CN111558083B

CN111558083B - Biodegradable injection filler, preparation method and application thereof

Info

Publication number: CN111558083B
Application number: CN202010398791.3A
Authority: CN
Inventors: 牛玉乐; 冯斌; 孙会谦; 王志军; 张景朋; 孙国涛; 范建国; 甄志彬; 邓声菊; 徐艳君; 王田园; 夏洋
Original assignee: Beijing Tianxinyuan Pharmaceutical Science And Technology Development Co ltd; Beijing Sihuan Pharmaceutical Co Ltd; Beijing Ao He Research Institute Co Ltd
Current assignee: Meiyan Space Biotechnology Jilin Co ltd; Meiyan Space Hebei Biotechnology Co ltd; Beijing Meiyan Space Biomedical Co Ltd
Priority date: 2020-01-14
Filing date: 2020-05-12
Publication date: 2021-11-12
Anticipated expiration: 2040-05-12
Also published as: CN111558083A; CN111150883A

Abstract

The invention provides a biodegradable polymer microparticle and a preparation method thereof, wherein the polymer microparticle is a copolymer of lactic acid and/or glycolic acid repeating units, and the particle size of the polymer microparticle is 10-150 μm. The PLLA particles have irregular, unsmooth or rough microscopic shapes, increase the contact area of the PLLA particles and cells, improve the adhesion capacity and residence time of the cells on a porous structure or a bracket structure, remarkably improve the cell affinity of the PLLA particles, and are beneficial to stimulating collagen cells to feel physical and mechanical microenvironment stimulation and make response reaction to the physical and mechanical microenvironment stimulation, thereby stimulating and accelerating the growth of collagen of organisms, removing wrinkles, beautifying, delaying senescence and having natural and lasting effects.

Description

Biodegradable injection filler, preparation method and application thereof

Technical Field

The invention relates to a biodegradable injection filling material, a preparation method and application thereof.

Background

Medical Cosmetology (Medical Cosmetology) refers to a cosmetic method for repairing and remodeling the appearance and shape of human body and parts of human body by using medicines, operations, Medical instruments and other Medical techniques with traumatism or irreversibility. With the technological progress and the continuous improvement of the living standard of people, people pay more attention to the quality of life problems such as facial wrinkles, aging delaying and the like. The report shows that the Chinese medical cosmetology market scale is continuously increased, the Chinese medical cosmetology market scale in 2018 reaches 2245 million yuan, which accounts for 10% of the global medical cosmetology market, and becomes the third market of the global medical cosmetology, and the worldwide medical cosmetology market scale is predicted to break through 3150 million yuan in 2020.

The injection filling beauty treatment is non-operation medical beauty treatment. The injection filling cosmetic method injects the filler into the local part of the human body to improve and modify the defects of facial soft tissues, static wrinkles of the skin, tissue contours and the like, has the advantages of convenient use, simple and convenient operation, small wound, quick recovery, aging delay, instant cosmetic effect and the like, and is widely applied to the fields of medical cosmetology, cosmetology dermatology, plastic surgery and the like.

The injectable filler includes absorbable injectable filler and non-absorbable injectable filler. Absorbable fillers include collagen, hyaluronic acid, and poly-L-lactic acid (PLLA), among others. PLLA is a synthetic biomedical polymer material marketed in Europe 1999 and approved by The FDA for The treatment of facial lipoatrophy in HIV patients and for injection filling of shallow to deep nasolabial folds and other facial wrinkles (Ferneini E, Boynton T, Almunajed H, et al.review of facial filters and injectable neuroxins [ J ]. The American Journal of Cosmetic Surgery,2013,30(2): 53-60.). PLLA can stimulate fibroblasts and other cells, and allow the patient to secrete collagen, thereby improving skin quality and filling up skin defects. Unlike other fillers, the effects after PLLA injection are naturally progressive, with therapeutic effects appearing weeks or months later, and lasting for up to three years in human tissues (Hamilton TK. skin augmentation and correction: the new generation of facial filters-A facial templates' S experience [ J ]. Clin Dermatol,2009,27(3): S13-S22.). Because PLLA has the advantages of long-acting property, biodegradability, absorption, high strength, good plasticity, no toxicity, no irritation, easy modification and the like, it is recognized as one of the most promising biomedical materials in the new century (Sheng Mingan, Zhang Jinhua, Li Yanhong. resource Development & Market,2007,23(11):1012-1014, 1028.).

Injectable fillers need to have good effectiveness and safety as well as good physical stability. However, PLLA still has technical problems that need to be improved urgently.

1. PLLA is hydrophobic and has poor adhesion to cells, which affects its filling effect. In order to promote the growth of skin collagen, the PLLA structure needs to be improved, firstly, a polymer scaffold containing a large number of porous structures is formed, so that the polymer scaffold has sufficient cell affinity and promotes the attachment of cells (collagen) on the polymer scaffold; secondly, a rough surface, a non-smooth surface or an irregular surface is formed, the stimulation of the surface to the physical and mechanical microenvironment of cells is increased, and the adhesion, migration, proliferation and differentiation of collagen cells are promoted (Fan Gua, Zhang Chun Mei, the application and research progress of polylactic acid in the medical field, science and technology guidance, 2010,28(19): 103-107).

2. Adverse reactions can be caused after PLLA injection, and potential safety hazards exist. PLLA is degraded in vivo into lactic acid to form an acidic microenvironment, which further causes red swelling, ecchymosis, bruise, edema, papule, visible nodules, periorbital nodules, injection region sclerosis, abscess, anaphylaxis, urticaria, skin hypertrophy and atrophy, angioedema, telangiectasia, skin sarcoidosis, scar, skin discoloration and other adverse reactions, and limits the application range of the PLLA.

3. The redispersibility of the lyophilized product after redissolving needs to be improved, and sedimentation and delamination are easy to occur, thereby causing inconvenient injection operation.

CN109010910A discloses a PLLA microsphere for injection, which takes sodium carboxymethylcellulose and mannitol as auxiliary materials, during the preparation process of the PLLA microsphere, the PLLA is dissolved in an organic solvent, and is uniformly mixed with an aqueous solution containing the sodium carboxymethylcellulose and the mannitol, then the organic solvent is removed, and the PLLA microsphere is obtained by freeze-drying. However, the technical scheme does not solve the problem of irritation caused by acidic degradation products of PLLA. And PLLA is a strong hydrophobic substance, and the powder injection is layered quickly after redissolving, so that the injection operation is inconvenient.

CN106492284B discloses a biodegradable filling material, which is prepared by mixing polydioxanone and poly-L-lactic acid according to the mass ratio of 7:3, and dissolving them in 1,1,2, 2-tetrachloroethane to prepare a high molecular organic solvent, and then dispersing hyaluronic acid with the average molecular weight of 20000 in the high molecular organic solvent. Hyaluronic acid is used as a synthetic material to be filled in the microsphere product, the freeze-dried powder injection is not uniformly dispersed after redissolving, and the smooth sphere is not beneficial to cell adhesion and growth, so that the injection filling effect is influenced.

CN100339057C discloses a biodegradable injectable implant comprising glycolic acid and particles consisting of a polymer comprising lactic acid repeating units, the polymer particles having a particle size of 20 μm to 120 μm, the implant employing PLGA microparticles instead of PLLA microparticles and being used in combination with hyaluronic acid. The hyaluronic acid applied to the implant in a large dose can aggravate injection stimulation and cause adverse reactions such as swelling, inflammation, anaphylactic reaction and the like.

CN104258470A discloses a polylactic acid microsphere and cross-linked hyaluronic acid mixed gel for injection, which consists of polylactic acid microspheres and cross-linked hyaluronic acid gel. But the dosage of hyaluronic acid in the mixed gel is larger, and the injection stimulation and adverse reaction are increased.

Therefore, how to develop a safer and more effective biodegradable injection filler to meet clinical needs becomes a technical problem which is urgently needed to overcome.

Disclosure of Invention

The invention aims to provide biodegradable polymer particles, wherein the polymer particles are copolymers of lactic acid and/or glycolic acid repeating units, and the particle size of the polymer particles is 10-150 mu m.

In a preferred embodiment of the present invention, the polymer fine particles have a particle size of 20 to 120. mu.m, preferably 30 to 100. mu.m.

In a preferred embodiment of the present invention, the weight average molecular weight of the polymer particles is 10,000-100,000, preferably 20,000-75,000, and more preferably 30,000-50,000.

In a preferred embodiment of the present invention, the repeating unit of the polymer microparticle is selected from any one of levolactic acid, dextrolactic acid, racemic lactic acid, and glycolic acid, or a combination thereof.

In a preferred embodiment of the present invention, the polymer microparticles are selected from a copolymer of any one or a combination of poly (L-lactic acid) (PLLA), poly (D-lactic acid) (PDLA), poly (racemic lactic acid) (PDLLA), poly (lactic-co-glycolic acid) (PLGA), and poly (glycolic acid) (PGA).

In a preferred embodiment of the present invention, the polymer fine particles have an irregular shape.

In a preferred embodiment of the present invention, the irregular shape of the polymer microparticles is selected from any one of or a combination of approximately square, approximately spherical, approximately rectangular, approximately rhombic, approximately triangular, approximately circular, approximately elliptical, approximately trapezoidal, approximately conical, and approximately cylindrical shapes.

In a preferred embodiment of the present invention, the irregular shape of the polymer fine particles is selected from any one of a sheet shape, a block shape, a spherical shape, a strip shape, a filament shape, and a granular shape, or a combination thereof.

In a preferred embodiment of the present invention, the irregular outer shape is selected from any one of a laminated shape and a wound shape, or a combination thereof.

In a preferred embodiment of the present invention, the polymer fine particles have a rough surface or a matte surface.

In a preferred embodiment of the present invention, the rough surface or the matte surface of the polymer fine particles has irregular pore diameters.

In a preferred embodiment of the present invention, the total heat of fusion of the polymer particles heated from 40 ℃ to 230 ℃ at a heating rate of 10 ℃/min is 40J/g to 80J/g, preferably 45J/g to 70J/g, and more preferably 55J/g to 65J/g.

Another object of the present invention is to provide a method for preparing biodegradable polymer microparticles, comprising the steps of: (1) dissolving a biodegradable polymer in a benign solvent; (2) dripping a poor solvent and crystallizing; (3) filtering and washing; (4) and (5) drying to obtain the product.

In a preferred embodiment of the present invention, the biodegradable polymer is a copolymer of lactic acid and/or glycolic acid repeating units.

In a preferred embodiment of the present invention, the benign solvent is selected from one or a combination of tetrahydrofuran, 1, 4-dioxane, dichloromethane, chloroform, N-dimethylformamide, dimethyl sulfoxide, ethylene glycol diethyl ether, ethylene glycol dimethyl ether, toluene and p-xylene.

In a preferred embodiment of the invention, the amount of the benign solvent is 5 to 50 times, preferably 10 to 40 times, and more preferably 12 to 20 times that of the biodegradable polymer.

In a preferred embodiment of the present invention, the poor solvent is selected from any one of methanol, ethanol, isopropanol, n-propanol, butanol, acetone, butanone, 4-methyl-2-pentanone, ethyl acetate, butyl acetate, isopropyl acetate, n-hexane, cyclohexane, n-heptane, and n-octane, or a combination thereof.

In a preferred embodiment of the present invention, the amount of the poor solvent is 30 to 90 times, preferably 40 to 80 times, and more preferably 50 to 70 times that of the biodegradable polymer.

In a preferred embodiment of the present invention, the preparation method of the biodegradable polymer comprises the following steps: (1a) adding L-lactide into a reaction vessel, heating and melting; (1b) adding an initiator and a catalyst into the L-lactide molten liquid, and keeping the temperature until the reaction is complete; (1c) cooling the reaction liquid to room temperature, adding a benign solvent, stirring and dissolving; (1d) and (3) dripping a poor solvent into the filtrate, crystallizing, filtering and drying to obtain the compound.

In a preferred embodiment of the present invention, the heating temperature in step (1a) or the reaction temperature in step (1b) is 50-200 ℃, preferably 100-160 ℃, and more preferably 120-140 ℃.

In a preferred embodiment of the present invention, the reaction time in step (1b) is 5 to 72 hours, preferably 12 to 60 hours, and more preferably 24 to 48 hours.

In the preferable technical scheme of the invention, the initiator is lauryl alcohol; the catalyst is selected from any one or combination of stannous isooctanoate, stannous chloride and zinc chloride, preferably selected from any one or combination of stannous isooctanoate and stannous chloride, and more preferably selected from stannous isooctanoate.

In a preferred embodiment of the present invention, the amount of the benign solvent is 3 to 25 times, preferably 5 to 20 times, and more preferably 10 to 15 times that of the L-lactide.

In a preferred embodiment of the present invention, the amount of the poor solvent is 30 to 70 times, preferably 40 to 60 times, and more preferably 45 to 55 times that of the L-lactide.

In a preferred embodiment of the present invention, the method for preparing the polymer microparticles comprises the step (5): the resulting polymer particles were sieved through a 200 mesh sieve.

In a preferred embodiment of the present invention, the polymer fine particles have a particle size of 10 to 150. mu.m, preferably 20 to 120. mu.m, and more preferably 30 to 100. mu.m.

In a preferred embodiment of the present invention, the polymer microparticles are selected from a copolymer of any one or a combination of poly (L-lactic acid) (PLLA), poly (D-lactic acid) (PDLA), poly (racemic polylactic acid) (PDLLA), poly (lactic-co-glycolic acid) (PLGA), and poly (glycolic acid) (PGA).

In a preferred embodiment of the present invention, the irregular shape of the polymer microparticles is selected from any one of a laminated shape and a wound shape, or a combination thereof.

In a preferred embodiment of the present invention, the rough surface or the matte surface of the polymer particles has irregular pore diameters.

It is another object of the present invention to provide a use of biodegradable polymer microparticles for enhancing the filling effect of an injectable filling.

In the preferable technical scheme of the invention, the filling effect of the injection filler is improved by any one or combination of three-dimensional full filling part, soft and natural filling part, shortened filling swelling time and prolonged filling maintaining time.

In a preferred embodiment of the present invention, the active ingredient of the injectable filling is selected from any one or a combination of biodegradable polymer particles and other types of injectable filling ingredients.

In a preferred embodiment of the present invention, the other type of injection filling component is selected from any one or a combination of collagen, hyaluronic acid, polymethyl methacrylate, polyacrylamide, silica gel, and autologous fat.

It is another object of the present invention to provide the use of biodegradable polymer microparticles for the preparation of resorbable bone engaging materials.

In a preferred embodiment of the present invention, the absorbable bone joining material is selected from any one or a combination of fracture fixation and repair materials, bone fragment fixation materials in bone connection, and bone block fixation materials in osteosynthesis.

In a preferred embodiment of the present invention, the absorbable bone joining material is selected from any one of an intervertebral fusion device, a bone plate, a bone nail, a bone screw, a bone pin, a rib nail, a bone rod, an internal spinal fixation device, a patella concentrator, bone wax, a sternum fixation nail, a medullary bone screw, a washer, a drill, and a vertebra or a combination thereof.

In a preferred embodiment of the present invention, the absorbable bone graft material is used for preventing and/or treating any one of cruciate ligament tear, knee joint injury, maxillofacial surgery, and knee joint laxity, or complications thereof.

The invention also aims to provide application of the biodegradable polymer particles in preparing surgical sutures, dental filling materials, ophthalmic implant materials, tissue engineering scaffold materials and drug controlled release materials.

It is another object of the present invention to provide an injectable implant composition comprising biodegradable polymer microparticles and hyaluronic acid in an amount of not more than 0.1%.

In a preferred embodiment of the present invention, the polymer microparticles in the composition are a copolymer of lactic acid and/or glycolic acid repeating units, and the particle size of the polymer microparticles is preferably 10 μm to 150 μm.

In a preferred embodiment of the present invention, the repeating unit is selected from any one of or a combination of levolactic acid, dextrolactic acid, racemic lactic acid and glycolic acid.

In a preferred embodiment of the present invention, the irregular shape of the polymer microparticles is selected from any one of or a combination of approximately square, approximately rectangular, approximately rhombic, approximately triangular, approximately circular, approximately elliptical, approximately trapezoidal, approximately conical, and approximately cylindrical shapes.

In a preferred embodiment of the present invention, the irregular shape of the polymer particles is selected from any one of a stacked shape and a wound shape, or a combination thereof.

In a preferred embodiment of the present invention, the content of the polymer particles in the composition is 3% to 30%, preferably 5% to 25%, and more preferably 10% to 20%.

In a preferred embodiment of the present invention, the hyaluronic acid in the composition is selected from any one of cross-linked hyaluronic acid and non-cross-linked hyaluronic acid, or a combination thereof.

In a preferred embodiment of the present invention, the weight average molecular weight of the hyaluronic acid is 600,000-2,300,000, preferably 800,000-2,000,000, and more preferably 1,500,000.

In a preferred embodiment of the present invention, the content of hyaluronic acid in the composition is not higher than 0.05%, preferably not higher than 0.04%, more preferably 0.02-0.04%.

In a preferred embodiment of the present invention, the content of hyaluronic acid in the composition is not 0.

In a preferred embodiment of the present invention, the injectable implant composition is a lyophilized powder preparation.

In a preferred technical scheme of the invention, the freeze-dried powder preparation contains 50% -90% of suspension stabilizer, 0.01% -5% of surfactant and optional buffering agent.

In the preferred technical scheme of the invention, the dosage of the suspension stabilizer in the freeze-dried powder preparation is 55-90%, preferably 60-90%, and more preferably 70-88%.

In the preferable technical scheme of the invention, the dosage of the surfactant in the freeze-dried powder preparation is 0.05% -4%, preferably 0.08% -3%, and more preferably 0.1% -2.5%.

In a preferred technical scheme of the invention, the suspension stabilizer is selected from any one of sucrose, maltose, lactose, fructose, dextran, mannitol, trehalose, sorbitol, xylitol, maltitol, oligosaccharide alcohol and polyethylene glycol or a combination thereof.

In a preferred embodiment of the present invention, the surfactant is selected from any one of stearic acid, sodium dodecyl sulfate, lecithin, alkyl glucoside, polysorbate, sorbitan fatty acid ester, poloxamer, or a combination thereof.

In a preferred technical scheme of the invention, the buffering agent is selected from any one of phosphate-phosphate, citric acid-citrate, EDTA-EDTA salt and citric acid-citrate or the combination thereof.

In a preferred embodiment of the present invention, the pH of the injectable implant composition is 4.5 to 7.5, preferably 5 to 7, and more preferably 5.5 to 6.5.

In a preferred technical scheme of the invention, the injection implant composition contains 10-20% of PLLA microparticles, 75-88% of mannitol, 0.1-2.5% of poloxamer and 0.02-0.05% of hyaluronic acid.

Another object of the present invention is to provide a method for preparing a lyophilized powder preparation of an injectable implant, comprising the steps of: suspending the polymer particles in an aqueous solution of a suspension stabilizer, a surfactant and optionally a buffer, and freeze-drying to obtain the polymer particles.

In a preferred technical scheme of the invention, the preparation method of the freeze-dried powder preparation comprises the following steps: weighing the required amount of the materials, putting the other components except the polymer particles into a closed container, adding water, stirring until the components are completely dissolved, then adding the PLLA particles, vacuumizing under the stirring condition, and freeze-drying to obtain the polymer particles.

In a preferred technical scheme of the invention, the preparation method of the freeze-dried powder preparation comprises the following steps: weighing mannitol, poloxamer and hyaluronic acid with required amounts, placing in a closed container, adding water, stirring, adding PLLA microparticles after dissolving completely, vacuumizing under stirring, and freeze drying to obtain the final product.

In the preferred technical scheme of the invention, the vacuum degree is-0.08 MPa.

In the preferred technical scheme of the invention, the stirring speed is 1500-.

It is another object of the present invention to provide a method for increasing the cellular affinity of PLLA polymer, comprising the steps of: (1) dissolving a biodegradable polymer in a benign solvent; (2) dripping a poor solvent and crystallizing; (3) filtering and washing; (4) and (5) drying to obtain the product.

In a preferred technical scheme of the invention, the preparation method further comprises the following step (5): the resulting polymer particles were sieved through a 200 mesh sieve.

In a preferred embodiment of the present invention, the irregular shape of the polymer particles is selected from any one of a sheet shape, a block shape, a spherical shape, a strip shape, a filament shape, and a granular shape, or a combination thereof.

It is another object of the present invention to provide the use of hyaluronic acid for the preparation of a composition for reducing the irritation of PLLA injection.

In a preferred technical scheme of the invention, the reduction of the PLLA injection irritation is selected from any one or a combination of reduction of injection pain, reduction of adverse reaction incidence and reduction of adverse reaction degree.

In a preferred embodiment of the present invention, the adverse reaction is selected from any one of red swelling, ecchymosis, bruise, edema, pimple, nodule, hardening of injection region, abscess, anaphylaxis, urticaria, skin hypertrophy and atrophy, angioedema, vascular embolism, telangiectasia, skin sarcoidosis, scar, skin discoloration, and blood oozing at the needle insertion site, or a combination thereof.

In a preferred embodiment of the present invention, the hyaluronic acid is selected from any one of cross-linked hyaluronic acid and non-cross-linked hyaluronic acid, or a combination thereof.

In a preferred embodiment of the present invention, the weight average molecular weight of hyaluronic acid in the composition is 600,000-2,300,000, preferably 800,000-2,000,000, and more preferably 1,500,000.

In a preferred embodiment of the present invention, the hyaluronic acid content of the composition is not higher than 0.1%, preferably not higher than 0.05%, more preferably not higher than 0.04%, and most preferably 0.02-0.04%.

The freeze-dried powder preparation of the invention is injected into rats subcutaneously, the application part of the freeze-dried powder preparation without hyaluronic acid slightly bleeds, and small erythema occurs, while the freeze-dried powder preparation added with hyaluronic acid does not have skin irritation reactions such as bleeding, erythema, edema and the like. The result shows that the hyaluronic acid added into the freeze-dried powder preparation can obviously reduce the injection irritation and improve the medication safety and the compliance.

The invention also aims to provide application of hyaluronic acid in improving the physical stability of reconstitution of a freeze-dried powder preparation.

In the preferable technical scheme of the invention, the improvement of the physical stability of the redissolution of the freeze-dried powder preparation is selected from any one or combination of reduction of the floating object on the liquid surface of the redissolution and prolongation of the sedimentation time of insoluble substances.

In a preferred embodiment of the invention, the extended insoluble settling time is selected from the group consisting of no visible settling in at least 3 minutes, preferably no visible settling in at least 5 minutes, more preferably no visible settling in at least 20 minutes, and most preferably no visible settling in at least 30 minutes.

In a preferred embodiment of the present invention, the content of hyaluronic acid in the lyophilized powder preparation is not higher than 0.1%, preferably not higher than 0.05%, more preferably not higher than 0.04%, and most preferably 0.02-0.04%.

In a preferred embodiment of the present invention, the content of hyaluronic acid in the lyophilized powder preparation is not 0.

In a preferred embodiment of the present invention, the dosage of the injection implant composition or the lyophilized powder preparation is related to the age, sex, filling site and other factors of the patient, and the using method comprises: adding appropriate amount of water for injection into lyophilized powder preparation, and shaking and mixing well before use.

In a preferred embodiment of the present invention, the injection site of the composition is selected from any one of the superficial dermis, the deep dermis, the subcutaneous layer, and the intradermal layer, or a combination thereof.

The invention also aims to provide application of the injection implant freeze-dried powder preparation in preparing subcutaneous injection fillers for patients.

In a preferred embodiment of the present invention, the injection filling site is selected from any one or a combination of the face, neck, abdomen, chest, buttocks, thigh, calf, upper arm and lower arm, and preferably the injection filling site is the face.

In a preferred embodiment of the present invention, the patient's symptoms are selected from any one of facial wasting, lipoatrophy, cheek sinking, eye socket sinking, skin wrinkles or a combination thereof.

In the preferable technical scheme of the invention, the injection implant freeze-dried powder preparation is applied to the preparation of the composition for treating the facial lipoatrophy of HIV-infected patients.

In the preferable technical scheme of the invention, the injection implant freeze-dried powder preparation is applied to the preparation of the composition for treating acne scars on hills and valleys.

In a preferred technical scheme of the invention, the injection implant freeze-dried powder preparation is used for preparing a composition for filling facial wrinkles by injection.

In a preferred embodiment of the present invention, the facial wrinkles are selected from any one of or a combination of the superficial to deep nasolabial folds, glabellar folds, forehead, outer canthus, and canthus.

Another object of the present invention is to provide a combination of the lyophilized powder preparation for injection implant, which is used in combination with any one or a combination of other types of injection fillers, anesthetics, anti-inflammatory agents, and anti-allergic agents.

In a preferred embodiment of the present invention, the other type of injection filler is selected from any one of collagen, hyaluronic acid, polymethyl methacrylate, polyacrylamide, silica gel, autologous fat, or a combination thereof.

In a preferred embodiment of the present invention, the anesthetic is selected from any one of lidocaine, procaine, tetracaine, bupivacaine, ropivacaine, diclofenac, morphine, hydrocodone, oxycodone, codeine, fentanyl, sodium pentobarbital, sodium phenobarbital, thiopental, aldochloroketone, ethyl carbamate, and chloral hydrate, or a combination thereof.

In a preferred embodiment of the present invention, the anti-inflammatory agent is selected from any one of a steroidal anti-inflammatory agent and a non-steroidal anti-inflammatory agent, or a combination thereof.

In a preferred embodiment of the present invention, the steroidal anti-inflammatory agent is selected from one of fluocinolone, hydrocortisone and betamethasone, or a combination thereof.

In a preferred embodiment of the present invention, the non-steroidal anti-inflammatory agent is selected from any one of aspirin, magnesium salicylate, sodium salicylate, choline magnesium salicylate, diflunisal, salsalate, ibuprofen, indomethacin, flurbiprofen, phenoxyibuprofen, naproxen, nabumetone, piroxicam, phenylbutazone, diclofenac, fenprofen, ketoprofen, ketorolac, tetrachlorofenamic acid, sulindac, and tolmetin, or a combination thereof.

In a preferred technical scheme of the invention, the antiallergic agent is any one or a combination of diphenhydramine, promethazine, chlorpheniramine, cromolyn sodium, ketotifen, betahistine, montelukast, zafirlust, salbutamol, calcium gluconate and glucocorticoid.

Unless otherwise indicated, when the present invention relates to percentages between liquids, said percentages are volume/volume percentages; the invention relates to the percentage between liquid and solid, said percentage being volume/weight percentage; the invention relates to the percentages between solid and liquid, said percentages being weight/volume percentages; the balance being weight/weight percent.

In order to clearly convey the scope of the invention, the invention is defined by the following terms:

1. the "weight average molecular weight" of the PLLA fine particles of the present invention is obtained by gel permeation chromatography using hexafluoroisopropanol as a solvent, and the value is calculated as polymethyl methacrylate.

2. The "heat of fusion" of the PLLA fine particles of the present invention was measured by DSC from 40 ℃ at a rate of 20 ℃/min to 230 ℃ in a nitrogen atmosphere.

3. The "particle diameter" of the PLLA fine particles of the present invention means a particle diameter corresponding to 90% of the particle diameter distribution (D90).

4. The PLLA particles of the invention have a particle size distribution determined by an ultra-high speed intelligent particle size analyzer under the air pressure of 2.0barg and at a sample injection speed of 35% and a hopper gap of 1.50 mm.

5. The scanning electron microscope image of the PLLA particles is obtained by adopting a scanning electron microscope (model: Thermo-prism E) to amplify 1000 times and 5000 times for detection.

Compared with the prior art, the invention has the following beneficial technical effects:

1. the PLLA particles of the present invention have an irregular, unsmooth or rough microscopic appearance. The irregular shape contains a porous structure or forms a support structure, so that the contact area of the PLLA particles and cells is increased, the adhesion capacity and the residence time of the cells on the porous structure or the support structure are improved, the cell affinity of the PLLA particles is obviously improved, collagen cells are stimulated to feel physical and mechanical microenvironment stimulation and respond to the physical and mechanical microenvironment stimulation, and the collagen growth of an organism is stimulated and accelerated.

2. The hyaluronic acid is added into the biodegradable injection filling composition, so that the filling effect or filling effect of the composition is obviously improved, wrinkles are removed, the beauty of facial skin is enhanced, and the suspension stability of PLLA particles after freeze-drying and redissolving is favorably improved. The hydrophilicity of the hyaluronic acid obviously improves the hydrophobic property of the surface of the PLLA polymer scaffold, and promotes the adhesion growth of collagen cells on the surface of the PLLA polymer scaffold. The water-absorbing property of the hyaluronic acid is beneficial to reducing the hydrolysis and degradation of ester bonds of the PLLA and reducing the stimulation of acidic degradation products to surrounding tissues.

3. The hyaluronic acid dosage in the biodegradable injection filling composition scientifically screened by the invention can obviously improve the effects of smoothing wrinkles, reshaping skin contours, delaying aging and the like of the composition. Hyaluronic acid takes effect rapidly in vivo, and makes skin water full, fine and smooth; PLLA stimulates progressive collagen proliferation and the cosmetic effect is natural and lasting.

4. The biodegradable injection filler or the composition thereof is safe and effective, is simple and convenient to prepare, and is suitable for industrial mass production.

Drawings

FIG. 1(a) SEM test results of 1000 times of polymer particles in example 4;

FIG. 1(b) SEM examination of example 4 polymer particles at 5000 times;

FIG. 2 the results of examining the particle size distribution of the polymer fine particles of example 3;

FIG. 3(a) the results of comparing the sedimentation tendency of the lyophilized powder for injection of example 10 after reconstitution;

FIG. 3(b) is a graph showing the comparative results of the sedimentation tendency of the lyophilized powder for injection of example 14 after reconstitution.

Detailed Description

The present invention is described below with reference to examples, but the scope of the present invention is not limited to the examples.

Example 1Preparation of PLLA polymers

Adding 500g of L-lactide into a 2000mL single-neck bottle, heating to 130 ℃ under the protection of nitrogen until the L-lactide is completely melted, adding 0.15g of stannous isooctanoate and 1.5g of lauryl alcohol, keeping the temperature at 130 ℃ for reaction for 24 hours, cooling the reaction liquid to room temperature, adding 1L of dichloromethane, stirring for dissolving, filtering, transferring the obtained solution into a 50L reaction kettle, adding 4L of dichloromethane, dropwise adding 25L of methanol, crystallizing at room temperature, filtering, and drying a filter cake at 50 ℃ to obtain a PLLA polymer with the weight-average molecular weight of 36000.

Example 2Preparation of PLLA polymers

Adding 500g of L-lactide into a 2000mL single-mouth bottle, heating to 120 ℃ under the protection of nitrogen until the L-lactide is completely melted, adding 0.1g of stannous chloride and 1.2g of lauryl alcohol, keeping the temperature at 120 ℃ for reaction for 48 hours, cooling the reaction liquid to room temperature, adding 1L of trichloromethane, stirring for dissolving, filtering, transferring the solution into a 50L reaction kettle, adding 4L of trichloromethane, dropwise adding 25L of n-heptane, crystallizing at room temperature, filtering, and drying a filter cake at 50 ℃ to obtain a PLLA polymer with the weight-average molecular weight of 39000.

Example 3Preparation of PLLA Polymer microparticles

Weighing 200g of PLLA polymer prepared in example 1, adding 4L of tetrahydrofuran, stirring for dissolving, slowly dropwise adding 12L of anhydrous methanol, stirring for about 1 hour after dropwise adding, filtering, leaching a filter cake with the anhydrous methanol, drying in vacuum at 35 ℃, and sieving with a 200-mesh sieve to obtain PLLA particles, wherein the heat of fusion is 54.3J/g, and the particle size distribution is shown in figure 1.

Example 4Preparation of PLLA Polymer microparticles

200g of PLLA polymer prepared in example 2 is weighed, 2.9L of 1, 4-dioxane is added, 14.6L of n-heptane is slowly dropped after stirring and dissolving, after dropping, stirring is carried out for about 1 hour, filtering is carried out, leaching is carried out by n-heptane, vacuum drying is carried out at 35 ℃, a sample is sieved by a 200-mesh sieve, and PLLA particles are obtained, wherein the heat of fusion is 55.6J/g. The scanning electron micrograph of the particles is shown in FIG. 2.

Examples 5 to 9Preparation of PLLA lyophilized powder formulation

The compositions of PLLA lyophilized powder for injection of examples 5-9 are shown in table 1, and the preparation method thereof comprises the following steps:

(1) weighing mannitol, poloxamer and hyaluronic acid with required amounts, placing the weighed mannitol, poloxamer and hyaluronic acid into a triangular flask, adding water until the volume of the mixture reaches 200mL, stirring the mixture until the mixture is completely dissolved, and adding the PLLA microparticles prepared in the example 3;

(2) sealing the triangular bottle mouth, and vacuumizing to below-0.08 MPa;

(3) stirring at 2000r/min for 30 min;

(4) and (3) carrying out freeze drying according to the freeze drying process described in the table 2 to obtain the product.

TABLE 1 lyophilized powder formulations

Numbering	PLLA microgranules (mg)	Mannitol (mg)	Poloxamer (mg)	Hyaluronic acid (mg)
					Example 5	150	1000	10	0.5
Example 6	226	905	26	0.5
					Example 7	176	1471	17	0.5
Example 8	162	1085	1.25	0.5
					Example 9	273	1380	16.82	0.5

TABLE 2 Freeze drying Process

Step (ii) of	Temperature (. degree.C.)	Vacuum degree (μ bar)	Time of operation
				Prefreezing	-50	200	Over 2h
Evacuation	-20	200	\
				Drying	-10	200	4h
Drying	-5	200	9h
				Drying
	0	200	1h
				Drying	5	200	1h
Drying	10	200	1h
				Drying	20	200	1h
Drying	30	\	6h

Examples 10 to 16Redissolution stability and pH value research of PLLA polymer lyophilized powder preparation

1. Experimental study on character and settling time of redissolved matter

Weighing 150mg of PLLA particles, 1000mg of mannitol and 10mg of poloxamer, adding hyaluronic acid in the weight ratio shown in Table 3, and preparing the freeze-dried powder products of examples 10-16 according to the preparation method shown in examples 5-9.

Weighing 1g of the freeze-dried powder products of the embodiments 10 to 16 respectively, fully mixing the freeze-dried powder products with 5mL of sterile water for injection, and observing the characters and the settling time of the re-dissolved freeze-dried powder. The results are shown in Table 3.

TABLE 3 proportioning study experiment of hyaluronic acid

As can be seen from the results in Table 3, the lyophilized powder products of examples 12-16 can be uniformly dispersed in water for injection after reconstitution, and hyaluronic acid can significantly improve the redispersion performance of the PLLA lyophilized powder preparation. When the dosage of the hyaluronic acid is higher than 0.05%, a large amount of foams appear on the upper layer of the liquid surface of the redissolved matter; when the amount of hyaluronic acid is less than 0.01%, the reconstituted substance rapidly settles and separates within 5 minutes.

2. Redissolving particle count experiment

Weighing 1g of the freeze-dried powder products of the embodiments 10 and 14 respectively, fully mixing the freeze-dried powder products with 5mL of sterile water for injection, evenly dividing the mixed solution into an upper layer, a middle layer and a lower layer, respectively extracting samples of each layer in 0min, 2min, 5min and 10min, and detecting the number of particles in the samples (repeating three parallel samples). The results are shown in FIG. 3.

The results in FIG. 3 show that the particles in each layer of the lyophilized powder reconstituted in example 10 are not stably distributed, and the particles in the lower layer gradually increase and the particles in the upper layer gradually decrease during 0-10 min. Example 14 lyophilized powder reconstitute no significant change in number of particles in each layer occurred within 10 min. The addition of hyaluronic acid can enable PLLA particles to be stably suspended in the compound solution, and the physical stability of the freeze-dried powder compound is obviously improved.

3. Test for measuring pH value of reconstituted substance

1g of the lyophilized powder product of example 14 was weighed, mixed well with 5mL of sterile water for injection, and then measured for pH by an acidimeter.

Example 14 reconstitution of lyophilized powder product pH 5.5.

The above description of the specific embodiments of the present invention is not intended to limit the present invention, and those skilled in the art may make various changes and modifications according to the present invention without departing from the spirit of the present invention, which is defined in the appended claims.

Claims

1. Use of biodegradable polymer particles for improving the filling effect of an injection filling, wherein the polymer particles are copolymers of lactic acid and/or glycolic acid repeating units, the particle size of the polymer particles is 10-150 μm, the weight average molecular weight of the polymer particles is 10,000-100,000, the repeating units of the polymer particles are selected from any one or combination of levolactic acid, dextrolactic acid, racemic lactic acid and glycolic acid, the polymer particles have irregular shapes, the polymer particles have rough surfaces or non-smooth surfaces, and the rough surfaces or the non-smooth surfaces of the polymer particles have irregular pore sizes; the irregular shape of the polymer particles is selected from any one of approximately square, approximately spherical, approximately rectangular, approximately rhombic, approximately triangular, approximately circular, approximately elliptical, approximately trapezoidal, approximately conical, approximately cylindrical, stacked, wound or a combination thereof.

2. The use according to claim 1, wherein the weight average molecular weight of the polymer particles is 20,000-75,000.

3. The use according to claim 2, wherein the weight average molecular weight of the polymer particles is 30,000-50,000.

4. The use according to claim 1, wherein the polymer microparticles are selected from poly-L-lactic acid, poly-D-lactic acid, poly-racemic lactic acid, poly-lactic acid/glycolic acid copolymer, and copolymer formed by any one or combination of poly-glycolic acid.

5. Use according to claim 1, wherein the polymer particles have a total heat of fusion of 40 to 80J/g from 40 ℃ to 230 ℃ at a heating rate of 10 ℃/min.

6. Use according to claim 5, wherein the polymer particles have a total heat of fusion of 45J/g to 70J/g from 40 ℃ to 230 ℃ at a heating rate of 10 ℃/min.

7. Use according to claim 6, wherein the polymer particles have a total heat of fusion of 55J/g to 65J/g from 40 ℃ to 230 ℃ at a heating rate of 10 ℃/min.

8. A method of preparing biodegradable polymer microparticles according to any one of claims 1 to 7 for use in an application to enhance the filling effect of an injectable filling, comprising the steps of: (1) dissolving a biodegradable polymer in a benign solvent; (2) dripping a poor solvent and crystallizing; (3) filtering and washing; (4) drying to obtain the product; the poor solvent in the step (2) is selected from any one of methanol, ethanol, isopropanol, n-propanol, butanol, acetone, butanone, 4-methyl-2-pentanone, ethyl acetate, butyl acetate, isopropyl acetate, n-hexane, cyclohexane, n-heptane, n-octane or a combination thereof.

9. The preparation method according to claim 8, wherein the benign solvent in the step (1) is selected from any one of tetrahydrofuran, 1, 4-dioxane, dichloromethane, chloroform, N-dimethylformamide, dimethylsulfoxide, ethylene glycol diethyl ether, ethylene glycol dimethyl ether, toluene, and p-xylene, or a combination thereof.

10. The method according to claim 8, wherein the amount of the benign solvent used in the step (1) is 5 to 50 times that of the biodegradable polymer.

11. The method according to claim 10, wherein the amount of the benign solvent used in the step (1) is 10 to 40 times that of the biodegradable polymer.

12. The method according to claim 11, wherein the amount of the benign solvent used in the step (1) is 12 to 20 times that of the biodegradable polymer.

13. The method according to claim 8, wherein the amount of the poor solvent used in the step (2) is 30 to 90 times that of the biodegradable polymer.

14. The method according to claim 13, wherein the amount of the poor solvent used in the step (2) is 40 to 80 times that of the biodegradable polymer.

15. The method according to claim 14, wherein the amount of the poor solvent used in the step (2) is 50 to 70 times that of the biodegradable polymer.

16. The method of producing according to any one of claims 8 to 15, the method of producing the biodegradable polymer comprising the steps of: (1a) adding L-lactide into a reaction vessel, heating and melting; (1b) adding an initiator and a catalyst into the L-lactide molten liquid, and keeping the temperature until the reaction is complete; (1c) cooling the reaction liquid to room temperature, adding a benign solvent, stirring and dissolving; (1d) and (3) dripping a poor solvent into the filtrate, crystallizing, filtering and drying to obtain the compound.

17. The production method according to claim 16, wherein the reaction temperature in the step (1b) is 50 to 200 ℃.

18. The preparation method according to claim 17, wherein the reaction temperature in the step (1b) is 100-160 ℃.

19. The preparation method according to claim 18, wherein the reaction temperature in the step (1b) is 120-140 ℃.

20. The production method according to claim 16, wherein the reaction time in the step (1b) is 5 to 72 hours.

21. The production method according to claim 20, wherein the reaction time in the step (1b) is 12 to 60 hours.

22. The production method according to claim 21, wherein the reaction time in the step (1b) is 24 to 48 hours.

23. The method of claim 16, wherein the initiator is lauryl alcohol.

24. The preparation method according to claim 16, wherein the catalyst is selected from any one of stannous isooctanoate, stannous chloride, zinc chloride or a combination thereof.

25. The preparation method according to claim 24, wherein the catalyst is selected from any one of stannous isooctanoate, stannous chloride or a combination thereof.

26. The method of claim 25, wherein the catalyst is stannous isooctanoate.

27. The preparation method according to claim 16, wherein the benign solvent in the step (1c) is selected from any one of tetrahydrofuran, 1, 4-dioxane, dichloromethane, chloroform, N-dimethylformamide, dimethylsulfoxide, ethylene glycol diethyl ether, ethylene glycol dimethyl ether, toluene, and p-xylene, or a combination thereof.

28. The production method according to claim 16, wherein the amount of the benign solvent used in the step (1c) is 3 to 25 times that of the L-lactide.

29. The method according to claim 28, wherein the amount of the benign solvent used in the step (1c) is 5 to 20 times that of the L-lactide.

30. The method according to claim 29, wherein the amount of the benign solvent used in the step (1c) is 10 to 15 times that of the L-lactide.

31. The preparation method according to claim 16, wherein the poor solvent in step (1d) is selected from any one of methanol, ethanol, isopropanol, n-propanol, butanol, acetone, butanone, 4-methyl-2-pentanone, ethyl acetate, butyl acetate, isopropyl acetate, n-hexane, cyclohexane, n-heptane, n-octane, or a combination thereof.

32. The method according to claim 16, wherein the amount of the poor solvent used in the step (1d) is 30 to 70 times that of the L-lactide.

33. The method according to claim 32, wherein the amount of the poor solvent used in the step (1d) is 40 to 60 times that of the L-lactide.

34. The method according to claim 33, wherein the amount of the poor solvent used in the step (1d) is 45 to 55 times that of the L-lactide.

35. The production method according to claim 8, further comprising step (5): the resulting polymer particles were sieved through a 200 mesh sieve.

36. A method for increasing the cell affinity of a biodegradable polymer microparticle in a use according to any one of claims 1-7 or a biodegradable polymer microparticle obtained by the preparation method according to any one of claims 8-35, comprising the steps of: (1) dissolving a biodegradable polymer in a benign solvent; (2) dripping a poor solvent and crystallizing; (3) filtering and washing; (4) and (5) drying to obtain the product.

37. The method of claim 36, wherein the benign solvent in step (1) is selected from the group consisting of tetrahydrofuran, 1, 4-dioxane, dichloromethane, chloroform, N-dimethylformamide, dimethylsulfoxide, ethylene glycol diethylether, ethylene glycol dimethylether, toluene, p-xylene, and any one or combination thereof.

38. The method of claim 36, wherein the amount of benign solvent used in step (1) is 5-50 times that of the biodegradable polymer.

39. The method of claim 38, wherein the amount of benign solvent used in step (1) is 10-40 times that of the biodegradable polymer.

40. The method of claim 39, wherein the amount of benign solvent used in step (1) is 12-20 times that of the biodegradable polymer.

41. The method of claim 36, wherein the poor solvent in step (2) is selected from any one of methanol, ethanol, isopropanol, n-propanol, butanol, acetone, butanone, 4-methyl-2-pentanone, ethyl acetate, butyl acetate, isopropyl acetate, n-hexane, cyclohexane, n-heptane, n-octane, or a combination thereof.

42. The method of claim 36, wherein the amount of the poor solvent used in step (2) is 30-90 times that of the biodegradable polymer.

43. The method of claim 42, wherein the amount of the poor solvent used in step (2) is 40-80 times that of the biodegradable polymer.

44. The method of claim 43, wherein the amount of the poor solvent used in step (2) is 50-70 times that of the biodegradable polymer.

45. The method of claim 36, further comprising the step (5): the resulting polymer particles were sieved through a 200 mesh sieve.

46. Use of biodegradable polymer microparticles obtained by the preparation process according to claims 8 to 35 for improving the filling effect of injectable fillers.

47. The use of claim 1-7 or 46, wherein the filling effect of the injected filler is improved by any one or combination of three-dimensional filling at the filling site, soft and natural filling site, shortening of filling swelling time and prolonging of filling maintaining time.

48. The use according to claim 1-7 or 46, wherein the active ingredient of the injectable filling is selected from any one or a combination of biodegradable polymeric microparticles, other types of injectable filling ingredients.

49. The use according to claim 48, wherein said other type of injectable filling composition is selected from any one or combination of collagen, hyaluronic acid, polymethylmethacrylate, polyacrylamide, silica gel, autologous fat.

50. Use of biodegradable polymeric microparticles for use according to any one of claims 1 to 7 or obtained by the preparation process according to claims 8 to 35 for the preparation of resorbable bone engaging materials.

51. The use according to claim 50, wherein the absorbable bone joining material is selected from any one of fracture fixation repair material, bone fragment fixation material in bone connection, bone block fixation material in osteosynthesis, or a combination thereof.

52. The use according to claim 50, wherein the absorbable bone joining material is selected from any one of an interbody fusion cage, a bone plate, a bone screw, a bone pin, a rib nail, a bone rod, an intraspinal fixation device, a patellar concentrator, bone wax, a sternal fixation nail, a medullary bone screw, a washer, a drill, a hand vertebra, or a combination thereof.

53. Use of the absorbable bone engaging material of claim 50 in the manufacture of a material for the prevention and/or treatment of any one of cruciate ligament tears, knee joint injuries, maxillofacial surgery, knee joint laxity, or complications thereof.

54. Use of biodegradable polymer particles according to any one of claims 1 to 7 or obtained by the process according to claims 8 to 35 for the preparation of surgical sutures, dental filling materials, ophthalmic implant materials, tissue engineering scaffold materials, controlled drug release materials.