Porous hollow glass bead capable of slowly releasing collagen and application of porous hollow glass bead

Abstract

The invention relates to the technical field of medical cosmetology, in particular to a porous hollow glass bead capable of slowly releasing collagen and application of the porous hollow glass bead. The porous hollow glass bead capable of slowly releasing the collagen comprises a porous hollow glass bead body, the outer wall of the porous hollow glass bead body is provided with a pore channel structure penetrating through the exterior and an inner cavity of the hollow glass bead body, and the pore channel and the inner cavity of the porous hollow glass bead body are filled with collagen gel. The compressive strength of the hollow glass beads is utilized to improve the mechanical supporting effect, the collagen gel is subjected to catalytic decomposition under the action of collagenase in a body so as to achieve the slow-release effect, the outer walls of the hollow glass beads slow down the reaction time through physical isolation, and then the slow-release time is prolonged; meanwhile, ions such as Si and Ca released by the hollow glass beads can promote cells to secrete collagen, the biological activity is improved, and the three beneficial effects of physical support, collagen slow release and biological safety are achieved.

Description

Technical Field

[0001] This invention relates to the field of medical aesthetics technology, specifically to a porous hollow glass microsphere capable of slow-release collagen and its applications. Background Technology

[0002] With the accelerating aging of society and the increasing pursuit of a youthful appearance, the facial minimally invasive cosmetic surgery market is experiencing explosive growth. Injectable facial filler techniques, due to their advantages such as ease of operation, minimal invasiveness, safety, reliability, short recovery period, and immediate results, have become one of the preferred cosmetic procedures. The human face is a complex layered structure, and facial aging is mainly manifested in changes in soft tissue structure and a reduction in volume, such as thinning skin, wrinkle formation, and decreased elasticity. Ideal facial rejuvenation filler materials should possess good biocompatibility, controllable durability, and a high degree of safety.

[0003] Currently, filler materials on the market can be divided into several categories based on their mechanism of action and composition, but each has significant limitations: One category mainly consists of hydrogels such as hyaluronic acid and collagen. Collagen, as a natural extracellular matrix component, has excellent biocompatibility; however, pure collagen fillers degrade rapidly in vivo, lack mechanical strength and structural stability, resulting in poor support and short-lasting effects, requiring multiple injections in a short period to achieve the desired support. To overcome the limitations of single-material fillers, synthetic microsphere composite fillers that can induce collagen and fiber production have gradually developed and captured a portion of the market. These include PMMA microspheres, PCL microspheres, and hydroxyapatite microspheres. These microspheres can remain at the injection site for a long time after being injected subcutaneously, providing physical support and stimulating fibroblasts to secrete collagen, thereby achieving autologous collagen secretion and a long-lasting filling effect. However, it should be noted that although these materials have excellent biological activity, there are still some cases that show that these materials can cause sensitization, redness and swelling. Moreover, these microspheres are extremely small in size and degrade very slowly. Once they trigger an immune response and cause side effects, surgical removal is extremely difficult.

[0004] Chinese patent application CN118286099A, published on July 5, 2024, discloses a collagen-loaded polymer microsphere, an injection filler containing the microsphere, and a preparation method. The method involves dropwise addition of an organic phase formed by polymer material and a porogen in a solvent to an aqueous phase of a surfactant solution to obtain an O / W emulsion. Heating in a water bath causes the polymer to coagulate and precipitate, simultaneously dissolving the porogen, resulting in hollow, porous polymer emulsion particles. These hollow, porous polymer emulsion particles are then added to a collagen aqueous solution. Under the action of a catalyst, the carboxyl and hydroxyl groups on the surface of the polymer microspheres undergo dehydration condensation with the carboxyl and polyphenolic hydroxyl groups in the collagen to form ester bonds. Through esterification, collagen is stably loaded into the hollow, porous polymer microspheres, yielding the collagen-loaded polymer microsphere product. This product is then combined with a gel carrier (sodium hyaluronate, carboxymethyl cellulose, polydeoxyribonucleotides, and polynucleotides) to form an injection filler. Polymer microspheres have a hollow, porous structure with advantages such as large specific surface area and low density, allowing them to load more collagen in the same volume. The filler has good biocompatibility, biodegradability, and excellent sustained-release filling ability. As the gel carrier is absorbed and metabolized, the polymer microspheres are recognized by the human body as foreign bodies, triggering an inflammatory response. The slightly acidic environment caused by inflammation breaks the ester bonds between collagen and polymer microspheres, releasing collagen. At the same time, the microspheres stimulate the growth of autologous collagen, achieving a better sustained-release effect and a more lasting effect, making the filling effect more natural and longer-lasting.

[0005] However, the aforementioned injectable fillers containing collagen-loaded polymer microspheres still have drawbacks such as poor physical support, low collagen loading rate, and poor sustained-release effect. Furthermore, their polymer microspheres have a slow degradation rate and can trigger inflammatory reactions, posing safety risks. Summary of the Invention

[0006] The purpose of this invention is to provide a porous hollow glass microsphere that can slowly release collagen, solving the problems of poor physical support and poor slow-release effect of existing fillers.

[0007] The second objective of this invention is to provide an application of porous hollow glass microspheres capable of sustained-release collagen in injectable tissue fillers, thereby solving the problems of poor physical support and poor sustained-release effect of existing fillers.

[0008] To solve the above-mentioned technical problems, the technical solution of the porous hollow glass microspheres capable of slow-release collagen in this invention is as follows: A porous hollow glass microsphere capable of slow-release collagen includes porous hollow glass microspheres, wherein the outer wall of the porous hollow glass microspheres has a channel structure that connects the outside and the inner cavity of the hollow glass microspheres, and the channels and the inner cavity of the porous hollow glass microspheres are filled with collagen gel.

[0009] This invention improves upon existing technology by providing porous hollow glass microspheres capable of slow-release collagen, which have the following technical advantages: 1) Mechanical support effect: Gels such as collagen and hyaluronic acid have poor self-support effect and cannot provide good support for skin tissue to smooth wrinkles; while hollow glass microspheres have better compressive strength. Using them as a support material for injectable tissue fillers can greatly increase their mechanical support effect, thereby improving their filling effect on skin folds; similarly, their spherical structure avoids mechanical damage to cells caused by irregular particles, and after being implanted in the body, the spherical structure can stimulate cells to secrete collagen, thereby enhancing their biological activity.

[0010] 2) Collagen is a commonly used filler with good bioactivity and biosafety. However, collagenase in the body can quickly break down the implanted collagen gel, causing its support effect to decrease rapidly over time, requiring patients to have multiple injections to maintain the support effect. The outer wall of hollow glass microspheres (HGM) can reduce the contact area between enzymes and collagen gel through physical isolation, thereby slowing down the reaction time and allowing collagen to be released for a longer period of time, thus enhancing its long-lasting activity.

[0011] 3) The porous hollow glass microspheres themselves are composed of borosilicate glass. The Si and Ca ions released by them can promote collagen secretion by cells, promote cell regeneration and repair, and enhance the biological activity of the material. In addition, their thin walls greatly reduce the inorganic content, accelerate their degradation time, and prevent them from existing in the body for a long time (more than one year), thus avoiding the risk of immunogenicity caused by long-term presence in the body and reducing the risks borne by patients. In summary, the hollow glass microspheres@crosslinked collagen gel provided by this invention can achieve three beneficial effects: physical support, sustained release of collagen, and biocompatibility.

[0012] To further enhance collagen production and degradation capacity, the porous hollow glass microspheres preferably have a particle size D50 of 20-75 μm and an outer wall thickness of 1-2 μm. Microspheres with excessively small particle sizes may enter blood vessels, while those with excessively large particle sizes may cause a granular feel, affecting the appearance and feel of the patient's skin. Furthermore, hollow glass microspheres of this size, after implantation, can stimulate cells to express collagen-related genes, promoting the generation of new collagen.

[0013] To further improve the preparation efficiency of porous hollow glass microspheres capable of sustained-release collagen, preferably, the preparation method of porous hollow glass microspheres capable of sustained-release collagen includes the following steps: (1) Hollow glass microspheres are etched in hydrofluoric acid solution to make the outer wall have a channel structure that connects the outside and the inner cavity of the hollow glass microspheres, so as to obtain porous hollow glass microspheres. (2) The porous hollow glass microspheres are immersed in a collagen solution under ice bath conditions, so that the collagen solution enters the inner cavity of the hollow glass microspheres from the pore structure. Then, the collagen solution is reacted at 36~38℃ to form a collagen gel through self-crosslinking, thus obtaining porous hollow glass microspheres that can release collagen slowly.

[0014] In order to further control the size of the pore structure, preferably, in step (1), the volume of hydrofluoric acid solution corresponding to each 3~5g hollow glass microspheres is 100~120mL and the concentration is 1~2%; the etching time is 20~40min.

[0015] To further improve the retention time of the filling material, preferably, in step (2), 20-30 mL of collagen solution with a concentration of 3-5 mg / mL is added for every 2-3 g of porous hollow glass microspheres, and the number average molecular weight of the collagen is 20,000-50,000 Da.

[0016] To further increase the collagen loading, preferably, in step (2), the impregnation is vacuum impregnation for 60-90 minutes. Uncrosslinked collagen penetrates into the porous hollow glass microspheres under vacuum. After crosslinking, it changes from a liquid to a semi-solid state and cannot flow out of the pores of the hollow glass microspheres. Essentially, it is a physical confinement effect.

[0017] To further improve the stability of the loaded collagen, preferably, the reaction time in step (2) is 1-2 hours.

[0018] The technical solution for the application of porous hollow glass microspheres with sustained-release collagen in injectable tissue fillers according to the present invention is as follows: The application of porous hollow glass microspheres capable of sustained-release collagen in injectable tissue fillers, the injectable tissue fillers comprising a gel carrier and the porous hollow glass microspheres capable of sustained-release collagen.

[0019] The application of porous hollow glass microspheres with sustained-release collagen provided by this invention in injectable tissue fillers allows the injectable tissue filler to be injected into the body. The gel carrier is first absorbed and metabolized, and the collagenase in the body enters the hollow glass microspheres through the pore structure, catalyzing the decomposition of cross-linked collagen gel into small molecules, which can then be released from the pore structure. The shell formed by the hollow glass microspheres can delay the release process, thereby extending its duration of action.

[0020] To further improve injectability and support, preferably, the porous hollow glass microspheres capable of slow-release collagen account for no more than 20% of the injectable tissue filler by mass. This content avoids a sudden increase in extrusion force due to excessive solid microsphere content, which would reduce injectability, and also avoids poor support due to insufficient solid microsphere content.

[0021] To further improve the filling effect, preferably, the gel carrier is a cross-linked hyaluronic acid gel with a cross-linking degree of 20-40%. Attached Figure Description

[0022] Figure 1 This is an optical microscope image of the porous hollow glass microspheres that can release collagen in Embodiment 1 of the present invention. Figure 2 This is a SEM image of the porous hollow glass microspheres of Embodiment 1 of the present invention; Figure 3 This is a SEM image of the porous hollow glass microspheres capable of slow-release collagen according to Example 1 of the present invention. Figure 4 An optical photograph of the injectable tissue filler of Embodiment 5 of the present invention; Figure 5 The results are from the injection force test of injectable tissue fillers; Figure 6 The results are for the storage modulus test of injectable tissue fillers; Figure 7 The results are the loss modulus test results for injectable tissue fillers; Figure 8 The test results show the composite viscosity of injectable tissue fillers; Figure 9 The graph shows the collagen release rate test results of HGM@COL microspheres from Examples 1-4 and collagen gel particles obtained from Comparative Example 1. Figure 10 This is a photograph of the injectable tissue filler of Example 5 of the present invention injected under the skin of a mouse. Detailed Implementation

[0023] The technical concept of the porous hollow glass microspheres capable of sustained-release collagen provided by this invention is as follows: Currently, stimulating synthetic microspheres such as PMMA and PCL microspheres can provide physical support and stimulate fibroblasts to secrete collagen. However, they have slow degradation rates, are prone to triggering immune responses, are difficult to remove surgically, lack collagen loading, and have short durations of effect. Existing technologies have developed hollow porous polymer emulsion particles that can load collagen. After implantation, as the gel carrier is absorbed and metabolized, the foreign body inflammatory response causes collagen to detach from the polymer particles and begin to be released, achieving a sustained-release effect and extending the duration of effect. However, the filler formed by these polymer emulsion particles and the gel carrier has poor support, inflammatory responses can easily lead to safety risks, and the collagen loading is still low. The chemical bonds of collagen result in low sustained-release efficiency and short duration of effect. In addition, the polymer microspheres have slow degradation rates, leading to side effects and high surgical difficulty.

[0024] The porous hollow glass microspheres for sustained-release collagen provided by this invention utilize the compressive strength of the hollow glass microspheres to improve mechanical support. The collagen gel is catalytically decomposed by collagenase in vivo, thereby achieving a sustained-release effect. The outer wall of the hollow glass microspheres slows down the reaction time through physical isolation, thus prolonging the sustained-release time. At the same time, the Si and Ca ions released by the hollow glass microspheres can promote the secretion of collagen by cells and improve biological activity, achieving three beneficial effects: physical support, sustained release of collagen, and biological safety.

[0025] The porous hollow glass microspheres that can release collagen provided by the present invention include porous hollow glass microspheres, wherein the outer wall of the porous hollow glass microspheres has a channel structure that connects the outside and the inner cavity of the hollow glass microspheres, and the channels and the inner cavity of the porous hollow glass microspheres are filled with collagen gel.

[0026] Specifically, the porous hollow glass microspheres have a particle size D50 of 20~75μm, a wall thickness of 1~2μm, and a pore structure diameter of 0.5~3μm. The hollow glass microspheres can be selected from HL-20, HL-25, HL-15, etc., produced by Zhengzhou Shenglete Hollow Microsphere New Material Co., Ltd.

[0027] The method for preparing porous hollow glass microspheres capable of sustained-release collagen provided by the present invention includes the following steps: (1) Etching: Hollow glass microspheres are etched in hydrofluoric acid solution to make the outer wall have a channel structure that connects the outside and the inner cavity of the hollow glass microspheres, thus obtaining porous hollow glass microspheres.

[0028] In step (1), the volume of hydrofluoric acid solution corresponding to each 3-5g hollow glass microspheres is 100-120mL and the concentration is 1-2%; the etching time is 20-40min. More preferably, the etching time is 20-30min.

[0029] It should be noted that hollow glass microspheres are relatively light and easily float on the surface of hydrofluoric acid solution. Therefore, during etching, they need to be sealed in a closed container filled with hydrofluoric acid solution. Preferably, the etching process is carried out on a shaker with a rotation speed of 200-500 rpm.

[0030] In step (1), after etching, porous hollow glass microspheres are obtained by washing and drying. The washing is carried out by washing with alkaline solution and water in sequence; the alkaline solution is selected from one or both of sodium hydroxide solution with a concentration of 1~5% and ammonia water; the drying temperature is 60~80℃ and the drying time is 2~8h.

[0031] It should be noted that after washing and drying, the hollow glass microspheres that do not have a through-hole structure are removed. The removal method is as follows: place the hollow glass microspheres that have been etched, washed and dried in water and let them stand for 30 to 60 minutes. Discard the floating matter on the upper layer. After the bottom sediment dries, the porous hollow glass microspheres with a through-hole structure on the outer wall are obtained.

[0032] (2) Impregnation-crosslinking: The porous hollow glass microspheres are impregnated in a collagen solution under ice bath conditions, so that the collagen solution enters the inner cavity of the hollow glass microspheres from the pore structure. Then, the collagen solution is reacted at 36~38℃ to form a collagen gel through self-crosslinking, thus obtaining porous hollow glass microspheres that can release collagen slowly.

[0033] In step (2), 20-30 mL of collagen solution with a concentration of 3-5 mg / mL is added for every 2-3 g of porous hollow glass microspheres. The number average molecular weight of the collagen is 20,000-50,000 Da.

[0034] In step (2), the impregnation is vacuum impregnation, and the vacuum impregnation time is 60~90min.

[0035] In step (2), the reaction time is 1 to 2 hours.

[0036] This invention relates to the application of porous hollow glass microspheres containing sustained-release collagen in injectable tissue fillers. The injectable tissue filler comprises a gel carrier and the aforementioned porous hollow glass microspheres containing sustained-release collagen. The porous hollow glass microspheres containing sustained-release collagen constitute no more than 20% of the injectable tissue filler by mass. Preferably, the porous hollow glass microspheres containing sustained-release collagen constitute 3-10% of the injectable tissue filler by mass.

[0037] The method for preparing the injectable tissue filler provided by this invention includes the following steps: mixing porous hollow glass microspheres capable of sustained-release collagen with a gel carrier. The gel carrier is a cross-linked hyaluronic acid gel with a cross-linking degree of 20-40%.

[0038] It should be noted that cross-linked hyaluronic acid gel is obtained by mixing cross-linked hyaluronic acid and phosphate buffer solution; the concentration of cross-linked hyaluronic acid gel is 2~5%.

[0039] This invention provides a method for preparing porous hollow glass microspheres capable of sustained-release collagen. Uncrosslinked collagen is infiltrated into the interior of the porous hollow glass microspheres. After crosslinking at physiological human temperatures, it changes from a liquid to a semi-solid state, preventing it from flowing out of the pores of the hollow glass microspheres. Essentially, this provides physical confinement. The sustained-release mechanism involves collagenase in the body entering the inner cavity of the hollow glass microspheres through the porous structure of the outer wall, catalyzing the decomposition of the crosslinked collagen gel, causing it to break down into smaller molecules that flow out through the pores. The physical action of the collagen results in high sustained-release efficiency, while the outer shell formed by the hollow glass microspheres further delays the release process, thus extending its duration of action. Simultaneously, the Si and Ca ions released by the hollow glass microspheres can promote collagen secretion by cells, enhancing biological activity. The thin wall of the outer shell reduces the inorganic content, accelerates degradation, and provides a certain degree of compressive strength, offering support. This method balances physical support, sustained collagen release, and biological safety.

[0040] The embodiments of the present invention will be further described below with reference to specific examples. Unless otherwise specified, the chemical reagents involved in the following examples are all commercially available conventional products.

[0041] I. Specific embodiments of the porous hollow glass microspheres for sustained-release collagen of the present invention Example 1 The porous hollow glass microspheres that can release collagen in this embodiment include porous hollow glass microspheres. The outer wall of the porous hollow glass microspheres has a channel structure that connects the outside and the inner cavity of the hollow glass microspheres. The channels and the inner cavity of the porous hollow glass microspheres are filled with collagen gel.

[0042] The method for preparing porous hollow glass microspheres capable of sustained-release collagen in this embodiment is as follows: (1) Place 3g of hollow glass microspheres HGM in a 200mL plastic bottle, add 100mL of 2% hydrofluoric acid solution, seal the bottle, and place it on a shaker at a speed of 200rpm for 20min. Then, place the resulting mixture in a Buchner funnel, filter it, and wash it with 1% NaOH solution and deionized water, washing at least 3 times each time. After that, place it in a 60℃ oven and dry it for 4h. Then, gently place the obtained hollow glass microspheres in deionized water, stir slowly, and let it stand for 30min. Discard the upper floating matter that has not formed a pore structure. After the bottom precipitate dries, it becomes a porous hollow glass microsphere with a through-hole structure on the outer wall. (2) Collagen (number average molecular weight of 50000 Da) was added to water to obtain a collagen solution with a concentration of 3 mg / mL. 20 mL of the collagen solution with a concentration of 3 mg / mL was placed on an ice surface and 2 g of the porous hollow glass microspheres with a through-pore structure obtained in step (1) was placed on the ice surface. After sinking to the bottom, the microspheres were placed in a vacuum drying oven and vacuumed. The microspheres were vacuum-impregnated at the temperature of an ice bath for 1 h, so that the collagen solution could enter the inner cavity of the hollow glass microspheres through the through-pore structure. The hollow glass microspheres were removed by filtration, rinsed with deionized water, and placed in a 37°C oven for 1 h to react, so that the internal collagen solution could self-crosslink to form a collagen gel, thus obtaining HGM@COL microspheres, which are the porous hollow glass microspheres with sustained-release collagen provided by this invention.

[0043] Example 2 The porous hollow glass microspheres that can release collagen in this embodiment include porous hollow glass microspheres. The outer wall of the porous hollow glass microspheres has a channel structure that connects the outside and the inner cavity of the hollow glass microspheres. The channels and the inner cavity of the porous hollow glass microspheres are filled with collagen gel.

[0044] The method for preparing porous hollow glass microspheres capable of sustained-release collagen in this embodiment is as follows: (1) Same as step (1) in Example 1.

[0045] (2) Collagen (number average molecular weight of 28600 Da) was added to water to obtain a collagen solution with a concentration of 3 mg / mL. 20 mL of the collagen solution with a concentration of 3 mg / mL was placed on an ice surface and 2 g of the porous hollow glass microspheres with a through-pore structure obtained in step (1) was placed on the ice surface. After sinking to the bottom, the microspheres were placed in a vacuum drying oven and vacuumed. The microspheres were vacuum-impregnated at the temperature of an ice bath for 1 h, so that the collagen solution could enter the inner cavity of the hollow glass microspheres through the through-pore structure. The hollow glass microspheres were removed by filtration, rinsed with deionized water, and placed in a 37°C oven for 1 h to react, so that the internal collagen solution could self-crosslink to form a collagen gel, thus obtaining HGM@COL microspheres, which are the porous hollow glass microspheres with sustained-release collagen provided by the present invention.

[0046] Example 3 The porous hollow glass microspheres that can release collagen in this embodiment include porous hollow glass microspheres. The outer wall of the porous hollow glass microspheres has a channel structure that connects the outside and the inner cavity of the hollow glass microspheres. The channels and the inner cavity of the porous hollow glass microspheres are filled with collagen gel.

[0047] The method for preparing porous hollow glass microspheres capable of sustained-release collagen in this embodiment is as follows: (1) Same as step (1) in Example 1.

[0048] (2) Collagen (number average molecular weight of 50000 Da) was added to water to obtain a collagen solution with a concentration of 5 mg / mL. 20 mL of collagen solution with a concentration of 3 mg / mL was placed on ice and 2 g of porous hollow glass microspheres with a through-pore structure obtained in step (1) was placed on the ice. After sinking to the bottom, the microspheres were placed in a vacuum drying oven and vacuumed. They were vacuum-impregnated at the temperature of an ice bath for 1 h, so that the collagen solution could enter the inner cavity of the hollow glass microspheres through the through-pore structure. The hollow glass microspheres were removed by filtration, rinsed with deionized water, and placed in a 37°C oven for 1 h to react, so that the internal collagen solution could self-crosslink to form a collagen gel, thus obtaining HGM@COL microspheres, which are the porous hollow glass microspheres with sustained-release collagen provided by this invention.

[0049] Example 4 The porous hollow glass microspheres that can release collagen in this embodiment include porous hollow glass microspheres. The outer wall of the porous hollow glass microspheres has a channel structure that connects the outside and the inner cavity of the hollow glass microspheres. The channels and the inner cavity of the porous hollow glass microspheres are filled with collagen gel.

[0050] The method for preparing porous hollow glass microspheres capable of sustained-release collagen in this embodiment is as follows: (1) Place 3g of hollow glass microspheres HGM in a 200mL plastic bottle, add 100mL of 1% hydrofluoric acid solution, seal the bottle, and place it on a shaker at a speed of 200rpm for 20min. Then, place the resulting mixture in a Buchner funnel, filter it, and wash it with 1% NaOH solution and deionized water, washing at least 3 times each time. After that, place it in a 60℃ oven and dry it for 4h. Then, gently place the obtained hollow glass microspheres in deionized water, stir slowly, let it stand for 30min, discard the upper floating matter that has not formed a pore structure, and dry the bottom precipitate to obtain porous hollow glass microspheres with a through-hole structure on the outer wall. (2) Same as step (2) in Example 1. HGM@COL microspheres are obtained, which are porous hollow glass microspheres that can release collagen in a sustained manner as provided by the present invention.

[0051] II. Specific Examples of the Application of the Porous Hollow Glass Microspheres of the Slow-Release Collagen of the Present Invention in Injectable Tissue Fillers Example 5 This embodiment describes the application of porous hollow glass microspheres capable of sustained-release collagen in injectable tissue fillers, which include cross-linked hyaluronic acid gel and porous hollow glass microspheres capable of sustained-release collagen obtained in Example 1.

[0052] The preparation method of the injectable tissue filler in this embodiment is as follows: Two g of porous hollow glass microspheres with sustained-release collagen obtained in Example 1 were added to 18 g of 2% cross-linked hyaluronic acid gel (obtained by mixing cross-linked hyaluronic acid and phosphate buffer solution, with a cross-linking degree of 30%). After mechanical stirring until homogeneous, the mixture was placed in a vacuum drying oven for degassing. The gel was then loaded into a 1 mL syringe and sterilized at 121°C to obtain HA-10HGM@COL tissue filler, which is the injectable tissue filler provided by this invention. In a solution containing collagenase, collagen monomers can be released through the porous structure on the surface of the glass microspheres, thereby increasing the collagen content in the body.

[0053] Example 6 This embodiment describes the application of porous hollow glass microspheres capable of sustained-release collagen in injectable tissue fillers, which include cross-linked hyaluronic acid gel and porous hollow glass microspheres capable of sustained-release collagen obtained in Example 1.

[0054] The preparation method of the injectable tissue filler in this embodiment is as follows: 1g of porous hollow glass microspheres with sustained-release collagen obtained in Example 1 were added to 19g of cross-linked hyaluronic acid gel with a concentration of 2%. After being mechanically stirred evenly, the mixture was placed in a vacuum drying oven for degassing. Then, it was loaded into a 1 mL syringe, placed in an autoclave, and sterilized at 121°C to obtain HA-5HGM@COL tissue filler, which is the injectable tissue filler provided by the present invention.

[0055] Example 7 This embodiment describes the application of porous hollow glass microspheres capable of sustained-release collagen in injectable tissue fillers, which include cross-linked hyaluronic acid gel and porous hollow glass microspheres capable of sustained-release collagen obtained in Example 1.

[0056] The preparation method of the injectable tissue filler in this embodiment is as follows: 0.6g of the porous hollow glass microspheres with sustained-release collagen obtained in Example 1 were added to 19.4g of cross-linked hyaluronic acid gel with a concentration of 2%. After mechanical stirring, the mixture was placed in a vacuum drying oven for degassing. Then, the mixture was loaded into a 1mL syringe and placed in an autoclave for sterilization at 121°C. Finally, HA-3HGM@COL tissue filler was obtained, which is the injectable tissue filler provided by the present invention.

[0057] Example 8 This embodiment describes the application of porous hollow glass microspheres capable of sustained-release collagen in injectable tissue fillers, which include cross-linked hyaluronic acid gel and porous hollow glass microspheres capable of sustained-release collagen obtained in Example 2.

[0058] The preparation method of the injectable tissue filler in this embodiment is as follows: Two g of the porous hollow glass microspheres with sustained-release collagen obtained in Example 2 were added to 18 g of 2% cross-linked hyaluronic acid gel. After mechanical stirring until homogeneous, the mixture was placed in a vacuum drying oven for degassing. The mixture was then loaded into a 1 mL syringe and sterilized at 121°C to obtain HA-10HGM@COL tissue filler, which is the injectable tissue filler provided by this invention. In a solution containing collagenase, collagen monomers can be released through the porous structure on the surface of the glass microspheres, thereby increasing the collagen content in the body.

[0059] Example 9 This embodiment describes the application of porous hollow glass microspheres capable of sustained-release collagen in injectable tissue fillers, which include cross-linked hyaluronic acid gel and porous hollow glass microspheres capable of sustained-release collagen obtained in Example 3.

[0060] The preparation method of the injectable tissue filler in this embodiment is as follows: Two g of the porous hollow glass microspheres with sustained-release collagen obtained in Example 3 were added to 18 g of 2% cross-linked hyaluronic acid gel. After mechanical stirring until homogeneous, the mixture was placed in a vacuum drying oven for degassing. The mixture was then loaded into a 1 mL syringe and sterilized at 121°C to obtain HA-10HGM@COL tissue filler, which is the injectable tissue filler provided by this invention. In a solution containing collagenase, collagen monomers can be released through the porous structure on the surface of the glass microspheres, thereby increasing the collagen content in the body.

[0061] Example 10 This embodiment describes the application of porous hollow glass microspheres capable of sustained-release collagen in injectable tissue fillers, which include cross-linked hyaluronic acid gel and porous hollow glass microspheres capable of sustained-release collagen obtained in Example 4.

[0062] The preparation method of the injectable tissue filler in this embodiment is as follows: Two g of the porous hollow glass microspheres with sustained-release collagen obtained in Example 4 were added to 18 g of 2% cross-linked hyaluronic acid gel. After mechanical stirring until homogeneous, the mixture was placed in a vacuum drying oven for degassing. The mixture was then loaded into a 1 mL syringe and sterilized at 121°C to obtain HA-10HGM@COL tissue filler, which is the injectable tissue filler provided by this invention. In a solution containing collagenase, collagen monomers can be released through the porous structure on the surface of the glass microspheres, thereby increasing the collagen content in the body.

[0063] III. Comparative Example Comparative Example 1 The injectable tissue fillers in this comparative example include cross-linked hyaluronic acid gel and collagen gel.

[0064] The preparation method of the injectable tissue filler in this comparative example is as follows: 20 mL of a collagen solution with a concentration of 3 mg / mL was placed in a 37°C oven and reacted for 1 hour to allow the collagen solution to self-crosslink and form a collagen gel. The gel was then passed through a 200-mesh sieve to obtain collagen gel particles, which were then mixed evenly with a 2% concentration of crosslinked hyaluronic acid gel. The weight ratio of the collagen gel was 10%, resulting in an injectable tissue filler.

[0065] IV. Experimental Examples The morphology of porous hollow glass microspheres capable of sustained-release collagen was observed. An optical microscope image of the porous hollow glass microspheres capable of sustained-release collagen from Example 1 is shown below. Figure 1 As shown, it exhibits a good spherical structure, indicating that it has a high degree of sphericity.

[0066] The SEM morphology image of the porous hollow glass microspheres obtained in step (1) of Example 1 is shown below. Figure 2 As shown, the outer wall of the hollow glass microspheres has a porous structure with a pore size of 1~3μm. The SEM morphology of the porous hollow glass microspheres that can slowly release collagen obtained in step (2) of Example 1 is shown below. Figure 3 As shown, collagen fills the interior of the microbeads, proving the feasibility of the method.

[0067] The morphology of the injectable tissue filler was observed. An optical photograph of the HA-10HGM@COL tissue filler from Example 5 is shown below. Figure 4 As shown, the cross-linked hyaluronic acid gel with added HGM@COL microspheres exhibits a white optical appearance.

[0068] The injection force of the injectable tissue fillers of Examples 5-7 and Comparative Example 1 was tested. These injectable tissue fillers have shear-refining properties and were injected through a 27G needle. The test results are as follows: Figure 5 As shown, the maximum injection force is less than 25N, proving that it can be injected manually.

[0069] The storage modulus and loss modulus of the injectable tissue fillers of Examples 5-7 and Comparative Example 1 were tested, and the test results are as follows: Figure 6-7As shown (horizontal axis represents frequency), in the range of 0.01~100Hz, the loss modulus of injectable tissue fillers is between 10~10000Pa, and the storage modulus is between 300~30000Pa. With the increase of the amount of porous hollow glass microspheres containing slow-release collagen, their modulus increases, and their storage modulus is greater than their loss modulus, exhibiting elastic solid behavior, which proves that they have a better supporting effect.

[0070] The composite viscosity of the injectable tissue fillers from Examples 5-7 and Comparative Example 1 was tested, and the test results are as follows: Figure 8 As shown (horizontal axis represents frequency), the composite viscosity of injectable tissue fillers ranges from 10 to 100,000 Pa•s in the range of 0.01 to 100 Hz. The composite viscosity increases with the increase of the amount of porous hollow glass microspheres containing sustained-release collagen. However, all groups retain the shear-thinning property, which is beneficial to their injectability.

[0071] The collagen sustained-release performance of the HGM@COL microspheres from Examples 1-4 and the collagen gel particles obtained from Comparative Example 1 was tested. The test methods and the collagen release rate calculation methods are as follows: Collagen release test: 10 mL of simulated body fluid was prepared into a 5 ng / mL solution with collagenase. 0.5 g of the product obtained in Examples 1-4 and Comparative Example 1 was immersed in the solution and placed in a shaker at 37°C with a shaking speed of 60 r / min. At regular time points, 2 mL of the supernatant was taken out, and 2 mL of the original solution was added simultaneously. After centrifugation, the collagen content in the solution was measured using the double urinary infusion method, and the total collagen release was determined according to the standard curve.

[0072] Total collagen loading: Take 0.5g of the product obtained in Examples 1-4 and Comparative Example 1, soak it in simulated body fluid with a collagenase concentration of 100ng / mL, take the supernatant every day until the total concentration does not change significantly, and determine it as the total loading.

[0073] Collagen release rate = Total collagen released / Total load * 100%.

[0074] The test results for collagen release rate are as follows: Figure 9 As shown, after 30 days of sustained release, the release rate of collagen gel particles reached 90%, while the release rate of HGM@COL microspheres was about 30%, demonstrating better sustained-release performance.

[0075] The HA-10HGM@COL tissue filler from Example 5 was injected subcutaneously into mice. A photograph of the actual product is shown below. Figure 10As shown in the image, the red circle indicates the injection site. It can be seen that the subcutaneous filler can provide physical support and smooth out skin wrinkles.

[0076] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A porous hollow glass microsphere capable of releasing collagen, characterized by comprising, The porous hollow glass microspheres comprise an outer wall having a pore structure penetrating the outer portion and the inner cavity of the hollow glass microspheres, and the pores and the inner cavity of the porous hollow glass microspheres are filled with collagen gel.

2. The slow-release collagen-hollow porous glass microsphere according to claim 1, wherein, The porous hollow glass microspheres have a particle size D50 of 20-75 μm, and the outer wall of the porous hollow glass microspheres has a wall thickness of 1-2 μm.

3. The slow-release collagen-hollow porous glass microsphere according to claim 1, wherein, The preparation method of the collagen-releasable porous hollow glass microspheres comprises the following steps: (1) etching the hollow glass microspheres in a hydrofluoric acid solution to make the outer wall have a pore structure penetrating the outer portion and the inner cavity of the hollow glass microspheres, thereby obtaining the porous hollow glass microspheres; (2) immersing the porous hollow glass microspheres in a collagen solution under ice-bath conditions, so that the collagen solution enters the inner cavity of the hollow glass microspheres from the pore structure, and then reacting at 36-38 ℃ to make the collagen solution self-crosslink to form collagen gel, thereby obtaining the collagen-releasable porous hollow glass microspheres.

4. The slow-release collagen-hollow porous glass microsphere according to claim 3, wherein, In step (1), 3-5 g of the hollow glass microspheres correspond to 100-120 mL of the hydrofluoric acid solution with a concentration of 1-2%, and the etching time is 20-40 min.

5. The slow-release collagen-hollow porous glass microsphere according to claim 3, wherein the collagen is collagen type I. In step (2), 2-3 g of the porous hollow glass microspheres correspond to 20-30 mL of the collagen solution with a concentration of 3-5 mg / mL, and the number-average molecular weight of the collagen is 20,000-50,000 Da.

6. The slow-release collagen-hollow porous glass microsphere according to claim 3, wherein the collagen is collagen type I. In step (2), the immersion is vacuum immersion, and the vacuum immersion time is 60-90 min.

7. The slow-release collagen-hollow porous glass microsphere according to claim 3, wherein the collagen is collagen type I. In step (2), the reaction time is 1-2 h.

8. Use of the collagen-releasable porous hollow glass microspheres according to any one of claims 1 to 7 in injectable tissue fillers, characterized in that, The injectable tissue filler comprises a gel carrier and the collagen-releasable porous hollow glass microspheres.

9. Use according to claim 8, wherein the compound is ###0002### The mass percentage of the collagen-releasable porous hollow glass microspheres in the injectable tissue filler is not more than 20%.

10. The use according to claim 8, wherein the compound is ###00003### or a pharmaceutically acceptable salt thereof. The gel carrier is a crosslinked hyaluronic acid gel with a crosslinking degree of 20-40%.

Images