaluronate and hyaluronic acid microspheres in another portion of solution A to obtain solution C.

[0055] Step 4: Mix solution B and solution C and stir well to obtain solution D.

[0056] Step 5: After sterilization, solution D is filled into vials to obtain the injectable composite solution.

[0057] Example 3

[0058] This embodiment provides an injectable composite solution containing 10 mg / mL non-crosslinked sodium hyaluronate, 10 mg / mL hyaluronic acid microspheres, 1 mg / mL recombinant collagen, 1 mg / mL recombinant elastin, 0.5 mg / mL alanine, 0.5 mg / mL glycine, and 1 mg / mL glutathione.

[0059] The preparation method consists of the following steps:

[0060] Step 1: Prepare 0.9% phosphate buffer solution to obtain solution A.

[0061] Step 2: Divide solution A into two parts. Dissolve arginine, glycine, glutathione, recombinant collagen, and recombinant elastin in one part of solution A to obtain solution B.

[0062] Step 3: Dissolve non-crosslinked sodium hyaluronate and hyaluronic acid microspheres in another portion of solution A to obtain solution C.

[0063] Step 4: Mix solution B and solution C and stir well to obtain solution D.

[0064] Step 5: After sterilization, solution D is filled into vials to obtain the injectable composite solution.

[0065] Example 4

[0066] This embodiment provides an injectable composite solution containing 12 mg / mL non-crosslinked sodium hyaluronate, 20 mg / mL hyaluronic acid microspheres, 1 mg / mL recombinant collagen, 1 mg / mL recombinant elastin, 0.5 mg / mL arginine, 0.5 mg / mL glycine, and 1 mg / mL mannitol.

[0067] The preparation method is the same as in Example 2.

[0068] Comparative Example 1

[0069] This comparative example provides an injectable compound solution containing 20 mg / mL hyaluronic acid microspheres, 0.5 mg / mL arginine, 0.5 mg / mL glycine, and 1 mg / mL mannitol.

[0070] The preparation method consists of the following steps:

[0071] Step 1: Prepare 0.9% phosphate buffer solution to obtain solution A.

[0072] Step 2: Divide solution A into two parts. Dissolve arginine, glycine, and mannitol in one part of solution A to obtain solution B.

[0073] Step 3: Dissolve the hyaluronic acid microspheres in another part of solution A to obtain solution C.

[0074] Step 4: Mix solution B and solution C and stir well to obtain solution D.

[0075] Step 5: After sterilization, solution D is filled into vials to obtain the injectable composite solution.

[0076] Comparative Example 2

[0077] This comparative example provides an injectable compound solution containing 12 mg / mL non-crosslinked sodium hyaluronate, 0.5 mg / mL arginine, 0.5 mg / mL glycine, and 1 mg / mL mannitol.

[0078] The preparation method consists of the following steps:

[0079] Step 1: Prepare 0.9% phosphate buffer solution to obtain solution A.

[0080] Step 2: Divide solution A into two parts. Dissolve arginine, glycine, and mannitol in one part of solution A to obtain solution B.

[0081] Step 3: Dissolve non-crosslinked sodium hyaluronate in another portion of solution A to obtain solution C.

[0082] Step 4: Mix solution B and solution C and stir well to obtain solution D.

[0083] Step 5: After sterilization, solution D is filled into vials to obtain the injectable composite solution.

[0084] Comparative Example 3

[0085] This comparative example provides an injectable composite solution containing 12 mg / mL hyaluronic acid microspheres, 8 mg / mL non-crosslinked sodium hyaluronate, 0.5 mg / mL arginine, 0.5 mg / mL glycine, and 1 mg / mL mannitol.

[0086] The preparation method consists of the following steps:

[0087] Step 1: Prepare 0.9% phosphate buffer solution to obtain solution A.

[0088] Step 2: Divide solution A into two parts. Dissolve arginine, glycine, and mannitol in one part of solution A to obtain solution B.

[0089] Step 3: Dissolve non-crosslinked sodium hyaluronate and hyaluronic acid microspheres in another portion of solution A to obtain solution C.

[0090] Step 4: Mix solution B and solution C and stir well to obtain solution D.

[0091] Step 5: After sterilization, solution D is filled into vials to obtain the injectable composite solution.

[0092] Comparative Example 4

[0093] This comparative example provides an injectable compound solution containing 12 mg / mL hyaluronic acid microspheres, 2 mg / mL non-crosslinked sodium hyaluronate, 4 mg / mL recombinant collagen, 4 mg / mL recombinant elastin, 0.5 mg / mL arginine, 0.5 mg / mL glycine, and 1 mg / mL mannitol.

[0094] The preparation method consists of the following steps:

[0095] Step 1: Prepare 0.9% phosphate buffer solution to obtain solution A.

[0096] Step 2: Divide solution A into two parts. Dissolve arginine, glycine, mannitol, recombinant collagen, and recombinant elastin in a portion of solution A to obtain solution B.

[0097] Step 3: Dissolve non-crosslinked sodium hyaluronate and hyaluronic acid microspheres in another portion of solution A to obtain solution C.

[0098] Step 4: Mix solution B and solution C and stir well to obtain solution D.

[0099] Step 5: After sterilization, solution D is filled into vials to obtain the injectable composite solution.

[0100] Comparative Example 5

[0101] This comparative example provides an injectable compound solution containing 8 mg / mL non-crosslinked sodium hyaluronate, 12 mg / mL hyaluronic acid microspheres, 1 mg / mL recombinant collagen, 1 mg / mL recombinant elastin, 0.5 mg / mL arginine, 0.5 mg / mL glycine, and 1 mg / mL mannitol.

[0102] The preparation method consists of the following steps:

[0103] Step 1: Prepare 0.9% phosphate buffer solution to obtain solution A.

[0104] Step 2: Dissolve arginine, glycine, mannitol, recombinant collagen, recombinant elastin, non-crosslinked sodium hyaluronate, and hyaluronic acid microspheres in solution A to obtain solution B.

[0105] Step 3: After sterilization, solution B is filled into vials to obtain the injectable composite solution.

[0106] Experiment Example 1: Transmittance Verification

[0107] The transmittance of the samples prepared in the above examples and comparative examples was measured at 530 nm, and the transmittance of 0.45% PBS solution at 530 nm was 100%.

[0108] Experimental method: Accurately measure 0.20 mL of each sample into a 96-well plate using a pipette, and measure the absorbance at 530 nm using an ELISA reader.

[0109] Transmittance calculation results:

[0110] T=10 -A ×100%

[0111] Where: T—transmittance

[0112] A—Measured absorbance value

[0113] Table 1. Results of sample transmittance test

[0114] sample Light transmittance (unit: %) Example 1 4.38 Example 2 4.47 Example 3 6.20 Example 4 2.06 Comparative Example 1 1.89 Comparative Example 2 99.20 Comparative Example 3 4.12 Comparative Example 4 3.88 0.45% PBS 100

[0115] The data above shows that the light transmittance of the product is mainly affected by the hyaluronic acid microspheres. The higher the concentration of microspheres, the lower the light transmittance. Furthermore, the microsphere ratio range provided in the embodiments of this invention can basically ensure the opacity of the composite solution, so as to avoid the Tyndall effect when used for facial injection.

[0116] Experiment Example 2: Verification of Hyaluronic Acid Degradation Rate

[0117] Take the experimental sample into a vial, add 0.5 mol / L sulfuric acid solution and heat until completely dissolved. Add 1 mol / L sodium hydroxide to neutralize, then dilute with water. Mix well and take 1 ml of the solution into a test tube for later use.

[0118] Take the experimental sample into a vial, add 1 U / ml of BTH (bovine testicular hyaluronidase) solution, and place it in a 37℃, 120 rpm constant temperature water bath shaker for reaction. Remove the sample after a set time, then boil it to inactivate the enzyme. Transfer the sample to a 20 mL volumetric flask and make up to volume. Centrifuge at 10000 rpm and 4℃ for 20 min. After centrifugation, take 1 mL of the supernatant into a stoppered test tube for later use.

[0119] The absorbance of sodium hyaluronate in acid-hydrolyzed and enzymatically hydrolyzed samples was measured using the sulfuric acid-carbazole method. The degradation rate was then determined by comparing the content of the acid-hydrolyzed sample with the total content at different time points.

[0120] Table 2 Results of Hyaluronic Acid Degradation Rate Test in Samples

[0121] sample Degradation rate (unit: %) Example 1 85.68％ Example 2 76.92％ Example 3 90.15％ Comparative Example 2 112.21％ Comparative Example 3 84.43％

[0122] The data above shows that uncrosslinked hyaluronic acid solution degrades rapidly, while hyaluronic acid microspheres exhibit significantly better degradation performance than hyaluronic acid solution. Furthermore, the anti-enzymatic properties of the product are further enhanced by the addition of elastin, collagen, and hyaluronidase inhibitors.

[0123] Experiment Example 3: Verification of the homogeneity and stability of the composite solution

[0124] Referring to YY / T 0681.1-2018 "Test Methods for Sterile Medical Device Packaging Part 1: Guidelines for Accelerated Aging Tests" and "Guiding Principles for Registration Application Materials on Shelf Life of Passive Implantable Medical Devices (2017 Revised Edition)," the products prepared in the above comparative examples and embodiments were placed in a stability test chamber. The temperature was adjusted to 40℃±2℃ and the relative humidity to 75%±5%. Samples were taken after 1, 2, 4, 8, 16, and 24 weeks under these conditions. The appearance and light transmittance were then comprehensively evaluated. Based on the evaluation results, the solution homogeneity was graded from 0 to 3. Grade 0 represents virtually no change in solution homogeneity; Grade 1 represents the solution beginning to become heterogeneous, but without visible stratification; Grade 2 represents the solution beginning to show stratification; and Grade 3 represents complete stratification. Figure 3 As shown, the left side displays an image of the product from Example 2 after 24 weeks of storage, and the right side displays an image of the product from Comparative Example 1 after 24 weeks of storage. The experimental results are as follows:

[0125] Table 3. Results of sample homogeneity stability test

[0126]

[0127]

[0128] The data above shows that the proportions of each component provided in the embodiments of the present invention can ensure the uniform dispersion of hyaluronic acid microspheres in hyaluronic acid solution. The appropriate addition of elastin and collagen can cause entanglement between them and the hyaluronic acid chains, strengthen the network force of the hyaluronic acid solution, improve the stability of the system, and ensure the overall uniformity and stability of the composite solution.

[0129] It should be understood that the disclosed invention is not limited to the specific methods, schemes, and substances described, as these are all subject to variation. It should also be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the scope of the invention, which is limited only by the appended claims.

[0130] Those skilled in the art will also recognize, or be able to identify, many equivalents of the specific embodiments of the invention described herein using no more than conventional experiments. These equivalents are also included in the appended claims.

Claims

1. An injectable compound solution, characterized in that, By weight, the injectable compound solution comprises 5-20 parts of hyaluronic acid microspheres, 5-12 parts of non-crosslinked sodium hyaluronate, 0.1-3 parts of collagen, and 0.1-3 parts of elastin; The preparation method of the injection compound solution includes the following steps: (1) Dissolve collagen and elastin in buffer solution to obtain solution A; (2) Dissolve hyaluronic acid microspheres and non-crosslinked sodium hyaluronate in buffer solution to obtain solution B; (3) Mix solution A and solution B to obtain solution C; (4) Solution C is sterilized and then filled into the injection compound solution to obtain the injection compound solution.

2. The injectable compound solution according to claim 1, characterized in that, The injectable compound also contains a hyaluronidase inhibitor.

3. The injectable composite solution according to claim 2, characterized in that, The hyaluronidase inhibitor is 0.5-1.5 parts by weight.

4. The injectable compound solution according to any one of claims 1-3, characterized in that, The injectable compound also contains other functional ingredients, including antioxidants.

5. The injectable compound solution according to claim 4, characterized in that, The antioxidant is 0.1-3 parts by weight.

6. The injectable compound solution according to claim 4, characterized in that, The antioxidant is selected from one or more of glutathione, mannitol, vitamin C, resveratrol, citric acid, and sorbitol.

7. The injectable compound solution according to claim 1, characterized in that, Step (1) further includes dissolving hyaluronidase inhibitors and / or other functional ingredients in a buffer solution; the functional ingredients include antioxidants.

8. The injectable compound solution according to claim 1 or 7, characterized in that, The buffer solution is a phosphate buffer.

9. The application of the injectable compound solution according to claim 1 in the preparation of products injected into the dermal layer of the skin.

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