KR102427305B1 - A manufacturing method of double encapsulated biodegradable polymer microsphere, and the injection composition containing the same - Google Patents

Abstract

The present invention relates to a method for manufacturing biodegradable polymeric microspheres capable of encapsulating water-soluble bioactive substances in low loss and high content through double encapsulation, and more particularly, to a method for effectively encapsulating water-soluble bioactive substances such as water-soluble vitamins and water-soluble peptides into microspheres of a certain size. Microspheres encapsulated with water-soluble bioactive substances according to the present invention can obtain uniform and constant microspheres with high drug content and encapsulation rate without using a hydrophilic organic solvent. In addition, drug-encapsulated microspheres can be made into a freeze-dried formulation for topical administration and used as sustained-release long-acting medicines, tissue regeneration medical devices, cosmetic microbeads, and cosmetic compositions.

Description

{A manufacturing method of double encapsulated biodegradable polymer microsphere, and the injection composition containing the same}

The present invention relates to a method for producing biodegradable polymeric microspheres capable of encapsulating a water-soluble physiologically active substance with a low loss and high content through double encapsulation, and to an injection for topical administration comprising the polymeric microspheres, and more particularly, to a water-soluble vitamin, water-soluble It relates to a method for effectively encapsulating water-soluble physiologically active substances such as peptides in microspheres of a certain size.

Microsphere manufacturing technology for biodegradable polymers is a technology that is very popular in the field of cosmetic surgery and skin care, as well as in the field of long-lasting sustained-release drug delivery through drug encapsulation [Heller, J. et al., Controlled release of water- soluble macromolecules from bioerodible hydrogels, Biomaterials, 4, 262-266, 1983; Langer, R., New methods of drug delivery, Science, 249, 1527-1533, 1990; Langer, R., Chem. Eng. Commun., 6, 1-48, 1980; Langer, R. S. and Peppas, N. A., Biomaterials, 2, 201-214, 1981; Heller, J., CRC Crit. Rev. Ther. Drug Cattrier Syst., 1(1), 39-90, 1984; Holland, S. J. Tighe, B. J. and Gould, P. L., J. Controlled Release, 155-180, 1986].

Recently, a lot of depot formulations through fillers and drug encapsulation using biodegradable polymer microspheres have been developed, but there are various problems in application due to the inconsistent particle shape and size. For example, because the shape and size of the particles are not constant, a thick needle must be used to prevent blockage, so compliance with the patient is low. In addition, when the drug is encapsulated, an initial burst effect occurs, the release rate of the drug is not controlled at a constant rate for a certain period of time, and the drug is not released 100% due to incomplete release in vivo. It has a major problem in that it is difficult to control the release rate [Crotts, G. and Park, T.G., J. Control. Release, 44, 123-134, 1997; Leonard, N.B., Michael, L. H., Lee, M.M. J. Pharm. Sci., 84, 707-712]. In addition, most of the developed products are encapsulation technologies for poorly water-soluble active substances, and the encapsulation technologies for water-soluble physiologically active substances such as peptides and vitamins are very limited.

As an existing technology, there is a method of encapsulating a peptide salt in a water-insoluble polymer (Registration of Korea 10-1411349), and there is a method of encapsulating a drug through an ionic complex of a peptide salt and a water-insoluble polymer. This method is similar to the method of encapsulating poorly soluble physiologically active substances, and has a disadvantage in that the encapsulated drug content drops to less than 5%.

As a method of increasing the content of water-soluble drugs, Korean Patent Nos. 10-1583351 and 10-1663560 disclose alcohols or polar aprotic solvents (polar aprotic solvents) that mix water-soluble active substances with water. After dissolving it using a polar aprotic solvent), a biodegradable polymer is dissolved in an organic solvent such as chloromethane, and then an O/W emulsion is made in a large amount of water to make microspheres by drying in water.

In this method, when the amount of a solvent such as alcohol mixed with water increases, an emulsion cannot be formed or the encapsulation rate of the drug is lowered, and the content can be slightly increased, but the encapsulation rate is lowered. In addition, this is a method using the traditional solvent emulsification method, and it is difficult to control the size of the microspheres, so the yield drops to half in the powder process to purify particles of the desired size, and since a large amount of solvent is used, large-scale production is required. equipment is needed

Therefore, in manufacturing microspheres for encapsulating water-soluble physiologically active substances, there is a need for a method for manufacturing microspheres that have a constant size while increasing the drug content and encapsulation rate, and are economical and easy to mass-produce.

Republic of Korea Patent No. 10-1411349 Republic of Korea Patent No. 10-1583351 Republic of Korea Patent No. 10-1663560

The present invention is to provide a system for producing double-encapsulated biodegradable polymer microspheres for topical administration that can effectively encapsulate a water-soluble drug without using a hydrophilic organic solvent, and allows the microspheres encapsulated with a water-soluble drug to be used as an injection for topical administration. want to The microspheres encapsulated with a water-soluble drug according to the manufacturing method of the present invention can be used as long-acting sustained-release injections, medical devices for fillers, or cosmetic compositions.

The present invention for solving the above problems provides a method for producing double-encapsulated biodegradable polymer microspheres for topical administration, comprising the following steps.

(1) making a W/O emulsion using a hydrophobic membrane with an aqueous solution in which a surfactant and a water-soluble physiologically active substance are dissolved, and an organic solution in which a biodegradable polymer is dissolved in an organic solvent;

(2) preparing an O/W emulsion using an aqueous solution containing a surfactant and a hydrophilic membrane for the prepared W/O emulsion;

(3) removing the organic solvent from the W/O/W solution and curing to produce microspheres;

(4) purifying the microspheres, and preparing a freeze-dried formulation for topical administration containing the purified microspheres and an excipient for dispersion.

In this case, the pores of the hydrophobic membrane are 0.1 μm to 10 μm, and the pores of the hydrophilic membrane are 10 to 300 μm.

In addition, the water-soluble physiologically active substance of step (1) is characterized in that it is a water-soluble vitamin or a water-soluble peptide.

In addition, the surfactant of step (1) is polyvinyl alcohol (Polyvinyl alcohol), polyoxyethylene sorbitan (Polyoxyethylene sorbitan) and its salt, soybean lecithin (soybean Lecithin), and monoglyceride (monoglyceride) containing at least one characterized in that

In addition, the biodegradable polymer of step (1) is polylactic acid (PLA) and its isomers (Poly L-Lactic acid, Poly D-Lactic acid), polyglycolic acid (PGA), polycaprolactone ( Polycaprolactone, PCL), polydioxanone (PDO), polylactic acid-glycolic acid (Poly Lactic acid-glycolic acid, PLGA) is selected from, the average molecular weight of the polymer is characterized in that 10,000 to 200,000.

In addition, the organic solvent of step (1) includes at least one of chlorinated hydrocarbons, hydrocarbons, perfluoroalcohol, EA (Ethyl ester), Ether series, DMF (N,N-Dimethyl formamide), DMSO (Dimethyl sulfoxide), The content of the biodegradable polymer dissolved in the organic solvent is characterized in that 1 to 20% by weight.

In addition, the surfactant of step (2) includes at least one of polyvinyl alcohol, polyoxyethylene sorbitan and its salts, soybean lecithin, and monoglyceride, , The surfactant is characterized in that it contains 1 to 10% by weight based on the aqueous solution.

In addition, the size of the microspheres in step (3) is characterized in that 10 to 300㎛.

In addition, the dispersing excipients of step (4) include carboxymethyl cellulose and its salts, alginic acid and its salts, hyaluronic acid and its salts, dextran and its salts, It includes at least one of collagen, gelatin, and elastin, and the content of the dispersion excipient is 1 to 30% by weight.

In addition, the steps (1) to (4) are characterized in that it consists of a continuous process.

Furthermore, the present invention provides an injection for topical administration comprising 10 to 80% by weight of the polymer microspheres prepared by the above preparation method, based on a freeze-dried formulation.

At this time, the injection for topical administration is characterized in that any one of injections used as depot injections containing water-soluble physiologically active substances, fillers for tissue reconstruction and tissue regeneration, and cosmetic microbead compositions are used.

According to the present invention as described above, it is possible to obtain biodegradable polymer microspheres of a certain size encapsulated with a water-soluble physiologically active material.

In other words, according to the manufacturing method of the present invention, a) preparing a W/O emulsion using a membrane with a mixture of an aqueous solution in which a surfactant and a water-soluble physiologically active substance are dissolved and a biodegradable polymer in an organic solvent; b) preparing an O/W emulsion using an aqueous solution containing a surfactant and a membrane for the prepared W/O emulsion; c) removing the organic solvent from the W/O/W solution and curing it into microspheres; d) purifying the microspheres, and preparing a freeze-dried formulation for topical administration containing the purified microspheres and an excipient for dispersion.

In addition, the device embodying the present invention includes: a) a primary membrane emulsification device for making a W/O emulsion by passing an aqueous solution in which a surfactant and a water-soluble physiologically active substance are mixed; b) a secondary film emulsification device for making an O/W emulsion by passing the W/O emulsion prepared above; c) a device for removing the organic solvent from the W/O/W solution and curing it into microspheres.

The present inventors can prepare microspheres encapsulated with a high content of water-soluble physiologically active substances in a simple way through a continuous multi-layer emulsification device, and in addition to preparing microspheres having a constant size and a constant drug release rate, freeze-dried formulations of microspheres to maximize the efficiency of topical administration.

The microspheres encapsulated with the water-soluble physiologically active material according to the present invention have high drug content and encapsulation rate without using a hydrophilic organic solvent, and uniform and uniform microspheres can be obtained. In addition, the drug-encapsulated microspheres can be made into a freeze-dried formulation for topical administration and used as sustained-release long-acting medicines, tissue regeneration medical devices, cosmetic microbeads, and cosmetic compositions.

1 is a flowchart schematically illustrating a method for preparing double-encapsulated biodegradable polymer microspheres according to an embodiment of the present invention.
2 is a conceptual diagram schematically illustrating a system for continuously manufacturing double-encapsulated biodegradable polymer microspheres according to an embodiment of the present invention.
3 is an electron micrograph of double-encapsulated biodegradable polymer microspheres according to an embodiment of the present invention.
4 is an optical micrograph of double-encapsulated biodegradable polymer microspheres encapsulated with water-soluble dyes according to an embodiment of the present invention.
5 is an electron microscope photograph of biodegradable polymer porous microspheres according to an embodiment of the present invention.
6 is an electron micrograph of a cross-section of a freeze-dried formulation containing double-encapsulated biodegradable polymer microspheres according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail based on specific examples. However, these examples are provided to help the understanding of the present invention, the present invention may be implemented in various different forms, and the scope is not limited to the embodiments described herein.

1 is a schematic diagram of a process showing the process of making double encapsulated microspheres, passing through a hydrophobic membrane having small pores to make a primary W/O emulsion (S10), passing through a hydrophilic membrane having large pores 2 A step of making a tea O/W emulsion (S20), a step of curing the microspheres while evaporating the organic solvent from the W/O/W solution in the emulsion state (S30), a microsphere tablet through a filter and a freeze-dried formulation for topical administration The manufacturing step (S40) is shown.

S10 : Disperse in the organic solvent in which the biodegradable polymer is dissolved while passing the aqueous solution in which the surfactant and the water-soluble physiologically active substance are mixed through the membrane of small pores.

As the water-soluble physiologically active substance, pharmaceutically water-soluble physiologically active substances and pharmaceutically acceptable salts may be used without limitation. For example, although not particularly limited thereto, water-soluble vitamins, peptide pharmaceuticals, and the like may be mentioned. Water-soluble vitamins include vitamin B1 (Thiamine), vitamin B2 (riboflavin), vitamin B3 (niacin), vitamin B5 (pantothenic acid), vitamin B6 (pyridoxine), vitamin B7 (Biotin), vitamin B12 (Cobalamin), vitamin C (Ascorbic). acid) and the like. Peptides include LHRH and its analogues, somatostatin and its analogues, glucagon-like peptide (GLP), parathyroid hormone and its analogues, insulin-like growth factor, epidermal growth factor, platelet-derived growth factor, fibroblast growth factor, growth and hormone releasing factors, and pharmaceutically acceptable salts thereof.

As the surfactant, all of anionic, cationic, or amphoteric surfactant may be used. The surfactant may be polyvinyl alcohol, polyoxyethylene sorbitan and its salts, soybean lecithin, and monoglyceride, for example, polyoxyethylene sorbitan. Tan monolaurate (Twin 20 products), Polyoxyethylene Sorbitan Monopalmitate (Twin 40 products), Polyoxyethylene Sorbitan Monostearate (Twin 60 products), Polyoxyethylene Sorbitan Monooleate (Twin 80 products) ), and polyoxyethylene sorbitan trioleate (Twin 85 product). When polyvinyl alcohol is used as the surfactant, the polyvinyl alcohol may have an average molecular weight of 50,000 to 200,000. In addition, the content of polyvinyl alcohol may be included in an amount of 1 to 10% by weight based on the emulsion solution. Outside the above range, the emulsification action of polyvinyl alcohol acting as a surfactant is weakened, making it difficult to form microspheres.

The biodegradable polymer is polylactic acid (PLA) and its isomers (Poly-L-lactic acid, Poly-D-lactic acid), polyglycolic acid (PGA), polycaprolactone (PCL) , polydioxanone (Polydioxanone, PDO), polylactic acid-glycolic acid (Poly Lactic acid-glycolic acid, PLGA) is selected. The average molecular weight of the biodegradable polymer may be 20,000 to 200,000. If the average molecular weight of the biodegradable polymer is less than 20,000, the decomposition rate is high, and the value decreases as a material for tissue repair, tissue regeneration, or drug delivery. It is difficult to make microspheres of The content of the biodegradable polymer dissolved in the organic solvent may be 1 to 20% by weight. If the content of biodegradable polymer is less than 1%, the strength of the generated microspheres is weak and not suitable for drug encapsulation. .

The membrane may have hydrophobicity, and pores of the membrane may be 0.1 to 10 μm. If the pore size of the membrane is less than 0.1 μm, it is not suitable because high pressure is required.

The organic solvent includes at least one of chlorinated hydrocarbons, hydrocarbons, perfluoroalcohol, ethyl ester (EA), ether series, N,N-dimethyl formamide (DMF), and dimethyl sulfoxide (DMSO).

S20 : While passing the W/O emulsion through a large-pore membrane, the surfactant is dispersed in an aqueous solution.

As the surfactant, all of anionic, cationic, or amphoteric surfactant may be used. The surfactant may be polyvinyl alcohol, polyoxyethylene sorbitan and its salts, soybean lecithin, and monoglyceride, for example, polyoxyethylene Sorbitan Monolaurate (Twin 20 Product), Polyoxyethylene Sorbitan Monopalmitate (Twin 40 Product), Polyoxyethylene Sorbitan Monostearate (Twin 60 Product), Polyoxyethylene Sorbitan Monooleate (Twin 80 Product) product), and polyoxyethylene sorbitan trioleate (Twin 85 product). When polyvinyl alcohol is used as the surfactant, polyvinyl alcohol may have an average molecular weight of 50,000 to 200,000. In addition, the content of polyvinyl alcohol may be included in an amount of 1 to 10% by weight based on the emulsion solution. Outside the above range, the emulsification action of polyvinyl alcohol acting as a surfactant is weakened, making it difficult to form microspheres.

The membrane may have hydrophilicity, and pores of the membrane may be 10 to 300 μm. When the pores of the membrane are less than 10 μm, the encapsulation rate decreases when making the W/O emulsion, and when it exceeds 300 μm, it is difficult to control the size of the particles and the injection pressure increases.

S30 : While slowly stirring the emulsion W/O/W solution to evaporate the organic solvent, the microspheres are hardened.

The size of the microspheres may be 10 to 300 μm. The size of the biodegradable polymer microspheres may mean, for example, the particle size of the biodegradable polymer microspheres. If the size of the biodegradable polymer microspheres is less than 10 μm, it is difficult to encapsulate the primary W/O emulsion, and if the size of the microspheres exceeds 300 μm, it is not suitable for injection at high pressure. The method for producing biodegradable polymer microspheres according to the embodiment has a uniform particle size, so there is no need to use a powder machine, so the yield of microspheres of the desired size is 90% or more, and the size of the microspheres is changed by replacing membranes with different pore sizes. can be adjusted

S40 : Purify the microspheres through a filter and prepare a freeze-dried formulation for topical administration containing the purified microspheres and an excipient for dispersion.

The microspheres can be purified through a filter process. The remaining PVA is removed by washing with distilled water several times, and the remaining moisture is completely removed through freeze-drying.

The excipients include alginic acid and its salts, hyaluronic acid and its salts, carboxymethyl cellulose and its salts, dextran and its salts, collagen, and gelatin. ), and may include at least one of elastin (Elastin). The content of the excipient is 1 to 30% by weight. If it is out of the above range, it is difficult to evenly disperse the biodegradable polymer microspheres at an appropriate concentration outside the range that can control the content of the excipient.

The freeze-dried formulation for topical administration is prepared by mixing microspheres and excipients in water for injection, injecting them into a vial, and then freeze-drying them in the form of a cake.

2 is a conceptual diagram of an apparatus for manufacturing double-encapsulated biodegradable polymer microspheres according to an embodiment of the present invention. This device includes a primary W/O emulsification tank (1), a secondary O/W emulsification tank (2), a stirred tank for evaporating organic solvents (3), and a purification separation device (4).

The primary W/O emulsification tank 1 includes a membrane of small pores, and is equipped with a stirrer and two micropumps to control the flow rate. The flow rate of the micropump may be 0.01 mL/min to 1 mL/min, and the flow rate ratio of the aqueous solution mixed with the water-soluble drug and the organic solution in which the biodegradable polymer is dissolved may be 1:100 to 1:1 . If the flow rate of the micropump is less than 0.01 mL/min, the generation rate of the W/O emulsion is slowed, and if it exceeds 1 mL/min, the pressure increases and the size of the emulsion cannot be adjusted.

The secondary W/O emulsification tank 2 includes a large pore membrane, and is equipped with a stirrer and two micropumps to control the flow rate. The flow rate of the micropump may be 0.1 mL/min to 10 mL/min, and the flow rate ratio of the primary W/O emulsion and the aqueous solution containing the surfactant may be 1:100 to 1:1. If the flow rate of the micropump is less than 0.01 mL/min, the generation rate of the W/O/W emulsion is slow, and if it exceeds 10 mL/min, the pressure increases and the size of the emulsion cannot be adjusted.

The stirring tank 3 for evaporating the organic solvent may include a stirring device and a pressure reducing device to evaporate the solvent. The speed of the stirring device may be 20 rpm to 200 rpm, and when the stirring speed is less than 20 rpm, the particles are not evenly dispersed and the fine particles are agglomerated. The purification separation device 4 includes a reduced pressure filtration device, and fine spheres can be obtained through solid-liquid separation. The vacuum filtration device can use a filter method and a centrifugal separation device, and can remove used solvents, surfactants, and excipients through several washing processes, and excess moisture can be completely removed through freeze-drying.

Examples 1-1 to 5: Preparation of ascorbic acid encapsulated PLA microspheres

Concentrations shown in <Table 1> below were a solution of Abcorbic acid (manufacturer: Tokyo chemical industries, Japan) in 5% PVA (manufacturer: Merck, Germany) aqueous solution and a methylene chloride solution in which PLA polymer (manufacturer: Evonik, Germany) was dissolved. and prepare a 5% PVA aqueous solution.

Prepare a primary W/O emulsion by pouring 10 mL of ascorbic acid aqueous solution into a primary emulsification tank equipped with a hydrophobic membrane with 2 μm-sized pores and flowing it along with 100 mL of PLA polymer solution using a micropump. When the generated primary W/O emulsion is sufficiently collected in the secondary emulsification tank equipped with a hydrophilic membrane with 50 μm pores, the W/O/W emulsion is mixed with 1,000 mL of 5% PVA aqueous solution using a micropump. manufacture

When the W/O/W emulsion is completed and the reaction solution is collected in a stirring tank for evaporating the organic solvent, the organic solvent is removed by stirring at 150 rpm at room temperature for 12 hours. To completely remove moisture, lyophilization was performed to obtain microspheres.

Examples 1-6 to 9: Preparation of ascorbic acid-encapsulated PLGA microspheres

A solution of abcorbic acid (manufacturer: Tokyo chemical industries, Japan) in 5% PVA (manufacturer: Merck, Germany) aqueous solution and a polymer solution with a lactide-glycolide ratio of 75:25 (manufacturer: Cobion, The Netherlands) Prepare at the concentration of <Table 1> below, and prepare a 5% PVA aqueous solution.

Put 10 mL of ascorbic acid aqueous solution into a primary emulsification tank equipped with a hydrophobic membrane with 2 μm-sized pores and flow it along with 100 mL of PLGA polymer solution using a micropump to prepare a primary W/O emulsion. When the generated primary W/O emulsion is sufficiently collected in the secondary emulsification tank equipped with a hydrophilic membrane with 50 μm pores, the W/O/W emulsion is mixed with 1,000 mL of 5% PVA aqueous solution using a micropump. manufacture

When the W/O/W emulsion is completed and collected in a stirring tank for evaporating the organic solvent, the organic solvent is removed by stirring at 150 rpm at room temperature for 12 hours. For removal, lyophilization was performed to obtain a microsphere powder.

Examples 1-10-12: Preparation of PLGA microspheres encapsulated with goserelin acetate

A solution of goserelin acetate dissolved in 5% PVA (manufacturer: Merck, Germany) aqueous solution and a polymer (manufacturer: Cobion, Netherlands) solution with a ratio of lactide and glycolide of 75:25 were prepared at the concentrations shown in <Table 1> below. and prepare a 5% PVA aqueous solution.

Put 10 mL of goserelin acetate aqueous solution into a primary emulsification tank equipped with a hydrophobic membrane with 2 μm-sized pores and flow it along with 100 mL of PLA polymer solution using a micropump to prepare a primary W/O emulsion. When the generated primary W/O emulsion is sufficiently collected in the secondary emulsification tank equipped with a hydrophilic membrane with 30 μm pore size, the W/O/W emulsion is poured with 1,000 mL of 5% PVA aqueous solution using a micropump. manufacture

When the W/O/W emulsion is completed and the reaction solution is collected in a stirring tank for evaporating the organic solvent, the organic solvent is removed by stirring at 150 rpm at room temperature for 12 hours, and then washed repeatedly through a reduced pressure filter to remove PVA and remaining To completely remove moisture, lyophilization was performed to obtain microspheres.

Example type of drug polymer type Polymer solution concentration drug solution concentration Average particle size (μm) Example 1-1 Ascorbic acid PLA 5% 10% 65.4 Example 1-2 Ascorbic acid PLA 10% 10% 69.4 Examples 1-3 Ascorbic acid PLA 20% 10% 78.1 Examples 1-4 Ascorbic acid PLA 5% 20% 59.7 Examples 1-5 Ascorbic acid PLA 5% 10% 58.3 Examples 1-6 Ascorbic acid PLGA 5% 20% 59.9 Examples 1-7 Ascorbic acid PLGA 10% 10% 65.3 Examples 1-8 Ascorbic acid PLGA 5% 30% 67.1 Examples 1-9 Ascorbic acid PLGA 20% 20% 75.4 Examples 1-10 Goserelin PLGA 5% 10% 53.1 Examples 1-11 Goserelin PLGA 10% 10% 55.4 Examples 1-12 Goserelin PLGA 20% 10% 58.7

3 is an electron microscope photograph of microspheres of Example 1-1 prepared by the above method. It was confirmed that at a polymer concentration of 20% or less, uniform microspheres with an average particle size of about 60 μm were formed.

Examples 2-1 to 3: Preparation of microspheres encapsulated with dye components

Measure 0.01 g each of Allura red AC (red), tartrazine C (yellow), and brilliant Blue (blue) used as food coloring, and prepare it by dissolving it in 10 mL of 5% PVA aqueous solution. 10 g of PLA polymer (manufacturer: Evonik, Germany) was quantified, and a solution dissolved in 90 g of methylene chloride and 1 kg of 5% PVA aqueous solution were prepared.

Prepare a primary W/O emulsion by putting an aqueous solution containing each food coloring component into a primary emulsification tank equipped with a hydrophobic membrane with 2 μm-sized pores and flowing it along with the PLA polymer solution using a micropump. When the generated primary W/O emulsion is sufficiently collected in the secondary emulsification tank equipped with a hydrophilic membrane with 50 μm pore size, it is flowed with a 5% PVA aqueous solution using a micropump to prepare a W/O/W emulsion. .

4 is an electron micrograph of the dispersion of the microspheres and the microspheres encapsulated in the dye component by the above method. It can be confirmed that the pigment component was stably encapsulated in all three pigment-encapsulated microspheres.

Example 3: Preparation of porous microspheres

Prepare a solution dissolved in 90 g of methylene chloride by measuring 10 g of 5% PVA aqueous solution and PLA polymer (manufacturer: Evonik, Germany).

Prepare a primary W/O emulsion by putting a 5% PVA aqueous solution into a primary emulsification tank equipped with a hydrophobic membrane with 2 μm-sized pores and flowing it along with the PLA polymer solution using a micropump. When the generated primary W/O emulsion is sufficiently collected in the secondary emulsification tank equipped with a hydrophilic membrane with 50 μm pore size, it is flowed with a 5% PVA aqueous solution using a micropump to prepare a W/O/W emulsion. .

5 is an electron micrograph of the porous microspheres prepared by the above method. It can be confirmed that porous microspheres are formed when the drug is prepared by this research method only with an aqueous solution without encapsulating the drug.

Example 4: Preparation of a freeze-dried formulation for topical administration containing microspheres encapsulated with drugs

A freeze-dried vial formulation was prepared using the microspheres encapsulated in ascorbic acid and goserelin in Example 1. 75 mg of the microspheres prepared in Example 1 and 25 mg of carboxymethyl cellulose were dissolved in 2 mL of sterile water for injection, put into a vial, and then the mixture was frozen in a freezer and then freeze-dried.

6 is a photograph of a cross-section of the freeze-dried formulation in the form of a cake prepared by the above method measured with an electron microscope. It can be seen that the particles produced between the carboxymethyl cellulose foam.

Example 5: Analysis of ascorbic acid contained in polymer microspheres

For the content analysis of the ascorbic acid-encapsulated microspheres in Examples 1-1 to 9, high performance liquid chromatography was performed, and detailed experimental procedures and results are as follows.

10 mg of the prepared microspheres were dissolved in 2 mL of methylene chloride, pretreated, and injected into high-performance liquid chromatography, and measured using a UV absorbance detector.

For the mobile phase used for high performance liquid chromatography, a 40% (v/v) acetonitrile solution containing 0.1% (v/v) trifluoroacetic acid was flowed at a flow rate of 0.5 mL/min, and a C18 column (Inertsil ODS-3, Manufacturer: GL Science) was used.

Table 2 is a table showing the drug content and encapsulation rate according to the initial input amount of the drug compared to the polymer input amount. It can be seen that when the initial drug input is high, the encapsulation rate is lowered, and it can be confirmed that the encapsulation rate can be adjusted with a high content of water-soluble drugs depending on the conditions.

Example Initial input amount (% by weight) Drug content (wt%) Encapsulation rate (wt%) Example 1-1 20 16.4 82.0 Example 1-2 10 9.3 93.0 Examples 1-4 40 29.8 74.5 Examples 1-5 20 16.9 84.5 Examples 1-6 40 30.1 75.3 Examples 1-7 10 9.2 92.0 Examples 1-8 60 37.5 62.5

Example 6: Analysis of goserelin acetate contained in biodegradable polymer microspheres

For the content analysis of the microspheres encapsulated in goserelin acetate carried out in Examples 1-10 to 11, high-performance liquid chromatography was performed, and detailed experimental procedures and results are as follows.

10 mg of the prepared microspheres were dissolved in 2 mL of methylene chloride, pretreated, and injected into high-performance liquid chromatography, and measured using a UV absorbance detector.

The mobile phase used for high-performance liquid chromatography was water containing 0.1% (v/v) trifluoroacetic acid and acetonitrile containing 0.1% trifluoroacetic acid, and the solvent ratio was acetonitrile solution for 30 minutes. It was changed from 0% to 60%. The column used was Capcell pak C18 (inner diameter 2.0, length 15 cm), and the flow rate of the mobile phase was 0.2 mL/min.

Table 3 is a table showing the drug content and encapsulation rate according to the initial dosage of the drug compared to the polymer input. It can be confirmed that when the initial drug input is high, the encapsulation rate is lowered, and it can be confirmed that the encapsulation rate can be adjusted with a high content of the peptide drug depending on the conditions.

Example Initial input amount (% by weight) Drug content (wt%) Encapsulation rate (wt%) Examples 1-10 20 14.65 73.3 Examples 1-11 10 8.39 83.9 Examples 1-12 5 4.53 90.6

Claims (12)

(1) making a W/O emulsion using a hydrophobic membrane with an aqueous solution in which a surfactant and a water-soluble physiologically active substance are dissolved and an organic solution in which a biodegradable polymer is dissolved in an organic solvent;
(2) preparing an O/W emulsion using an aqueous solution containing a surfactant and a hydrophilic membrane for the prepared W/O emulsion;
(3) removing the organic solvent from the W/O/W solution and curing to produce microspheres; and
(4) purifying the microspheres, and preparing a freeze-dried formulation for topical administration containing the purified microspheres and an excipient for dispersion;
In this case, the pores of the hydrophobic membrane are 1 to 3 μm, and the pores of the hydrophilic membrane are 20 to 60 μm,
The water-soluble physiologically active substance of step (1) is a water-soluble vitamin,
The surfactant in steps (1) and (2) is polyvinyl alcohol,
The biodegradable polymer of step (1) is selected from polylactic acid (PLA) and polylactic acid-glycolic acid (PLGA), and the average molecular weight of the polymer is 10,000 to 200,000,
The organic solvent of step (1) is methylene chloride, characterized in that the content of the biodegradable polymer dissolved in the organic solvent is 1 to 20% by weight,
A method for preparing double-encapsulated biodegradable polymer microspheres for topical administration. delete delete delete delete delete delete The method of claim 1,
The method for producing double-encapsulated biodegradable polymer microspheres for topical administration, characterized in that the size of the microspheres in step (3) is 10 to 300 μm. 9. The method of claim 8,
The dispersing excipient of step (4) is carboxymethyl cellulose and its salt, alginic acid and its salt, hyaluronic acid and its salt, dextran and its salt, collagen (collagen), gelatin (Gelatin), and elastin (Elastin) containing at least one, the content of the excipient for dispersion is 1 to 30% by weight of the method for producing double-encapsulated biodegradable polymer microspheres for topical administration, characterized in that. delete delete delete

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