KR102047984B1 - Dermal filler of porous and homogeneous polycaprolactone microspheres and method for preparing the same - Google Patents

Abstract

The present invention relates to a polycaprolactone microsphere, a filler comprising the same and a method for preparing the same, having a uniform size distribution of porous and having a mean particle size of 10 to 100 μm. As soon as the volume is expressed immediately after the procedure, the injection dose is good and the maintenance period is long, thereby providing a molding filler having excellent repair or volume expansion and wrinkle improvement characteristics of soft tissues such as cheeks, chest, nose, lips and hips. can do.

Description

Dermal filler of porous and homogeneous polycaprolactone microspheres and method for preparing the same

The present invention relates to a porous uniform polycaprolactone microsphere filler and a method for producing the same, and more particularly, to a method for producing a polycaprolactone microsphere filler by an emulsion method using calcium chloride and a uniform porous membrane, the production method It relates to a porous uniform polycaprolactone microspheres produced by the filler and a filler comprising the same.

Biodegradable polymers, such as polycaprolactone and polylactic acid, are manufactured in the form of microspheres or microparticles, and inserted into specific areas of the skin to expand soft tissues to be used as dermal fillers for wrinkle improvement or contour correction. Used.

Dermal filler is an injection type medical device that supplements skin tissue by injecting a safe material into the facial dermis layer to improve wrinkles and find volume in aesthetic appearance. Botulinum toxin (Botox), autologous fat transplant, silencing, micro It is used in so-called anti-aging procedures, including needles, laser therapy, and dermabrasion.

The first-generation dermal filler developed for the first time is an animal-derived collagen filler, which is rarely used in recent years due to the short duration of the effect after the procedure (2-4 months) and the need for skin hypersensitivity test one month before the procedure.

The second generation of dermal fillers are hyaluronic acid fillers, which have a longer duration than collagen fillers and are composed of polysaccharides similar to the components of the human body. It is the most used filler at present. In particular, hyaluronic acid is easy to be treated and removed, excellent in viscoelasticity (viscoelasticity), it is very suitable as a raw material of the filler for the skin to maintain the moisture of the skin and maintain the volume and elasticity of the skin. Recently, research has been actively conducted to extend the duration by inducing cross-linking of hyaluronic acid to increase particle size and molecular weight, but every 6-12 months because the retention time is relatively short (6-12 months). There is a hassle that needs to be repeated.

The third generation filler is a synthetic polymer filler such as polylactic acid (PLA) or polycaprolactone (PCL), which is degraded very slowly in the human body, so it is evaluated as a semi-permanent filler compared to collagen and hyaluronic acid fillers, which are absorbent fillers. It is used. In particular, polycaprolactone is 100% absorbed by the human body and is a safe ingredient, and it is slower to be absorbed than polylactic acid after implantation into the skin, and promotes the production of collagen, so that the effect lasts for 1 to 4 years with a soft feeling tissue without foreign substances. There is an advantage. Polycaprolactone fillers are microspheres-type fillers that should be suspended in gel carriers such as carboxymethylcellulose (CMC), and are often clogged when injected into the skin depending on the average particle size or size distribution of the microspheres. It should be replaced with In addition, a temporary decrease in volume occurs for 3-4 days to 4 weeks after injection into the skin, and recovers only after 6-8 weeks, and thus the satisfaction of the procedure is lower than that of the hyaluronic acid filler, which shows an immediate effect after the procedure.

Therefore, while the effect of the filler treatment is maintained for a long time, it is required to develop a new polycaprolactone microparticle filler that shows an immediate treatment effect like a hyaluronic acid filler and does not block when injected with a thin needle.

The present invention has been made to solve the above-mentioned conventional technical problems, while the long-term maintenance period when applied to the living body, showing the effect of increasing the volume of the treatment site immediately after the procedure, such as hyaluronic acid filler, the injection capacity It is an object of the present invention to provide a uniform polycaprolactone microsphere filler of improved porosity and a method of making the same.

As a means for solving the above problems,

The present invention provides a porous uniform polycaprolactone microspheres having an average particle size of 10 to 100 μm, a tap density of 0.5 g / cc or less and a span value of 1.0 or less.

According to another aspect of the present invention, (a) dissolving polycaprolactone in a first solvent and calcium chloride in a second solvent to uniformly mix the two solutions to prepare a single solution to prepare a dispersed phase; (b) passing the dispersed phase through a membrane with uniform pores to an aqueous solution containing a surfactant (continuous phase) to produce an emulsion; (c) extracting and evaporating the organic solvent from the dispersed phase in the prepared emulsion into a continuous phase to form microspheres; And (d) recovering the microspheres from the continuous phase of step (c), a method for producing porous uniform polycaprolactone microspheres.

According to another aspect of the invention, the porous uniform polycaprolactone microspheres of the present invention; And pharmaceutically acceptable carriers for injection and polycaprolactone microspheres.

The filler including the porous uniform polycaprolactone microspheres according to the present invention, when applied to a living body, may exhibit an effect of good injection dose and long maintenance period, even though the volume is expressed immediately after the procedure, such as a hyaluronic acid filler.

Figure 1a is a photograph taken with an electron microscope the shape of the polycaprolactone microspheres prepared according to Example 1. As can be seen in the picture, it can be seen that the microspheres are made of porous microspheres having a spherical shape on the surface.
Figure 1b is a photograph confirming the cut surface of the polycaprolactone microspheres prepared according to Example 1, it can be seen that a number of pores are formed in the microspheres.
Figure 1c is a photograph taken with an electron microscope the shape of the polycaprolactone microspheres prepared according to Example 1-2 using 10% (w / w) calcium chloride in the preparation of the dispersed phase. As can be seen in the picture, it can be seen that as the amount of calcium chloride used increases, the pores on the surface of the microspheres also increase relatively.
2 is a photograph taken with an electron microscope of the shape of the polycaprolactone microspheres prepared without using calcium chloride according to Comparative Example 1. As can be seen in the photograph, the resulting microspheres have a very smooth surface inside, and it can be seen that they do not have a porous structure.

Hereinafter, the present invention will be described in more detail.

The polycaprolactone microspheres of the present invention are prepared using polycaprolactone having an intrinsic viscosity of 0.16 to 1.90 dL / g of biodegradable polymer. The intrinsic viscosity of polycaprolactone used in the present invention refers to those measured in chloroform at 25 ° C. using an Ubbelohde viscometer. If the intrinsic viscosity of polycaprolactone is less than 0.16 dL / g, the molecular weight of the polymer is insufficient, and the volume maintenance period of the filler site is too short, and if the intrinsic viscosity exceeds 1.90 dL / g, Due to the high viscosity, there is a problem in that an excess amount of the solvent is used, and it is difficult to produce reproducible microspheres.

Examples of the polycaprolactone polymers include Resormer C209, C212 and C217 from Evonik, Purasorb PC02, PC04, PC08, PC12, and PC17 from Corbion, and the like. A combination of these.

Polycaprolactone microspheres according to the present invention have an average particle size of 10 μm or more and 100 μm or less, for example, 10 to 30 μm, 10 to 50 μm, or 10 to 100 μm, 20 to 50 μm, 30 to 60 μm, Or 40 to 70 μm. The term "average particle size" used in the present invention refers to a particle size corresponding to 50% of the volume% in the particle size distribution curve, which means a median diameter and is expressed as D50 or D (v, 0.5).

If the average particle size of the polycaprolactone microspheres is less than 10 μm, they may be detected by macrophages when administered in vivo.If the average size of the polycaprolactone microspheres is greater than 100 μm, the injection capacity may be reduced when the syringe is injected into the syringe. It is not desirable to grow big.

The polycaprolactone microspheres of the present invention are characterized by having a uniform particle distribution. The microspheres having a uniform particle distribution have a smaller variation in the residual amount of the syringe and needle during injection and less needle clogging than the non-uniform microspheres. It is preferable that the size distribution or span value of the polycaprolactone microspheres of the present invention is 1.0 or less. More preferably, the size distribution is 0.8 or less. The size distribution or span value used in the present invention is an index indicating the uniformity of the particle size of the microspheres, and the size distribution (Span value) = (Dv0.9-Dv0.1) /Dv0.5 It means the value obtained by. Where Dv0.1 is the particle size corresponding to 10% of the volume% in the particle size distribution curve of the microspheres, Dv0.5 is the particle size corresponding to 50% of the volume% in the particle size distribution curve of the microspheres, and Dv0.9 is the particle size distribution of the microspheres. The particle size corresponds to 10% of the volume% in the curve. Polycaprolactone microspheres according to the present invention is characterized in that the injection capacity is improved by reducing the needle clogging to exhibit a uniform size distribution while showing a particle size of 10 μm or more, 100 μm or less.

Polycaprolactone microspheres of the present invention is characterized by having a tapped density of 0.5 g / cc or less as a parameter representing porosity. For example 0.1 g / cc to 0.2 g / cc, 0.1 g / cc to 0.3 g / cc, 0.1 g / cc to 0.4 g / cc, 0.1 g / cc to 0.5 g / cc, 0.2 g / cc to 0.3 g / cc, 0.2 g / cc to 0.4 g / cc, 0.2 g / cc to 0.5 g / cc, 0.3 g / cc to 0.4 g / cc, 0.3 g / cc to 0.5 g / cc or 0.4 g / cc to 0.5 g It can represent a tap density of / cc. Tap density is a certain amount of microspheres are put in a tap density measuring instrument having a certain volume, and tapping (tapping) at a constant speed and a certain number of times. The mass of the microspheres per unit volume The measured value. If the polycaprolactone microspheres of the present invention exhibit a tap density of 0.5 g / cc or more, there is a possibility that the volume of the polycaprolactone microspheres may decrease at the beginning of the injection because the lack of porosity may result in insufficient water penetration. When showing a tap density of cc or less, the porosity is too high to increase the volume of the microspheres, there is a disadvantage that the suspension is not made with the appropriate amount of the suspension used in the filler.

The porous polycaprolactone microspheres of the present invention increase the inflow of water into the microspheres at the beginning of the injection by the porosity of the microspheres when injected in vivo, thereby reducing the initial volume reduction effect of the polycaprolactone microspheres. In contrast, in the case of nonporous polycaprolactone microspheres, there is no porosity connecting from the surface of the microspheres so that the inflow of the microspheres is relatively limited, and the area where water directly contacts the microspheres is relatively small, so that the moisture content is reduced and the initial volume is reduced. Decrease occurs.

The porosity of such microspheres is a characteristic obtained by using calcium chloride, which will be described in detail below.

Polycaprolactone microspheres according to the present invention is collected by dividing 1 g in a 1.5 mL tube with a syringe equipped with a 26 gauge needle and calculated as the dry weight of the recovered microspheres, at least 80% (w / w), Preferably, 85 to 99% (w / w) of microspheres is recovered. Polycaprolactone microspheres according to the present invention exhibits a uniform size distribution while showing a particle size of 10 μm or more and 100 μm or less, thereby exhibiting such a recovery rate. As a result, the polycaprolactone microspheres according to the present invention can be administered in a smaller and more accurate amount when injected, and the injection ability is improved by reducing needle blockage.

Polycaprolactone microspheres according to the present invention can be prepared using the "solvent extraction and evaporation method", but the production method is not limited to the method of providing the fine particles to exhibit the above-described particle diameter, size distribution and porosity.

As a specific example of the method for producing polycaprolactone microspheres according to the present invention, (a) polycaprolactone is dissolved in a first solvent and calcium chloride is dissolved in a second solvent to prepare respective solutions. Preparing a dispersed phase by uniformly mixing the two solutions into a single solution, (b) passing the dispersed phase through a membrane having a hole of uniform size to an aqueous solution containing a surfactant (continuous phase) to prepare an emulsion. Step (c) extracting and evaporating the organic solvent in a continuous phase from the dispersed phase in the emulsion prepared in step (b) to form microspheres, and (d) recovering the microspheres from the continuous phase of step (c) Preparing a porous uniform polycaprolactone microspheres.

The intrinsic viscosity of the polycaprolactone in the step (a) is preferably in the range of 0.16 ~ 1.90 dL / g.

It is preferable that the first solvent used to dissolve the polycaprolactone in the step (a) has a property of being incompatible with water. By utilizing the property of being incompatible with water of the organic solvent, the emulsion can be formed by homogeneously mixing and dispersing the dispersed phase in an aqueous solution (continuous phase) containing a surfactant in step (b) described later. The kind of the solvent for dissolving such polycaprolactone is not particularly limited, but may be preferably selected from the group consisting of dichloromethane, chloroform, ethyl acetate, methyl ethyl ketone, and a mixed solvent thereof, more preferably dichloromethane. Methane, ethyl acetate or a mixed solvent thereof can be used.

Calcium chloride in the step (a) is a material that creates porosity in the produced polycaprolactone microspheres to have a porosity, the second solvent for dissolving calcium chloride can be used without limitation, so long as it can dissolve calcium chloride, For example, calcium chloride is preferably dissolved in methyl alcohol, ethyl alcohol, or a mixed solvent thereof.

The calcium chloride is preferably 0.01 to 15% by weight based on the total weight of the dispersed phase solutes (ie, the sum of polycaprolactone and calcium chloride). If calcium chloride is used at less than 0.01% by weight, the porosity of the microspheres is not sufficiently secured. If calcium chloride is used at more than 15% by weight, the second solvent used to dissolve the calcium chloride should be used in excess. The solvent has the disadvantage that it is difficult to produce a normal spherical microspheres.

In step (a), polycaprolactone and calcium chloride solution are mixed to form a uniform mixed solution to prepare a dispersed phase. The polycaprolactone and calcium chloride mixed solution is preferably dissolved homogeneously. For example, when methylene chloride is used as the polycaprolactone solvent and methyl alcohol is used as the calcium chloride solvent, the amount of methyl alcohol is preferably 5 to 50% by weight of methylene chloride. If the amount of methyl alcohol is less than 5% by weight, calcium chloride is more likely to be precipitated due to the solubility due to methylene chloride, and if it is more than 50% by weight, polycaprolactone is likely to be precipitated by methyl alcohol, which is not preferable. .

The dispersed phase prepared in step (a) is passed through a membrane with uniformly sized micropores to a continuous phase containing surfactant to form an emulsion. The micropores of the membrane are preferably 5-50 μm in size.

The type of surfactant used in step (b) is not particularly limited, and any type of surfactant can be used as long as it can help to form an emulsion of stable droplets in the continuous phase. The surfactant is preferably a group consisting of methyl cellulose, polyvinylpyrrolidone, carboxymethyl cellulose, lecithin, gelatin, polyvinyl alcohol, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene castor oil derivative, and mixtures thereof It may be selected from, and most preferably polyvinyl alcohol can be used.

In step (b), the content of the surfactant in the continuous phase comprising the surfactant is from 0.01 w / v% to 20 w / v%, preferably 0.1 w, based on the total volume of the continuous phase comprising the surfactant. / v% to 5 w / v%. When the content of the surfactant is less than 0.01 w / v%, no dispersed phase or emulsion in the form of droplets may be formed in the continuous phase, and when the content of the surfactant is more than 20 w / v%, the excess surfactant Due to this, after the fine particles are formed in the continuous phase, it may be difficult to remove the surfactant.

In step (c), the emulsion comprising the dispersed phase in the form of droplets and the continuous phase containing the surfactant is held or stirred at a temperature below the boiling point of the organic solvent for a period of time, for example from 2 to 48 hours, The organic solvent can be extracted in a continuous phase from the polycaprolactone-calcium chloride solution in the form of droplets in the dispersed phase. Some of the organic solvent extracted in the continuous phase may be evaporated from the continuous phase surface. As the organic solvent is removed from the solution in the form of droplets, the dispersed phase in the form of droplets can solidify to form microspheres. Since calcium chloride is well soluble in water, most of it comes out in a continuous phase with an organic solvent. As a result, when the microspheres solidify, they form pores, and porous microspheres are formed, thus forming a suspension containing microspheres (microsphere suspension). Will be obtained.

In the step (c), the temperature of the continuous phase may be heated for a predetermined time in order to further efficiently remove the organic solvent. For example, but not limited to, within 48 hours, preferably 1 to 36 hours, more preferably while maintaining the temperature at 5 to 39.6 ° C, preferably 10 to 35 ° C, more preferably 15 to 30 ° C The organic solvent can be removed by stirring for about 3 to 24 hours .

In the step (d), the method for recovering polycaprolactone microspheres can be carried out using a variety of known techniques, for example, can be used a method such as filtration or centrifugation.

Between step (c) and step (d), the remaining surfactant can be removed by filtration and washing, and filtered again to recover the microspheres.

The washing step to remove the remaining surfactant can typically be carried out with water, which washing step can be repeated several times.

According to another aspect of the invention, the porous uniform polycaprolactone microspheres of the present invention; And a pharmaceutically acceptable aqueous carrier and polycaprolactone microspheres.

As the pharmaceutically acceptable aqueous carrier, for example, an aqueous solution for injection selected from the group consisting of purified water, saline and phosphate buffer may be used. In addition, the filler is a cellulose derivative such as carboxymethyl cellulose (CMC), hydroxypropyl methyl cellulose (HPMC), hyaluronic acid, lidocaine, polydeoxyribonucleotide, together with polycaprolactone microspheres and an aqueous carrier, if necessary Solutes such as (PDRN) and polynucleotides (PN), and one or more lubricants such as glycerin, but is not limited thereto.

In one embodiment, the content of each component included in the filler comprising the polycaprolactone microspheres of the present invention, based on the total 100% by weight of the filler formulation, 2-50% by weight of the polycaprolactone microspheres, pharmaceutically acceptable Possible aqueous carriers may be 15 to 99.9 weight percent, solute 0.1 to 5 weight percent, lubricant 0 to 48 weight percent, but are not limited thereto. When hyaluronic acid is added as a solute, hyaluronic acid having a crosslinking rate of 0 to 5% can be used.

The filler containing the polycaprolactone microspheres according to the present invention shows excellent characteristics with good injection dose and long retention period, even immediately after the procedure, at the volume of the procedure, which is very useful for cosmetic or therapeutic purposes. Can be.

As a specific example, a filler comprising such polycaprolactone microspheres may include filling biological tissues, improving wrinkles through filling wrinkles, remodeling of the face, or lips, nose, buttocks. It may be used to repair or increase the volume of soft tissues such as, cheeks or chest. The filler comprising the polycaprolactone microspheres may be administered in a dosage form suitable for this use, and may preferably be an injection.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are merely to illustrate the invention, but the content of the present invention is not limited by the following examples.

EXAMPLE

Example 1: 1% (w / w) CaCl ₂ Polycaprolactone Microspheres Using

The dispersed phase is 1.98 g of biocompatible polymer Purasorb PC 04 (Corbion, Netherlands) and 0.02 g of calcium chloride (Tr Fisher Fisher, USA), respectively, 7.92 g of dichloromethane (JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) After mixing with 0.5 mL of the melt was prepared by mixing the two solutions. The continuous phase was an aqueous solution of 1 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 1200 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 10 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 1-1: 5% (w / w) CaCl ₂ Polycaprolactone Microspheres Using

The dispersed phase consists of 1.9 g of Purasorb PC 04, Corbion, Netherlands, and 0.1 g of calcium chloride, Thermo Fisher Scientific, USA, 7.6 g of dichloromethane (JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.9 mL and then prepared by mixing the two solutions. The continuous phase was an aqueous solution of 1 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 1100 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 10 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 1-2: 10% (w / w) CaCl ₂ Polycaprolactone Microspheres Using

The dispersed phase was 1.8 g of Purasorb PC 04 (manufactured by Corbion, Netherlands) and 0.2 g of calcium chloride (manufactured by Thermo Fisher Scientific, USA), 7.2 g of dichloromethane (manufactured by JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 1.4 mL and prepared by mixing the two solutions. The continuous phase was an aqueous solution of 1 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 1000 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 10 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 2 Preparation of Porous Polycaprolactone Microspheres with an Average Particle Size Control

The dispersed phase is 1.94 g of biocompatible polymer Purasorb PC 04 (Corbion, Netherlands) and 0.06 g of calcium chloride (Tr. Fisher Scientific, USA), respectively, 7.76 g of dichloromethane (JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.7 mL and then prepared by mixing the two solutions. As the continuous phase, 2 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s) aqueous solution was used, while 1200 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 5 μm, and the prepared dispersed phase was injected. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 2-1: Preparation of porous polycaprolactone microspheres with average particle size

The dispersed phase is 1.94 g of biocompatible polymer Purasorb PC 04 (Corbion, Netherlands) and 0.06 g of calcium chloride (Tr. Fisher Scientific, USA), respectively, 7.76 g of dichloromethane (JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.7 mL and then prepared by mixing the two solutions. For continuous phase, 5 w / v% polyvinyl alcohol (viscosity: 4.8 ~ 5.8 mPa · s) aqueous solution was used, while 1200 mL of continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 30 μm, and the prepared dispersed phase was injected. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 2-2 Preparation of Porous Polycaprolactone Microspheres with an Average Particle Size Controlled

The dispersed phase is 1.94 g of biocompatible polymer Purasorb PC 04 (Corbion, Netherlands) and 0.06 g of calcium chloride (Tr. Fisher Scientific, USA), respectively, 7.76 g of dichloromethane (JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.7 mL and then prepared by mixing the two solutions. The continuous phase was an aqueous solution of 3 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 1200 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 40 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 3: Preparation of Porous Polycaprolactone Microspheres

The dispersed phase is 1.94 g of biocompatible polymer Purasorb PC 02 (manufactured by Corbion, Netherlands) and 0.06 g of calcium chloride (manufactured by Thermo Fisher Scientific, USA), respectively, 5.88 g of dichloromethane (manufactured by JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.6 mL and then prepared by mixing the two solutions. The continuous phase was an aqueous solution of 1 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 900 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 10 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 3-1 Preparation of Porous Polycaprolactone Microspheres

The disperse phase consists of 10.78 g of dichloromethane (manufactured by JT Baker, USA) and 1.94 g of Purasorb PC 12 (manufactured by Corbion, Netherlands) and 0.06 g of calcium chloride (manufactured by Thermo Fisher Scientific, USA), respectively. Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.7 mL and then prepared by mixing the two solutions. For continuous phase, 5 w / v% polyvinyl alcohol (viscosity: 4.8 ~ 5.8 mPa · s) aqueous solution was used, and 1600 mL of continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 10 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 3-2 Preparation of Porous Polycaprolactone Microspheres

The disperse phase consists of 16.17 g of dichloromethane (manufacturer: JT Baker, USA) and 1.94 g of biocompatible polymer Purasorb PC 17 (Corbion, Netherlands) and 0.06 g of calcium chloride (Tr. Fisher Scientific, USA), respectively. Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.7 mL and then prepared by mixing the two solutions. The continuous phase was used as an aqueous solution of 5 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 2500 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 10 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Example 4 Preparation of Polycaprolactone Microsphere Filler Using Carboxymethylcellulose as Solute

Polycaprolactone microsphere filler was prepared by mixing the microspheres after preparing a solution for microsphere suspension. 2 g of carboxymethyl cellulose (manufactured by Ashland, USA) is placed in a 75 ° C. phosphate buffer solution, dissolved by stirring at 100 rpm for 3 hours, and cooled. When the solution temperature reached 25 ° C, 18 g of glycerin was added and the polycaprolactone microspheres were finally mixed with 30% (w / w) to complete the polycaprolactone microsphere filler.

Example 4-1 Preparation of polycaprolactone microsphere filler using hyaluronic acid as a solute

Polycaprolactone microsphere filler was prepared by mixing the microspheres after preparing a solution for microsphere suspension. 1 g of hyaluronic acid (manufactured by Bloomage Freda Biopharm, China) is dissolved in 55 ° C phosphate buffer and allowed to cool. When the solution temperature reached 25 ° C, 18 g of glycerin was added and the polycaprolactone microspheres were finally mixed with 30% (w / w) to complete the polycaprolactone microsphere filler.

Comparative Example 1: Preparation of Nonporous Polycaprolactone Microspheres

The dispersed phase was prepared by mixing 2 g of biocompatible polymer Purasorb PC 04 (Corbion, Netherlands) with 6.4 g of dichloromethane (J.T Baker, USA). The continuous phase was an aqueous solution of 1 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 1500 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 10 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at a speed of 150 rpm, and the membrane emulsifier and the preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After the removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol, and the microspheres were lyophilized.

Comparative Example 1-1: 20% (w / w) CaCl ₂ Polycaprolactone Microspheres Using

The disperse phase consists of 1.6 g of Purasorb PC 04, Corbion, Netherlands, and 0.4 g of calcium chloride, Thermo Fisher Scientific, USA, 6.4 g of dichloromethane (JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 2.5 mL and prepared by mixing the two solutions. The continuous phase was an aqueous solution of 1 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 950 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 10 μm, and the prepared dispersed phase was injected. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at 150 rpm, and the membrane emulsifier and preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Comparative Example 2: Preparation of polycaprolactone microspheres with an average particle size adjusted

The dispersed phase is 1.94 g of biocompatible polymer Purasorb PC 04 (Corbion, Netherlands) and 0.06 g of calcium chloride (Tr. Fisher Scientific, USA), respectively, 7.76 g of dichloromethane (JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.7 mL and then prepared by mixing the two solutions. The continuous phase was used as an aqueous solution of 5 w / v% polyvinyl alcohol (viscosity: 4.8 to 5.8 mPa · s), and 1200 mL of the continuous phase was connected to an emulsifier equipped with a porous membrane having a diameter of 50 μm. Microspheres were prepared. The microsphere suspension was added to the preparation vessel and stirred at 150 rpm, and the membrane emulsifier and preparation vessel temperature were maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Comparative Example 2-1: Preparation of polycaprolactone microspheres using a high speed stirrer

The dispersed phase is 1.94 g of biocompatible polymer Purasorb PC 04 (Corbion, Netherlands) and 0.06 g of calcium chloride (Tr. Fisher Scientific, USA), respectively, 7.76 g of dichloromethane (JT Baker, USA) and methyl alcohol ( Manufacturer: Sigma Aldrich, USA) The mixture was dissolved in 0.7 mL and then prepared by mixing the two solutions. For continuous phase, 5 w / v% polyvinyl alcohol (viscosity: 4.8 ~ 5.8 mPa · s) aqueous solution was used, and 1200 mL of continuous phase was added to the preparation container, and the dispersed phase was stirred 7 mL / min while stirring the equipped high speed mixer at 1000 rpm. Injected at a flow rate. The microsphere suspension was stirred at 150 rpm and the preparation vessel temperature was maintained at 25 ° C.

Upon completion of the dispersed phase injection, the microsphere suspension was stirred at 150 rpm at 25 ° C. for 24 hours to remove the organic solvent. After removal of the organic solvent, the microsphere suspension was repeatedly washed several times with distilled water to remove residual polyvinyl alcohol and calcium chloride, and the microspheres were lyophilized.

Experimental Example 1: Morphological Analysis of Microspheres by Electron Microscopy

This experiment was carried out to analyze the morphological characteristics of the prepared microspheres, the detailed experimental procedure is as follows. 5 mg of microspheres were placed on an aluminum stub with carbon tape and coated with platinum using ION-COATER (COXEM, South Korea). An aluminum stub was mounted on a scanning electron microscope (COXEM EM-30, Korea) and the microsphere morphological characteristics were observed at an acceleration voltage of 15 kV.

As shown in Figure 1a in the case of Example 1 was confirmed that the pores were formed in a small proportion on the surface of the microspheres prepared using 1% (w / w) calcium chloride. As shown in FIG. 1C, it was confirmed that the porosity of the surface of the microspheres was relatively increased as the amount of calcium chloride used increased, and the amount of pore formation could be controlled through the amount of calcium chloride.

In addition, the microspheres were physically cut to confirm the microsphere cross section of Example 1. Specifically, the microspheres were placed in a petri dish and randomly cut into several overlapping razor blades. The microspheres were attached to an aluminum stub and the cross section was observed as described above. As shown in FIG. 1B, it was confirmed that pores were randomly formed inside the microspheres of Example 1, which had a relatively smooth surface.

As shown in FIG. 2, Comparative Example 1 was an image of polycaprolactone microspheres prepared without calcium chloride, and the microspheres confirmed a smooth surface, and thus the pores of the microspheres were not formed without using calcium chloride.

Experimental Example 2: Grain Size Analysis by Laser Diffraction

This experiment was carried out to quantitatively measure the average particle size, distribution and uniformity of the prepared microspheres. The experimental procedure is as follows.

50 mg of microspheres were mixed with 1 mL ultrapure water and mixed with a vortex mixer for 20 seconds, and then placed in an ultrasonic generator for 1 minute and dispersed. The microsphere dispersion was placed in a particle size analyzer (Microtrac Bluewave, Japan) and measured for 20 seconds. As an index of particle size uniformity, the span value was calculated by Equation 1 below.

[Equation 1]

Span Value = (D _{v, 0.9} -D _{v, 0.1} ) / D _{v, 0.5}

D _{v, 0.5} (μm) Span Value Example 1 34.5 0.61 Example 1-1 35.2 0.64 Example 1-2 34.9 0.75 Example 2 15.1 0.56 Example 2-1 56.8 0.60 Example 2-2 98.7 0.62 Example 3 36.3 0.61 Example 3-1 35.8 0.75 Example 3-2 36.7 0.82 Comparative Example 1 35.5 0.57 Comparative Example 2 140.3 0.84 Comparative Example 2-1 102.1 1.33

As shown in Table 1, the microparticle size analysis of Example 1, Example 1-1, Example 1-2, and Comparative Example 1 showed an average particle size of about 35 μm, depending on the presence or absence of calcium chloride or the amount of calcium chloride. It was confirmed that there was no change.

As shown in Table 1, Example 2, Example 2-1 and Example 2-2 increased the average particle size according to the pore size of the membrane used for preparing the microspheres, it was confirmed that the average particle size can be adjusted based on this.

Based on Example 3, Example 3-1, and Example 3-2, the dispersion phase is prepared by adjusting the concentration of a polymer having the same pore size and the amount of solvent for dissolving polycaprolactone in a similar manner. It was confirmed that microspheres having a similar average particle size can be prepared while using polymers having different viscosities.

Experimental Example 3: Measurement of Bulk Density and Tapped Density

In this experiment, the physical properties of microspheres were determined by measuring the weight of microspheres occupying unit volume. The bulk density was measured by filling the microspheres up to the reference height in a 1 cm diameter, 5 cm high cylinder prepared for density measurement, measuring the weight of the filled microspheres, and dividing by the unit volume. As with the bulk density, the tap density fills the microspheres to the reference height of the cylinder, and then gently lowers the cylinder to the floor more than 50 times to fill the microspheres with as much empty space as possible. At this time, the tap density was measured by dividing the microspheres weight by the measured volume. The results are shown in Table 2.

Bulk Density (g / cc) Tap Density (g / cc) Example 1 0.36 0.44 Example 1-1 0.26 0.37 Example 1-2 0.19 0.29 Comparative Example 1 0.54 0.72 Comparative Example 1-1 - -

As shown in Table 2, the bulk density and tap density of Example 1, Example 1-1, and Example 1-2 were confirmed to decrease as the amount of calcium chloride increases. It is expected that as the calcium chloride increases, pores on the surface and inside of the microspheres are further developed to reduce the density of the particles.

In Comparative Example 1, the polycaprolactone microspheres prepared without using calcium chloride were found to have a relatively high tap density of 0.72.

In the case of Comparative Example 1-1, too much calcium chloride was used to dissolve the calcium chloride in the disperse phase. However, even when methyl alcohol was excessively used, calcium chloride could not be completely dissolved, making it difficult to manufacture.

Experimental Example 4: Injectability Test of Microspheres

This experiment was carried out to determine the injection capacity of the microspheres by measuring the microsphere recovery rate when the microspheres were administered using a specific needle. The experimental procedure is as follows.

The test microsphere suspension was prepared in the same manner as the polycaprolactone microsphere filler prepared in Examples 4 and 4-1, and the microspheres were prepared in Examples 2, 2-1, 2-2, and Comparative Examples. It carried out using 2 and the comparative example 2-1. The prepared polycaprolactone microsphere filler was divided into 1 g each in a 1.5 mL tube and collected with a syringe equipped with a 26 gauge needle, and the recovered microspheres were dried and weighed to calculate a recovery rate.

Recovery rate (%) Example 2 95.8 Example 2-1 95.4 Example 2-2 90.7 Comparative Example 2 18.7 Comparative Example 2-1 47.6

As shown in Table 3, Example 2, Example 2-1 and Example 2-2 showed a recovery value of 90% or more with a span value of 1.0 or less. It was predicted that the injection capacity was improved by reducing needle blockage when the average particle size of the microspheres was about 100 μm or less and had a uniform size.

On the contrary, in Comparative Example 2 and Comparative Example 2-1, when the average particle size is excessively large or the average particle size is about 100 μm, but the particle size has a non-uniform particle size distribution with a large span value, the microspheres block the needle and lead to a decrease in the injection capacity. It was confirmed.

Claims (16)

Characterized by having an average particle size of 10-100 μm, a tapped density of 0.5 g / cc or less, a span value of 1.0 or less, and an intrinsic viscosity of polycaprolactone of 0.16-1.90 dL / g , Polycaprolactone microspheres. delete The polycaprolactone according to claim 1, wherein the recovery rate of the microspheres is 80 g (w / w) or more in recovery with a syringe equipped with a 26 gauge needle after dividing 1 g in a 1.5 mL tube. Microspheres. (a) dissolving polycaprolactone in a first solvent and calcium chloride in a second solvent to prepare respective solutions, and then uniformly mixing the two solutions to prepare a single solution to prepare a dispersed phase;
(b) moving the dispersed phase through a membrane with holes of uniform size to an aqueous solution containing a surfactant (continuous phase) to produce an emulsion;
(c) extracting and evaporating the first solvent and the second solvent in a continuous phase from the dispersed phase in the emulsion prepared in step (b) to form microspheres; And
(d) recovering the microspheres from the continuous phase of step (c) to produce porous uniform polycaprolactone microspheres,
The calcium chloride is 0.01 to 15% by weight relative to the weight of the total dispersed phase solute,
The polycaprolactone has an intrinsic viscosity of 0.16 ~ 1.90 dL / g,
Characterized in that the average particle size of the microspheres is 10-100 μm, the tap density is 0.5 g / cc or less, and the span value is 1.0 or less,
Method for producing polycaprolactone microspheres. delete delete The preparation of polycaprolactone microspheres according to claim 4, wherein the first solvent of step (a) is at least one selected from the group consisting of dichloromethane, chloroform, ethyl acetate, methyl ethyl ketone, and a mixed solvent thereof. Way. The method of claim 4, wherein the second solvent of step (a) is at least one selected from the group consisting of methyl alcohol, ethyl alcohol and a mixed solvent thereof. The method of claim 4, wherein the surfactant of step (b) is methylcellulose, polyvinylpyrrolidone, carboxymethylcellulose, lecithin, gelatin, polyvinyl alcohol, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene castor oil derivative And mixtures thereof, wherein the method for producing polycaprolactone microspheres is one or more selected from the group consisting of. The method of claim 4, wherein the surfactant of step (b) is from 0.01 w / v% to 20 w / v% based on the total volume of the aqueous solution including the surfactant. 2 to 50% by weight of polycaprolactone microspheres having an average particle size of 10 to 100 µm, a tap density of 0.5 g / cc or less and a span value of 1.0 or less; Solute 0.1-5% by weight; 0-48% by weight of lubricant; And 15-97.9% by weight of a pharmaceutically acceptable aqueous carrier;
Polycaprolactone microsphere filler, characterized in that the intrinsic viscosity of the polycaprolactone of the microspheres is 0.16 ~ 1.90 dL / g. The method of claim 11, wherein the solute is carboxymethyl cellulose (CMC), hydroxypropyl methyl cellulose (HPMC), hyaluronic acid, lidocaine, polydeoxyribonucleotide (PDRN), polynucleotide (PN) and their Polycaprolactone microsphere fillers, characterized in that at least one selected from the group consisting of mixtures. 12. The polycaprolactone microsphere filler according to claim 11, wherein the lubricant is glycerin. 12. The polycaprolactone microsphere filler according to claim 11, wherein the pharmaceutically acceptable carrier is purified water, saline or phosphate buffer. The polycaprolactone microsphere filler of claim 11, wherein the filler is for wrinkle improvement, soft tissue repair or volume expansion, or contour correction. A prefilled syringe filled with the polycaprolactone microsphere filler according to any one of claims 11 to 15.

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