KR100840394B1 - Injectable polymer biodegradable granules for tissue regeneration and how to produce method there of - Google Patents

Abstract

A method for preparing a porous biodegradable support particle for injection is provided to improve the adhesion to skin tissue and endothelial cell and to allow the particle size and shape of support particles to be controlled. A method for preparing a porous biodegradable support particle for injection comprises the steps of mixing a biodegradable polymer dissolved in an organic solvent by a concentration of 1.5-20 wt% and water in a ratio of an organic solvent and water of 30-90 :10-70 by weight with stirring with a velocity of 2,000-5,000 rpm at 20-40 deg.C for 20-30 min to prepare an emulsion, injecting the emulsion into a mold, freezing it at -80 deg.C or less, freeze-drying it at -40 to -50 deg.C and foaming it; pulverizing the foamed one by repeating at least one set comprising the 10 repeated pulverization processes with a velocity of 300-1,000 rpm at an external temperature of 20-25 deg.C and an internal temperature of 15-20 deg.C for 5-10 sec, mixing the pulverized one with an emulsifier aqueous solution, freeze-drying it, and sterilizing it.

Description

Tissue regeneration biodegradable scaffold particles for injection injection using a biodegradable polymer and a method for preparing the same {INJECTABLE POLYMER BIODEGRADABLE GRANULES FOR TISSUE REGENERATION AND HOW TO PRODUCE METHOD THERE OF}

1 is a process diagram for preparing biodegradable support particles for injection.

2 is a simplified diagram of an example of a mill introduced into the milling process of the present invention.

Figure 3 is an electron micrograph of the biodegradable support particles for injection prepared in Example 1 of the present invention.

Figure 4 is a thermal analysis of the biodegradable support particles for injection prepared in Examples 1 to 4 of the present invention.

Figure 5 is a measurement of the weight average molecular weight (Mw) of the PGE of the biodegradable support particles for injection prepared in Examples 1 to 4 of the present invention.

6 is an analysis data of PLGA used in Examples 1 to 4 of the present invention.

7 is a graph showing experimental data in which the decomposition time increases as the content of lactide among the contents of PLGA used in Examples 1 to 4 increases.

[Simple explanation of symbols shown in drawings]

1. Organic solvent 2. Biodegradable polymer 3. Emulsifier

4. High speed stirrer 5. Liquid nitrogen tank 6. Vacuum freeze dryer

7. Grinder 8. Valve 9. Sterile Water

10. Mannitol Solution 11. Sodium Carboxymethylcellulose

12. Mixing Tank 13. Ethylene Oxide Sterilizer 14. Packing Machine

The present invention relates to biodegradable support particles for porous injection using a biodegradable polymer and a method for preparing the same.

Biodegradable polymer is a material that is easy to attach and grow to epithelial tissue, various tissues and skin cells in the human body, and is biodegradable and absorbed or released into human body after growth of such cells or tissues. It's massive.

First, looking at the development process of the material for medical polymers, the first generation can be referred to as the level of artificial implants, prostheses in the early days, ceramics, metals, composites and polymer materials were used as materials for prosthetics, supports and the like.

The second generation used general industrial materials to replace some of the damaged organs, with the materials used as inerts with no effect on living organisms. As a material for this purpose, polymethyl methacrylate bone cement, polyvinyl chloride plasticized with dioctyl phthalate, and the like have been used for blood bags.

The third generation used bioactive materials rather than inactive ones, and was used for artificial hips coated with apatite hydroxide, artificial blood vessels coated with collagen and alginic acid, and the like.

In the fourth generation, the development of mixed artificial organs, etc., using tissue cells and synthetic materials is being actively progressed, and various commercial situations are available.

On the other hand, the problem of recently produced artificial organs using a general purpose synthetic polymer as a material is due to the fundamental limitations of these materials, and lack of biocompatibility and biofunctionality to damaged organs or tissues of specific parts. In order to solve this problem, immobilization of non-degradable polymers or degradation of cells or proteins of organs and tissues is immobilized, and the cells are cultivated based on this, and hybridization is similarly made in order to further enhance and functionalize the performance of desired tissues or organs. I'm doing it.

Currently, the development and application of artificial organs and materials such as bones, salivary glands, urinary tract, epithelial tissue, bladder, skin, cartilage, damaged nerve cells, blood vessels, and skin care are actively progressing. An example is the microencapsulation of Langerhanson cells with agarose or algin-polylysine. This type is also applied to endocrine systems such as thyroid and parathyroid. Another representative of the hybrid artificial reactor is artificial liver, for example, which makes the atmosphere to grow and maintain liver cells in the form of a reactor to perform the typical detoxification, blood purification, etc. that can be performed by the liver cells Let's do it.

Representative examples of organ tissue engineering at present include artificial skin aprigraphs and derma grafts, which were approved by the US Food and Drug Administration (FDA) in May 1998, for use in treating diabetic skin ulcers. Designed. In addition, Cartisel, which was approved by the US Food and Drug Administration in August 1997, is an artificial cartilage for knee surgery developed by the venture-type company Genzyme Tissue Repair. It is seeded and surgically implanted back into the knee.

However, the material currently commercialized as described above has a problem that the material itself easily causes blood clots and embolism in the human body, and also has a problem of remaining and accumulated in vivo because it is non-biodegradable.

In order to solve the above problems, a basic technique using a biodegradable polymer that can be biodegraded after a certain period of time without accumulating in a living body is applied [D. J. Mooney, C. Breuer, K. Mcnamara, J. P. Vacanti, and R. Langer, Tissue Engineering, 1 (2), 107-118 (1995)].

First, in order to make a biodegradable polymer into a porous sheet, a 250 μm salt single crystal and a biodegradable polymer solution are mixed and formed into a desired thickness, and then salt is dissolved in water to form pores in the polymer sheet. The porous sheet thus prepared is dried and then rolled into a cylindrical shape having a desired diameter to bond both ends with an adhesive to produce a porous tube.

The sheet produced by the above manufacturing method has a problem that the pore structure is separated in the process of melting and drying the salt by dissolving salt with water because the size distribution of the salt single crystal is not uniform. After the grinding process, there is a problem in that the time to biodegrade due to water is shortened.

Currently, biodegradable polymers are widely used ester copolymers of lactide and glycolide, and their biodegradation principle is due to hydrolysis.

Polylactic acid (PLA) is currently used to manufacture prosthetic plates and screws to fix broken bones, while polyglycolic acid (PGA) is used as absorbent sutures. The polylactic acid and the polyglycolic acid have a biodegradation period of each homopolymer, but it is usually 1 year or more, whereas their copolymer PLGA [Poly (D, L-Lactide-Co-Glycolide)] has a change in average molecular weight. It takes several weeks to several tens of weeks to decompose in vivo.

Current requirements for tissue regeneration products using cellular tissue engineering include: no unwanted hyperimmune reactions during transplantation, affinity with surrounding tissues in the human body, and a bioadhesive surface without rejection. For this purpose, the control of the wettability (hydrophilicity / hydrophobicity ratio) on the material, the roughness on the surface, the porosity and the control of the type of surface charge is a technical problem to be solved.

In addition, tissue regeneration materials to which synthetic polymers and other polymers are currently applied are pointed out as a problem to be solved, such as the presence of flow phenomenon at the injected site.

Therefore, the inventors of the present invention have tried to develop a method for producing a biodegradable polymer, which is an essential element in the development of the scaffold for tissue engineering.

In other words, the particle shape of the main material using the biodegradable polymer is different from the conventional circular, elliptical, and the like, each particle is connected to each other rather than being separated individually upon injection into the target site. Research efforts have been made to develop a manufacturing method that enables the system to be made.

The present invention has a characteristic that biodegradation occurs for several months after being injected into the human body, so that the biodegradable polymer harmless to the human body is used, and after the injection into the mold by changing the rotational speed of the stirrer in order to produce the particles in the required form. After freezing and lyophilizing and foaming again, using a specially designed grinder, grinding is performed by adjusting the grinding speed and interval under the condition that the temperature of the cooling coil is controlled so that the temperature inside and outside the grinder is kept constant. Water itself is used, or it is mixed with an emulsifier aqueous solution and lyophilized, followed by sterilization.

The biodegradable support particles for injection prepared by the method of the present invention have various sizes and irregular shapes so that they are injected without the bottleneck when injected into a syringe, and are effective for adhesion of various cells and growth of tissues of the human body. Applicable

Accordingly, it is an object of the present invention to provide an amorphous biodegradable support particle for various types and shapes of porous injection injection.

It is another object of the present invention to provide a method for preparing the above-described amorphous biodegradable support particles for porous injection.

One or more biodegradable polymers selected from the group consisting of polylactic acid, polyglycolic acid, copolymers of lactic acid and glycolic acid, albumin, collagen, polyhydroxy butyric acid, polycaprolactone and polyanhydrides It consists of, the weight average molecular weight (Mw) of the biodegradable support particles in the range of 90,000 ~ 110,000, the particle size of 10 ~ 200 ㎛ has an amorphous structure and the wettability imparted biodegradable support particles for injection injection do.

In addition, the present invention is prepared by mixing the biodegradable polymer dissolved in the organic solvent with water and stirring at 20 to 30 minutes at a stirring speed of 2,000 to 5,000 rpm under the condition of maintaining the temperature in the high speed stirrer in the range of 20 to 40 ℃. One emulsion solution was added to a mold, and frozen at a temperature of -80 ° C or lower, followed by lyophilization and foaming at -40 to -50 ° C. And maintaining the internal temperature in the range of 15 to 20 ° C., comprising the steps of repeating at least one part with a pulverization rate of 300 to 1,000 rpm and a condition of repeating the grinding 10 times for 5 to 10 seconds to 1 part. It includes a method for producing a biodegradable support particles for porous injection injection.

In addition, the present invention is prepared by mixing the biodegradable polymer dissolved in the organic solvent with water and stirring at 20 to 30 minutes at a stirring speed of 2,000 to 5,000 rpm under the condition of maintaining the temperature in the high speed stirrer in the range of 20 to 40 ℃. One emulsion solution was added to a mold, and frozen at a temperature of -80 ° C or lower, followed by lyophilization and foaming at -40 to -50 ° C. In the conditions of maintaining the internal temperature range of 15 ~ 20 ℃, the pulverized product obtained by repeatedly performing at least 1 part with the conditions of the pulverization rate 300 ~ 1,000 rpm, 10 times repeated grinding for 5 to 10 seconds to 1 part, Characterized by a method for producing a biodegradable support particles for porous injection, comprising the step of lyophilizing and mixing with an aqueous solution of an emulsifier.

Hereinafter, the present invention will be described in detail.

According to the present invention, biodegradable polymers can be applied to various tissue cells such as endothelial cells or skin tissue cells in the human body to be applied by giving an appropriate change in the manufacturing process according to the intended use, and can advantageously act on tissue growth when used. After the growth of the skin tissue is complete, it is naturally biodegradable and absorbed or released into the human body, and thus, an improved amorphous biodegradable support particle for porous injection injection, which is expected to be used as a support for tissue regeneration according to its application and industrial use. It relates to a manufacturing method thereof.

When culturing tissue cells using biodegradable scaffold particles, the cells grow smoothly when they adhere well to the surface of the used polymer. Thus, the growth of cells also depends on the surface properties of the polymer constituting the biodegradable support particles and the pores between the biodegradable support particles comprising the polymer. To this end, wettability (hydrophilicity / hydrophobicity ratio), surface chemical properties, types of surface charges and surface roughness should be given. At this time, it is better to give hydrophilic property than to give hydrophobicity to the surface in that the raw material is injected into the syringe and the particles are evenly injected when injected into the human body, and the charge on the surface is configured to be positively charged rather than negatively charged. It is advantageous for the cells to adhere to the support, and also for the growth of adhered cells.

In the present invention, in order to give roughness to the surface of the polymer constituting the biodegradable support particles in order to favor the growth of cells, the grinding conditions are repeatedly pulverized without changing the temperature and the grinding speed. There is a characteristic of technical construction in changing the number of changes. In other words, the roughness of the biodegradable support particles may be changed by the pulverization conditions presented to various cells on the surface of the biodegradable support particles, for example, epithelial cells, ovary cells, chondrocytes, and adult vascular endothelial stems. The cells may be cultured and used, and the cultured cells and particles may be used for each applied tissue.

The present invention produces a biodegradable support particles having a rough surface by pulverizing the foamed sheet after the foaming process with a biodegradable polymer, an organic solvent and water, and the state of the biodegradable support particles to create an environment in which cells can grow well. Since it can be produced in a desired direction, it is possible to grow and recover tissue cells, and after a certain period of time, there is no fear of being naturally decomposed and absorbed in vivo and accumulated in the human body.

Hereinafter, the present invention will be described in detail step by step based on the manufacturing method.

First, freeze-drying and foaming of an emulsion solution prepared by mixing a biodegradable polymer dissolved in an organic solvent with water.

Biodegradable polymers used in the present invention is generally used for the regeneration of biological tissues and repair of skin tissues, and can be used polymers preceded by biodegradability and biocompatibility. And by selecting a biodegradable polymer that meets the decomposition period shown in the data of Table 2, Figure 7, and the like through the emulsification and foaming process using a special mill to adjust the size of the desired particles, which can be used in the present invention The polymer should be harmless to human body and have the property to be biodegradable within the desired period.

Biodegradable polymers satisfying these conditions include one or two selected from polylactic acid, polyglycolic acid, copolymers of lactic acid and glycolic acid, albumin, collagen, polyhydroxy butyl acid, polycaprolactone and polyanhydride. Mixtures of species or more may be used. Preferably, a copolymer of lactic acid and glycolic acid may be used. The copolymer of lactic acid and glycolic acid may include a lactic acid monomer selected from L-lactic acid, D-lactic acid, and D, L-lactic acid, and a glycolic acid monomer from 50 to 75. The copolymer included in the range of 25 to 50 molar ratio may be used, and specifically, a copolymer composed of 75:25 molar ratio of D, L-lactic acid and glycolic acid, and a 65:35 molar ratio of D, L-lactic acid and glycolic acid It is preferable to use a copolymer and a copolymer in which D, L-lactic acid and glycolic acid are composed of 50:50 molar ratio.

The biodegradable polymer has been found to be naturally biodegraded after a certain period of time in the human body by hydrolysis and various enzymes in the human body [langer. R Vacanti J. P., Science 260, 920, 1993].

The biodegradable polymer may be used in the range of the weight average molecular weight (Mw) 10,000 ~ 150,000, preferably with reference to the data of Figure 7 lactide / glycolide molar ratio is consistent with the workability and decomposition period of the current process This was 75/25 and the average molecular weight ranged from 100,000 to 150,000.

The biodegradable polymer is dissolved in an organic solvent and mixed with water. At this time, the organic solvent and water used are preferably mixed in a weight ratio of 30 to 90:10 to 70. The organic solvent may be used one or a mixture of two or more selected from acetonitrile, dichloromethane, chloroform, tetrahydrofuran, dioxane and methylene chloride.

The biodegradable polymer is included in the concentration of 1.5 to 20% by weight, preferably 2 to 18% by weight in the emulsion solution, wherein if the concentration of the biodegradable polymer is greater than 20% by weight or less than 1.5% by weight, the biodegradable polymer is crushed after foaming It is preferable to maintain the range as much as possible because the shape of the particles may be incorrect and the density of the tissue may increase when the tissue is grown, thereby preventing the growth of the tissue.

In addition, additives such as antioxidants, emulsifiers, thickeners, hydrophilicity-imparting agents and the like can be appropriately used within the scope of not impairing the object of the present invention, and it is apparent that the present invention is not limited by the selection of such additives.

The emulsion solution containing the biodegradable polymer is made into a complete emulsion solution using a high speed stirrer and then foamed. Stirring depends on the type of biodegradable polymer, the cell or tissue to which the biodegradable support is to be applied, etc., but is performed at 2,000 to 5,000 rpm, preferably 4,000 to 5,000 rpm, for 20 to 40 minutes, preferably for 20 to 30 minutes. It is good. Specifically, in the case of using 1 kg of an emulsion solution, a uniform emulsion solution may be obtained when the emulsion solution is performed at 5000 rpm for 20 to 30 minutes. The temperature condition at the time of stirring is room temperature (20 degreeC)-40 degreeC, and it is good in terms of the physical deformation of the biodegradable polymer material itself, and the homogenization of particle | grains to comprise so that the stirrer's own temperature cannot exceed 40 degreeC.

Foaming is carried out by lyophilizing the emulsion solution, before freezing-drying the emulsion solution, freezing in the range of -80 ° C or lower, preferably -196 ° C to -85 ° C, and freeze-drying in the range of -40 ° C to -50 ° C. It is good to carry out. It is preferable to apply the grinding process to the foam produced in the form of a sheet, but it is not necessary to prepare the sheet in the form of a sheet.

The mold used for freezing the emulsion solution is not particularly limited in kind, but it is generally preferable to use a Teflon mold or a metal alloy mold in terms of not impairing the physical properties of the emulsion solution, and to limit only the sheet phase. Since the emulsified biodegradable polymer should be easily detached from the mold, the material of the mold is not necessarily determined. The freezing method performed before the lyophilization may generally be performed under liquid nitrogen conditions, or may be performed using a deep freezer or the like. It is preferable to freeze for at least 1 hour in liquid nitrogen, and to freeze at least 6 hours in a deep freezer.

Next, the foam is pulverized at a controlled pulverization rate and time under conditions adjusted to maintain a certain range of temperature inside and outside the pulverizer, and then mixed with an aqueous solution containing an emulsifier, followed by lyophilization. At this time, as the emulsifier, it is more preferable to mix and use mannitol and sodium carboxymethyl cellulose.

The pulverizer in which the pulverization process of the present invention is performed is configured such that a cooling coil or the like is mounted on the outside to maintain a temperature inside and outside the pulverizer in a predetermined range.

That is, the external temperature of the grinder is maintained in the range of 20 to 25 ℃, the internal temperature is maintained at a lower range of 15 to 20 ℃ range, the grinding speed is 300 to 1000 rpm, preferably 500 to 1000 rpm Repeat the grinding process for 5 to 10 seconds. To this end, the temperature of the cooler, such as the cooling coil mounted on the outside of the mill, may be maintained at about 15 ° C.

The particles of the pulverized product obtained by the pulverization are adjusted to have a size of 10 to 200 μm in accordance with the desired particle size. In this case, the pulverized product is an amorphous particle size, and the biodegradable support particles prepared by lyophilization refer to particles after the pulverized products are connected.

Specifically, when the foam is defined as 1 part on the basis of the pulverization rate in the range of 300 to 1000 rpm, and repeat the grinding 10 times for 5 to 10 seconds, 1 part or more, preferably 1 to 5 Crushed.

That is, when the grinding is less than 1 part in the grinding, the average size of the particles in the range 20 ~ 200 ㎛, less than 2 parts the average size of the particles is 20 ~ 150 ㎛, less than 3 parts the average size of the particles is in the range 20 ~ 100 ㎛ do. Through such a grinding process, the particles having a size of less than 10 μm are adjusted to be less than 60 wt%. At this time, when the particle size is more than 4 parts, particles having a size of 10 μm or less occupy 60% or more, which is not preferable. The reason is that the average size of the cell is about 10㎛ may not be good for cell adhesion and may cause problems in the formation of pores of the support during injection.

The pulverization is performed at 47 ° C. to 51 ° C. when the molar ratio of lactide / glycolide is 85/15 with reference to the data of FIG. 4 of the biodegradable polymer constituting the foam. In the case of ℃ ~ 52 ℃, 65/35 is carried out by adjusting the grinding temperature and grinding time to the desired particle size in consideration of the glass transition temperature of 45 ℃ ~ 50 ℃.

In addition, in general, the grinding speed of the mill is 300 ~ 1,000 rpm and preferably 500 ~ 1,000 rpm is suitable. If the particle size is less than 300 rpm, the pulverized particles appear to be larger than 200 μm, and more than 1,000 rpm may cause the particles to deform due to a sharp increase in temperature in the pulverizer.

The grinding may be controlled during the manufacturing process by adjusting the grinding conditions in consideration of the glass transition temperature of the biodegradable polymer, the particle size and the particle size and the size of the particles as shown in the data shown in FIG. In addition, since the size of the tissue cells is approximately 10㎛ range to match the purpose of each tissue regeneration to predict the decomposition time of the biomaterials as shown in the data attached to Figure 7 to control the size of the particles and tissue to the desired tissue site Regeneration time, decomposition time of the biomaterial, particle size can be adjusted to obtain the characteristics of the effect of the tissue repair and fixing to the living body.

That is, by controlling the temperature conditions at the time of pulverization based on the glass transition temperature of the biodegradable polymer, respectively, and by controlling the pulverization speed and time and the number of repetitions of the pulverizer as described above, it does not cause deformation of the biodegradable polymer. 1 shows an example of a mill that can be applied to the mill, a mill having a three-dimensional blade and an external cooling coil device as an element.

Since the density of the particles is reduced to a level of 20 to 60% through foaming during the preparation of the biodegradable support particles, the biodegradable support particles may be applied as injection-injectable biodegradable support particles.

The crushed foam is mixed with an emulsifier aqueous solution and lyophilized. These emulsifiers include mannitol or water soluble calcium, sodium carboxymethyl cellulose, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, agar, hemicellulose, pentosan, galactan, pectin, gum, lignin, starch, One or a mixture of two or more selected from the group consisting of amylose, amylopectin, water-soluble chitosan, and the like may be used. Preferably, an aqueous solution of mannitol (50/250% (w / v)) and sodium Freeze-dried by mixing with a mixed aqueous solution of carboxymethyl cellulose. The pulverized product obtained by pulverizing the foamed product includes emulsions such as mannitol and sodium carboxymethyl cellulose as solids in an emulsifier aqueous solution, and an amount of pulverized product (biodegradable polymer such as PLGA) in the range of 5 to 50% by weight. The following is included in the range of 5 to 20% by weight. If the content of solids, including emulsifiers such as mannitol, sodium carboxymethylcellulose, and biodegradable polymers, exceeds the above range, it is difficult for the solids to pass through the syringe and may be pressured in the syringe, causing damage to the cells. If it is below the range, solids are reduced to form a support when passing through a syringe. Therefore, it is better to adjust to the above range.

When mannitol and sodium carboxymethyl cellulose are used as the emulsifier, mannitol in the total weight of solids excluding water in the mixed aqueous solution is preferably 0.05 to 0.1 wt%, preferably 0.08 wt%, and sodium carboxymethyl cellulose is 0.1 to 2 By weight, preferably 1.7 to 2% by weight, the pulverized (biodegradable polymer) particles preferably contain 97.92 to 98.22% by weight. The mannitol (50/250% (w / v)) may be included in the range of 0.1 to 5% by weight when included in the aqueous phase.

The pulverized mixture is mixed with the aqueous solution of the emulsifier, and lyophilized to prepare a porous biodegradable support particle for injection, after undergoing sterilization with ethylene oxide.

The mannitol prevents each component from adhering to the container when performing lyophilization, and sodium carboxymethyl cellulose increases the viscosity of the solution when injecting the biodegradable support particles into the human body so that the particles smoothly pass through the syringe. do.

The viscosity of the solution containing the biodegradable support particles to adjust the amount of the emulsifier such as sodium carboxymethyl cellulose to be adjusted to about 25 ℃ 1,000 ~ 5,000 cps is preferably 25 ℃ 1,000 ~ 2,000 cps. Overdose may interfere with the human incorporation of biodegradable support particles.

The porous biodegradable support for injection injection of the present invention prepared as described above has a weight average molecular weight (Mw) in the range of 90,000 to 110,000, the average size of the particles is 10 ~ 200 ㎛, having an amorphous structure, for injection injection Adjust the grinding time and number of times to show the particle size to be used sufficiently, and to accurately count the number of times, time, and temperature of the above-mentioned grinder in order to prevent the size of the particles from being shaped, Applicable

In addition, when the sodium carboxymethyl cellulose is added, the wettability is forcibly imparted, so that the bottleneck in which the biodegradable support particles are not injected through the injection can be better resolved. The degree of attachment is better.

As is generally known, for efficient cultivation of cells, the substrate must have the ability to adsorb on the cells, promote the growth of the cells, maintain the function of the cells, biocompatibility, biodegradability, particle size and use. As it is necessary to have a property, it will be highly applicable in relation to artificial tissue and skin beauty by cell culture. In addition, the biodegradable support particles of the present invention prepared by the above production method can be applied to all tissues that require recovery of various cellular tissues, including skin regeneration.

Hereinafter, the present invention will be described in detail with reference to the following Examples, the present invention is not limited by the Examples.

Examples 1-4

0.8 g of PLGA [weight average molecular weight (Mw) 97,400] copolymerized with lactic acid and glycolic acid at 75:25 was dissolved in 8 ml of methylene dichloride, which was water and weight of 60:40. After mixing at a ratio, the mixture was stirred at a high speed stirrer for 5,000 rpm for 20 to 30 minutes to prepare an emulsified solution, and then instantaneously added to a Teflon mold and immediately frozen in a liquid nitrogen tank and a deep plunger below -80 ° C. Let's do it. After freezing in the liquid nitrogen tank for 2 hours and freezing in the deep plunger for 5 hours, a foamed sheet was prepared by lyophilization using a vacuum freeze dryer of -50 ° C.

The sheet is pulverized using a grinder having a structure as shown in FIG. 2 at 25 ° C. at an internal 20 ° C. temperature, and the cooling coil temperature is maintained at 15 ° C., and the grinding speed of the grinder is 1,000 rpm at 10 second intervals. 4 parts of repeated grinding was carried out with the conditions of 1 time grinding | pulverization, and the particle | grains of the average size of 10-60micrometer were obtained.

97.92 to 98.22% by weight of the pulverized powder particles (based on solids), 0.4% by weight of aqueous mannitol solution (50/250% (w / v), 0.08% by weight) and sodium carboxymethylcellulose (2% by weight) 1.9% by weight, 1.8% by weight, 1.7% by weight, and solids (based on solids or more), followed by stirring with an amount of purified water that achieves the viscosity shown in Table 1 below, and then vacuum lyophilization at -50 ° C, followed by ethylene Oxide was sterilized.

Examples 5-8

Biodegradable support particles were prepared using poly L-lactide (PLLA) in the same manner as in Example 1.

Comparative Example 1

0.8 g of PLGA (weight average molecular weight (Mw) 97,400) copolymerized with lactic acid and glycolic acid (glycolic acid) at 75:25 was dissolved in 8 ml of methylene dichloride, which was water and a weight of 10:90. It mixed at the ratio and the other process was configured similarly to Example 1. As a result, no particles of biodegradable polymer were produced.

Comparative Example 2

0.8 g of poly L-lactide (PLLA) was dissolved in 8 ml of methylene dichloride, mixed with water at a weight ratio of 10:90, and the other processes were configured in the same manner as in Example 1. As a result, no particles of biodegradable polymer were produced.

Comparative Example 3

The same process as in Example 1 was applied as a whole, but instead of emulsifying, foaming with salt, desalting and drying with water, and then pulverizing machine produced particles using a general pulverizer. The size of the particles is more than 150㎛ on average, it is difficult to pass through the syringe and the decomposition time is also accelerated by water decomposition was decomposed about 2 ~ 4 weeks faster than the data of Figure 7.

Experimental Example: Measurement of Physical Properties

The following physical properties of the biodegradable support prepared in Examples 1 to 8 were measured, and the results are shown in Table 1 below.

1) Wetting: It shows the contact angle of water, and the contact angle on the PLGA film is 75 ~ 80 높은, so it has high interfacial free energy in aqueous solution, which adversely affects cell adhesion and growth.

2) Surface charge: Surface charge is also similar to the contact angle of water, so all the nanoparticles in the molecular structure are stable with negative charge. The measurement was carried out using a zeta potential difference device.

3) Viability of cells in aqueous solution: The survival of dermal cells in aqueous solution (mannitol, sodium carboxymethyl cellulose, distilled water) was confirmed.

4) Tensile strength: measured based on ASTM D 638: 2003 method.

5) Elongation: measured based on ASTM D 638: 2003 method.

6) Modulus: Measured based on KSM ISO 01827 method.

7) Shore D-Hardness: Measured based on KSM ISO 2039-2: 2003 method.

8) Glass transition temperature: measured by DSC, and the principle is indicated by extrapolation contact connecting the tangent between the baseline before the reaction occurs and the inflection point of the endothermic reaction that occurs after the reaction, and the extrapolation contact between the inflection point and the baseline after the reaction. do. Since the exact glass transition temperature cannot be interpreted, some errors may occur depending on the interpreter.

9) Solvent Stability: 100 ml of each organic solvent was taken and measured by stirring for 24 hours to determine whether the particles were dissolved in the organic solvent as a whole.

According to the above results, according to the embodiment of the present invention, a biodegradable support having an average particle size in the range of 50 to 150 μm is obtained, and the size of the international standard needle is 20G. But it's not limited to 20G. In addition, the shape of the particles appears to be indeformed, which can be confirmed by the electron micrograph [Example 1] shown in FIG.

On the other hand, if there is an excessive amount of water in the emulsion solution as in Comparative Examples 1 and 2 may cause a big problem in particle generation.

The prepared biodegradable support particles are mixed with the desired tissue site by adding physiological saline or autologous serum and respective tissue cells when used in an actual medical field, and the biodegradable support particles have an amorphous structure so that the syringes are used separately. The bottleneck does not appear and is easily injected into the human body to facilitate formation of a scaffold in the tissue. In addition, since the biodegradable support particles have an amorphous structure, attachment of cells and tissues occurs easily, and growth of cells and tissues preferably occurs.

As described above, the porous biodegradable support particles for injection injection made of the biodegradable polymer of the present invention are composed of various particle sizes and shapes, and effectively transfer substances such as nutrient solution, oxygen, carbon dioxide, etc. between the blood and the skin. Since the raw material itself is made of biodegradable polymer which is harmless to human body, it is easy to attach to endothelial cells and skin tissues in the human body and has the advantage of growth of cells.

Claims (11)

delete delete delete Mixed with a biodegradable polymer and water dissolved in an organic solvent at a concentration of 1.5 to 20% by weight, wherein the organic solvent and water are mixed in a weight ratio of 30 to 90:10 to 70, and the temperature in the high speed stirrer is maintained at a range of 20 to 40 ° C. Under the condition of stirring, the stirring solution was set at 2,000 to 5,000 rpm, and the emulsion solution prepared by stirring for 20 to 30 minutes was added to the mold, and frozen at a temperature condition of -80 ° C or lower, and then at -40 to -50 ° C. Lyophilization and foaming, The foamed material was repeatedly pulverized for 10 times in a pulverization speed of 300 to 1,000 rpm and 5 to 10 seconds under conditions in which the outside temperature of the crusher was maintained at a range of 20 to 25 ° C. and the internal temperature was maintained at a range of 15 to 20 ° C. Pulverizing the pulverized product obtained by repeatedly performing at least one part with lyophilized solution, lyophilized and then sterilized Method for producing a biodegradable support particles for porous injection, characterized in that comprises a. The method according to claim 4, wherein the biodegradable polymer is one or two selected from polylactic acid, polyglycolic acid, copolymers of lactic acid and glycolic acid, albumin, collagen, polyhydroxy butyl acid, polycaprolactone and polyanhydride. Method for producing a biodegradable support particles for porous injection, characterized in that the mixture of more than one species. The method of claim 4, wherein the biodegradable polymer has a weight average molecular weight (Mw) in a range of 10,000 to 150,000. delete delete delete The method of claim 4, wherein the pulverized product in the aqueous solution of the emulsifier is in the range of 97.92 ~ 98.22% by weight based on solids. The method of claim 4, wherein the emulsifier is mannitol or water-soluble calcium, sodium carboxymethyl cellulose, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, agar, hemicellulose, pentosan, galactan, pectin, gum, lignin The starch, amylose (amylose), amylopectin (amylopectin), and a method for producing biodegradable support particles for injection injection, characterized in that one or two or more selected from the group consisting of water-soluble chitosan.

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