Biodegradable polymer fine particle for filler, freeze-dried body including the same, manufacturing method thereof, and filler injection including freeze-dried body

1 . A manufacturing method of a freeze-dried body for a filler, the manufacturing method comprising:

preparing a biodegradable polymer microparticle for a filler having an average particle diameter of 20-50 μm, wherein the biodegradable polymer microparticle is a polydioxanone microparticle;

surface-treating the biodegradable polymer microparticle with plasma using discharge or base to manufacture a surface-treated biodegradable polymer microparticle, wherein the surface-treated biodegradable polymer microparticle is a polydioxanone microparticle which has a carboxyl group on a surface thereof;

dissolving the surface-treated biodegradable polymer microparticle, a biocompatible carrier, and distilled water to obtain a mixed solution; and

freeze-drying the mixed solution to obtain a freeze-dried body,

wherein the surface-treating with plasma using discharge comprises:

fluidizing the biodegradable polymer microparticle through an inner pipe within a plasma reaction device,

injecting 400 to 600 mL/min of air into the inner pipe through a gas supply unit in the plasma reaction device, and

directly applying 300 Hz to 500 Hz of alternating current to an electrode to which a power supply unit is directly connected so that plasma-treated air is fluidized together with and comes into contact with the biodegradable polymer microparticle, and

wherein the surface-treating with base is performed through adding and treating the biodegradable polymer microparticle to 0.1 to 5% by weight of a sodium hydroxide solution to obtain microparticles, and washing and vacuum-drying the microparticles, wherein a content of sodium hydroxide is 0.1 to 5 parts by weight based on 100 parts by weight of the biodegradable polymer microparticles.

2 . The manufacturing method according to claim 1 , wherein the biodegradable polymer microparticle is manufactured through: providing a first composition containing organic solvent miscible with water, and polydioxanone; providing a second composition containing surfactant and water; preparing mixture by mixing the first composition and the second composition; stirring the mixture to prepare a third composition containing polymer microparticles; separating the polymer microparticles from the third composition; and sorting polymer microparticles, of which the average particle diameter is 20 to 50 μm, from the separated polymer microparticles.

3 . The manufacturing method according to claim 2 , wherein the first composition is free of surfactant, and the second composition contains surfactant.

4 . The manufacturing method according to claim 2 , wherein the organic solvent contained in the first composition is completely or partially mixed with water and does not form a separate phase differentiated from water.

5 . The manufacturing method according to claim 1 , wherein the surface-treated biodegradable polymer microparticle has an average particle diameter (D50) of 20 to 50 μm,

wherein the surface-treated biodegradable polymer microparticle is a plasma surface-treated product or a base surface-treated product using discharge of the biodegradable polymer microparticle,

wherein a content of the biocompatible carrier is 1 to 5 parts by weight based on 100 parts by weight of the freeze-dried body,

wherein the biocompatible carrier is sodium carboxymethyl cellulose, and a moisture content in the freeze-dried body is 0.5 to 1.0% by weight,

wherein a powder-water contact angle value to the surface-treated biodegradable polymer microparticle is 35.1 to 35.7°,

wherein the base surface-treated product of the biodegradable polymer microparticle is a product obtained through: adding 0.1 to 5% by weight of a sodium hydroxide solution to the biodegradable polymer microparticle for a filler, and stirring it for 30 seconds to 300 seconds; and washing and vacuum-drying the product obtained through the stirring, wherein the content of sodium hydroxide is 1 to 5 parts by weight based on 100 parts by weight of the biodegradable polymer microparticle for a filler, and

wherein the plasma surface-treated product is a product obtained through: applying voltage to the biodegradable polymer microparticle for a filler to induce discharge; and performing a discharge treatment of the biodegradable polymer microparticle,

wherein the discharge treatment of the biodegradable polymer microparticle comprises:

fluidizing the biodegradable polymer microparticle through an inner pipe within a plasma reaction device,

injecting 400 to 600 mL/min of air into the inner pipe through a gas supply unit in the plasma reaction device;

directly applying 300 Hz to 500 Hz of alternating current to an electrode to which a power supply unit is directly connected to obtain plasma-treated air; and

making the plasma-treated air fluidized together with and come into contact with the biodegradable polymer microparticle.

6 . The manufacturing method according to claim 1 , wherein a 10% cumulative diameter (D10) of the surface-treated biodegradable polymer microparticle is 10 to 20 μm, and a 90% cumulative diameter (D90) of the surface-treated biodegradable polymer microparticle is 60 to 70 μm.

7 . The manufacturing method according to claim 6 , wherein the surface-treated biodegradable polymer microparticle satisfies Formula 1 in connection with the 10% cumulative diameter (D10), the average particle diameter (D50), and the 90% cumulative diameter (D90),

0.8≤( D 90 −D 10 )/ D 50 ≤3.5  [Formula 1]

8 . The manufacturing method according to claim 1 , wherein the number average molecular weight (Mn) of the biodegradable polymer microparticle is 50,000 to 500,000 Daltons.