KR100622996B1 - Nonporous microspheres including drug and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a non-porous polymeric microparticle carrier in which a drug is enclosed, a method for preparing the same, and a method of using the non-porous polymeric microcarrier in which a drug is encapsulated as a drug releasing agent to continuously release the drug in vivo.

Method for producing a non-porous polymer particulate carrier in which the drug of the present invention is encapsulated

(1) dissolving a hydrophilic polymer to form pores with a biodegradable polyester polymer in an organic solvent,

(2) dispersing and emulsifying the solution containing the polyester-based polymer and the hydrophilic polymer in an aqueous solution containing a hydrophilic surfactant,

(3) removing the organic solvent from the solution containing the polyester-based polymer after emulsification to obtain a porous polymer particulate carrier having a plurality of pores,

(4) obtaining a non-porous polymeric microparticle carrier in which the drug is encapsulated by enclosing the drug in the pores of the porous polymeric microparticle carrier and then contacting the organic solvent in a vapor state to close the pores of the porous polymeric microparticle carrier.

Description

Non-porous polymeric particulate carrier encapsulated with a drug and a method for preparing the same {Nonporous microspheres including drug and manufacturing method

Figure 1 is a schematic diagram showing a method for producing a particulate carrier for continuously controlled release of the drug of the present invention using a porous particulate carrier.

Figure 2 is a schematic diagram of a fluidized bed reactor (FBR), which is an implementation device of the technique for closing the pores of the porous particulate carrier.

3A is a surface and cross-sectional micrograph of a porous biodegradable particulate carrier containing a drug prepared according to an embodiment of the present invention.

3B is a surface and cross-sectional scanning micrograph of a biodegradable particulate carrier containing a drug that closes the pores of the particulate carrier (FIG. 3A) according to an embodiment of the invention.

Figure 4 is a graph showing the sustained release behavior of the carrier containing the drug prepared according to an embodiment of the present invention.

The present invention relates to a non-porous polymeric microparticle carrier in which a drug is enclosed, a method for preparing the same, and a method of using the non-porous polymeric microcarrier in which a drug is encapsulated as a drug releasing agent to continuously release the drug in vivo. More specifically, the non-porous particulate carrier in which the drug is enclosed in the pores of the porous particulate carrier having a plurality of pores and then the pores of the particulate carrier are encapsulated, a method for preparing the same, and a non-porous polymeric particulate carrier in which the drug is encapsulated The present invention relates to a method of using the drug release agent to allow the drug to be released continuously.

Injectable formulations and oral formulations which are generally used today have difficulty maintaining long-term drug concentrations in the body in a single dose.

Therefore, in order to maintain drug concentration for a long time in the body, the drug is encapsulated in a biodegradable polymer carrier, and as the polymer carrier is slowly degraded in vivo, studies are conducted on the preparation of the drug to be continuously released in the body. [K. Fu, R. Harrell, K. Zinski, C. Um, A. Jaklenec, J. Frazier, N. Lotan, P. Burke AM Klibanov R. Langer, J. Pharm. Sci. 92 (2003) 1582-1591; R. Langer, Acc. Chem. Res. 33 (2000) 94-101; WR Gombotz and DK Pettit, Bioconj. Chem. 6 (1995) 332-351, R. Langer and NA Peppas, Biomaterials , 2 (1981) 210-214].

In the case of introducing such a biodegradable polymer carrier system, the polymer carrier is slowly degraded in the body after injection to change into a low molecular material that is harmless to the human body. Therefore, there is an advantage that does not require a separate surgical removal of the polymer carrier after the drug is released for a certain period of time, the research has been continued to apply it to medicines.

Drug release control technology using such a biodegradable polymer carrier has been studied mainly in the application to small molecular weight bioactive materials. However, recently, high molecular weight peptides and proteins have been developed as new therapeutic drugs, and there have been various attempts to continuously release these drugs even in a polymer carrier.

Various polymer carriers are currently being developed and used. For example, aliphatic polyester has already been recognized for its biocompatibility and has been approved by the US Food and Drug Administration (FDA), and is widely used as a material for drug delivery carriers and surgical sutures.

Specific examples of such aliphatic polyesters include poly-L-lactic acid, polyglycolic acid, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co Glycolic acid (poly (D, L-lactic-co-glycolic acid), PLGA), poly-caprolactone, poly-valerolactone, poly-hydroxy butyrate and poly-hydroxy valerate, etc. [LB] Peppas, Inter. J. of Pharm. 116 (1995) 1-9].

The most widely studied and used method for encapsulating a water-soluble drug in such a particulate carrier composed of aliphatic polyester is W / O / W (Water-in-Oil-in-Water) method, which is a double emulsion method. to be.

This method has the advantage of being able to encapsulate most water soluble drugs into particulate carriers. However, harsh conditions exist during the encapsulation process, which affects the stability of the drug.

In particular, in the case of large drugs such as peptides and proteins, instability problems of drugs such as covalent / non-covalent aggregation, nonspecific adsorption, and denaturation occur in the process of encapsulation into the particulate carrier.

The main cause of this instability problem is the presence of an aqueous / organic solvent interface that occurs during the W / O / W process, and the presence of this interface is the largest cause of denaturation and aggregation of drugs such as proteins and loss of pharmacological activity. The cause has been found [HK Kim, TG Park, Biotech. Bioeng. 65 (1999) 659-667; H. Sah, J. Pharm. Sci. 88 (1999) 1320-1325; C. Perez-Rodriguez, N. Montano, K. Gonzalez, K. Griebenow, J. Control. Rel. 89 (2003) 71-85.

As a result of the drug stability problems, the initial burst effect of the drug and the problem of the drug not being released in the particulate carrier cause a great difficulty in controlling the drug to be released at a constant rate for a certain period of time. have. For example, in the case of protein drugs such as bovine serum albumin and lysozyme, the final release amount is about 50% after a large amount of drug is initially released [G. Crotts, and TG Park, J. Control. Rel. 44 (1997) 123-134; NB Leonard, LH Michael, MM Lee, J. Pharm. Sci. 84 707-712. In addition, when the recombinant human growth hormone (Recombinant Human Growth Hormone) is introduced into the particulate carrier of the aliphatic polyester, 30-50% of protein drug is initially excessively released, and then the amount of 40-60% cannot be released. It has been reported that it remains in the carrier [C. Yan, et al. J. Control. Rel. 32 (1994) 231-241.

In the process of encapsulating such a drug into a particulate carrier, many attempts have been made in various aspects to solve the problem of drug stability. In particular, a study to solve the problem of protein denaturation at the aqueous solution / organic solvent interface during the process of encapsulating protein drug in the polymer microparticle carrier.

One approach to this research was to investigate the approach to enhance protein stability at the aqueous / organic solvent interface by adding stabilizers [OL Johnson et al. Pharm Res. 14 (1997) 730-735; MA Tracy, Biotech. Prog. 14 (1998) 108-115. For example, Tween 20, Tween 40, Tween 80, Polyethylene glycol (PEG), Carboxymethyl cellulose, Mannitol, Trehalose, Dex Detran 70 and Gelatin have been found to reduce the denaturation of human growth hormone on aqueous / organic solvent interface, and by using mannitol, gelatin, trehalose, mannitol / trehalose, carboxymethylcellulose, etc. There is an example in which human growth hormone is applied to the preparation of a polymer particulate carrier encapsulated [JL Cleland and AJS Jones, Pharm. Res. 13 (1996) 1464-1475.

Another approach has been to formulate a method of changing the preparation itself so that the aqueous solution / organic solvent interface does not occur in the process of encapsulating the protein drug into the particulate carrier. For example, a method in which the protein itself is made into fine particles, directly dispersed in a dissolved organic solvent, and then encapsulated in a polymer microcarrier [T. Morita, Y. Sakamura, Y. Horikiri, T. Suzuki, H. Yoshino, J. Control. Rel. 69 (2000) 435-444], a method for preparing a particulate carrier by dispersing human growth hormone in a solvent together with a polymer, spraying at low temperature, and extracting the solvent [JL Cleland, OL Johnson, S. Putney, AJS Jones, Adv. Drug Deliv. Rev. 28 (1997) 71-84; OL Johnson et al. Pharm. Res. 14 (1997) 730-735. These are approaches that try to solve the problem by eliminating the generation of aqueous solutions / organic solvents that are the source of the problem.

However, even when the polymer microcarrier containing the protein was actually prepared using these approaches, there was still a problem that many drugs remained in the microcarrier even after the initial over-release and termination of release. For example, when a human growth hormone-containing polymer particulate carrier was prepared using gelatin, mannitol / carboxymethylcellulose, and carboxymethylcellulose as a stabilizer, the proportion of monomers in the encapsulated human growth hormone was about 66 to 76%. It was only.

As such, many of the techniques for producing particulate carriers that are applied to general drugs, particularly protein drugs, to continuously release the drug in vivo remain unresolved.

The inventors of the present invention have conducted many years of research and efforts to develop a microcarrier that suppresses initial over-release and continuously releases the drug in the body while maintaining the stability of a drug encapsulated in a polymer microcarrier, and thus clearly distinguished from the conventional particulate carrier manufacturing method. New drug-containing polymer particulate carriers have been established.

The particulate carrier which continuously releases the drug in the body of the present invention uses a biodegradable polymer to prepare a porous particulate carrier having a large number of pores, and injects the drug into the pores of the particulate carrier to obtain a water-soluble drug solution. The microcarrier formulation was developed by controlling the release rate of the drug by closing the pores of the particulate carrier by using a solvent, and the present invention was completed by confirming that the formulation continuously controlled release the drug at a constant concentration.

It is an object of the present invention to provide a nonporous polymeric particulate carrier in which a drug is enclosed.

Another object of the present invention is to provide a method for preparing a non-porous polymer particulate carrier in which a drug is enclosed.

It is still another object of the present invention to provide a method of using a drug release agent in which a drug-encapsulated nonporous polymer particulate carrier is continuously released in vivo.

The present invention for achieving the above-mentioned object includes a non-porous polymeric microparticle carrier in which the drug is sealed in the pores of the microcarrier made of a biodegradable polyester-based polymer and then the drug is closed.

The biodegradable polyester-based polymer, which is one of the main components of the non-porous polymer particulate carrier in which the drug of the present invention is encapsulated, may be used as long as it is harmless in the human body and can be slowly degraded and discharged into the body.

As an example of such a biodegradable polyester polymer in the present invention, poly-L-lactic acid, poly-glycolic acid, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid- Any one selected from co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, poly-caprolactone, poly-valerolactone, poly-hydroxy butyrate, poly-hydroxy valerate may be used.

Drugs encapsulated in the pores of the biodegradable polyester-based polymer in the present invention are human growth hormone (Human Growth Hormone), G-CSF (Granulocyte-Colony-Stiumulating Factor), GM-CSF (Granulocyte-Macrophage Colony-Stimulating Factor), Erythropoietin, BCG vaccine, hepatitis B vaccine, flu vaccine, Japanese encephalitis vaccine, influenza virus vaccine, measles virus vaccine, pneumococcal vaccine, typhoid vaccine, chickenpox virus vaccine, mumps virus vaccine, anti-hCG antibody, anti α-hCG antibody, anti-β-hCG antibody, IgG antibody, anti-LH monoclonal antibody, H.pylori antibody binding protein, purified OKT3 monoclonal antibody, insulin (Insulin), calcitonin, adrenocorticotropic hormone ), Glucagon, Somatostation, Somatotropin, Somatomedin, Parathyroid hormone, Thyroid stimulating hormone, Thyroid hormone, Progesterone stimulating hormone, Follicle stimulating hormone, Luteinizing hormone, prolactin, endorphin, vascular endothelial growth factor, enkephalin, oxytocin, vasopressin, nerve growth factor, non-natural Non-naturally occurring opioid, superoxide dismutase, interferon, asparaginase, arginase, trypsin, chymotrypsin, pepsin, DNA, siRNA, oligo Any one selected from DNA can be used.

On the other hand, the present invention includes a method for preparing a non-porous polymer particulate carrier in which a drug is enclosed.

Method for producing a non-porous polymer particulate carrier in which the drug of the present invention is encapsulated

(1) dissolving a hydrophilic polymer to form pores with a biodegradable polyester polymer in an organic solvent,

(2) dispersing and emulsifying the solution containing the polyester-based polymer and the hydrophilic polymer in an aqueous solution containing a hydrophilic surfactant,

(3) removing the organic solvent from the solution containing the polyester-based polymer after emulsification to obtain a porous polymer particulate carrier having a plurality of pores,

(4) encapsulating the drug in the pores of the porous polymer particulate carrier, and then contacting the organic solvent in a vapor state to close the pores of the porous polymer particulate carrier to obtain a non-porous polymeric particulate carrier in which the drug is enclosed.

Figure 1 shows an example of the manufacturing process of the non-porous polymer particulate carrier in which the drug is added to the porous polymer particulate carrier of the present invention as a drug.

Hereinafter, a method for preparing a non-porous polymer microparticle carrier in which the drug of the present invention is encapsulated will be described in more detail by each step.

(1) dissolving a hydrophilic polymer to form pores with a biodegradable polyester polymer in an organic solvent

In the present invention, the biodegradable polyester-based polymer forms the basis of the non-porous high molecular fine carrier in which the drug is encapsulated, and the drug is encapsulated in the pores of the polymer. Biodegradable polyester-based polymer in the present invention may be used as long as it is harmless in the human body and can be slowly degraded and discharged into the body.

As an example of such a biodegradable polyester-based polymer in the present invention, poly-L-lactic acid, poly-glycolic acid, poly-D-lactic acid-co-glycolic acid having an average molecular weight of 500 to 100,000, Any selected from poly-L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, poly-caprolactone, poly-valerolactone, poly-hydroxy butyrate, poly-hydroxy valerate You can use one.

In the present invention, in the case of using a copolymer of lactic acid and glycolic acid in the biodegradable polyester polymer, a copolymer of lactic acid and glycolic acid having a ratio of 10:90 to 90:10 may be used.

As an example of the biodegradable polyester polymer in the present invention, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, or poly-D, L-lactic acid-co-glycolic acid (PLGA) may be used, and more preferably, poly-D, L-lactic acid-co-glycolic acid (PLGA) having a molecular weight of about 5000 to 50,000 is used, and most preferably the ratio of lactic acid to glycolic acid is 75: Poly-D, L-lactic acid-co-glycolic acid (PLGA) having a molecular weight of 8000 to 12,000 can be used.

The pore-forming hydrophilic polymer can be used as long as it has a characteristic of forming a pore in the polymer particulate carrier formed by dissolving in an organic solvent together with the polyester-based polymer and exiting the aqueous phase when contacted with the aqueous solution. Preferably, a hydrophilic / hydrophobic (HLB value) of 10 to 40, an average molecular weight of 500 to 100,000 polymers, a block copolymer of polyethylene glycol and polypropylene glycol derivatives of Pluronic, polyethylene glycol, polyethylene glycol , Or dextran, any one or more selected from bovine serum albumin (BSA) may be used.

Pluronic may use Pluronic L35, Pluronic F127, Pluronic F77, Pluronic F88 or Pluronic F38, having an HLB value of 19 to 31, more preferably molecular weight. It is preferable to use Pluronic F127, Pluronic F77, and Pluronic F88 which are 8000-12000 and whose HLB values are 22-28.

Polyethylene glycol can use the thing of the mean molecular weights 500-100,000, Preferably the thing of the mean molecular weights 10,000-50,000 can be used.

Polyethylene glycol derivatives having an average molecular weight of 500 to 100,000 can be used, preferably methoxy polyethylene glycol (mPEG) having an average molecular weight of 10,000 to 50,000, polyethylene glycol butyl ether, methoxy polyethylene ethylene, methoxy poly oxysiethylene Any one or more selected from carboxylic acid, polyoxyethylene bisamine, polyoxyethylene bisacetic acid, polyoxyethylene bis (6-aminohexyl) can be used.

The hydrophilic polymers may be appropriately selected in consideration of the HLB value and molecular weight, the type and amount of the biodegradable polyester-based polymer used.

In the step (1) of the present invention, any organic solvent may be used as long as it is a solvent having both solubility in the biodegradable polyester-based polymer and the pore-forming hydrophilic polymer. One example of such an organic solvent is selected from methylene fluoride, chloroform, acetone, dimethyl sulfoxide, dimethylformamide, N-methylpyrrolidone, dioxane, tetrahydrofuran, ethyl acetate, methyl ethyl ketone or acetonitrile Either one can be used. Preferably, it is excellent in solubility in both biodegradable polyester polymer and pore-forming polymer, and excellent in ease of removal through evaporation, so that volatile organic solvent methylene fluoride or chloroform, which is easy to form porous polymer fine carrier, can be used. More preferably, methylene chloride is used.

A biodegradable polyester-based polymer and a pore-forming polymer are dissolved together in an organic solvent and then emulsified in an aqueous solution to form a particulate carrier. Therefore, it is possible to obtain a porous particulate carrier as a target only by properly controlling the ratio of the polyester-based polymer serving as a skeleton to contain pores and the polymer serving to directly form pores. Therefore, in the polyester-based polymer and the pore-forming polymer dissolved in the organic solvent, the polyester-based polymer can be dissolved in the organic solvent in the content of 10% by weight to 90% by weight and the pore-forming polymer by 10% by weight to 90% by weight. More preferably, the polyester-based polymer may be dissolved in an organic solvent in an amount of 20% by weight to 30% by weight and the pore-forming polymer in a content of 70% by weight to 80% by weight.

(2) dispersing and emulsifying a solution containing a polyester-based polymer and a pore-forming hydrophilic polymer in an aqueous solution containing a hydrophilic surfactant,

A biodegradable polyester-based polymer and a pore-forming polymer are dissolved together in an organic solvent and emulsified in an aqueous solution to form a particulate carrier.

When dispersing and emulsifying a solution containing a polyester-based polymer and a pore-forming hydrophilic polymer in an aqueous solution, the aqueous solution may include a hydrophilic surfactant so that the pore-forming hydrophilic polymer may come out of the aqueous phase.

Such a hydrophilic surfactant may be used as long as it is highly reactive with the pore-forming hydrophilic polymer to allow the pore-forming hydrophilic polymer to exit the aqueous solution from the polyester-based polymer. In the present invention, any one or more selected from tween, triton, breeze, polyvinylprolidone, and polyvinyl alcohol may be used as one example of such a hydrophilic surfactant.

In the case of using polyvinyl alcohol as the hydrophilic polymer, polyvinyl alcohol may be used in an amount of 0.1 to 5% by weight and having a molecular weight of 13,000 to 23,000, more preferably in an amount of 0.5% by weight and having a molecular weight of 13,000 to 23,000. Can be.

As the pore-forming polymer escapes from the organic solvent onto the aqueous phase, pores are formed. As the organic solvent is removed, the polyester-based polymer is cured to form a skeleton of the particulate carrier. Therefore, depending on the ratio of the organic solvent and the aqueous solution, the escape rate of the pore-forming polymer and the removal rate of the organic solvent in the later step (3) are different, so that the structure of the obtained particulate carrier is changed. Therefore, preferably, the volume ratio of the organic solvent in the volume ratio of the organic solvent and the aqueous solution is 1-20%, the volume ratio of the aqueous solution is 80-99%, more preferably the volume ratio of the organic solvent is 3-10%, the aqueous solution. It is preferable to use formulation conditions in which the volume ratio of is 90 to 97%.

(3) removing the organic solvent from the solution containing the polyester-based polymer after emulsification to obtain a porous polymer particulate carrier having a plurality of pores,

By dissolving the biodegradable polyester polymer and the pore-forming polymer in the organic solvent by the steps (1) and (2), the organic solvent is evaporated / removed while being dispersed / emulsified in an aqueous solution containing a hydrophilic surfactant having an appropriate volume ratio. As a result, the pore-forming polymer exits into the aqueous solution and the polyester-based polymer is cured to form a porous particulate carrier.

By centrifugation and lyophilization, the desired porous biodegradable polymer microcarrier can be obtained. In this case, centrifugation may be performed at 500 to 10,000 rpm for 3 to 30 minutes, frozen at 0 ° C. to −70 ° C., and then dried at 4 to 35 ° C. to obtain porous biodegradable polymer microcarriers.

(4) a step of obtaining a non-porous particulate carrier in which the drug is encapsulated by enclosing the drug in the pores of the porous polymeric particulate carrier and then contacting the organic solvent in a vapor state to close the pores of the porous polymeric particulate carrier.

After the drug is encapsulated in the pores of the porous polymer particulate carrier obtained in step (3), the pores are closed to obtain a non-porous particulate carrier in which the drug is enclosed.

The drug can then be applied to vaccines, hormonal preparations and other hydrophilic therapies that require long-term administration. For example, Human Growth Hormone, Granulocyte Colony-Stiumulating Factor (G-CSF), Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF), Erythropoietin, Vaccines, Antibodies, Insulin, Calcitonin ( calcitonin, adrenocorticotropic hormone (ACTH), glucagon, somatostation, somatotropin, somatomedin, parathyroid hormone, hypothalamus, thyroid hormones, prolactin, and endorphins VEGF (vascular endothelial growth factor), enkephalin, vasopressin, nerve growth factor, non-naturally occurring opioid, superoxide dismutase, Interferon, asparaginase, asparaginase, arginase, trypsin, chymotrypsin, pepsin, DNA, siRNA, oligo DNA can be used any one selected.

The method of injecting a drug to be continuously released into the pores of the biodegradable porous particulate carrier is to prepare a drug to be enclosed in the pores of the particulate carrier in a solution state and disperse the particulate carrier in the drug solution, so that the solution penetrates into the pore structure. Depending on the drug injection method can be used. In addition, any method capable of injecting a drug into the pores, such as a method of directly mixing a drug particle having a size smaller than or equal to the diameter of the porous particulate carrier pores with the porous particulate carrier, is used as the production method of the present invention.

 In the present invention, the method of injecting the drug into the pores of the porous particulate carrier is not limited to the above method, and any method may be used as long as the conventional drug is encapsulated in the particulate carrier.

The drug may be encapsulated in the porous particulate carrier pores and then the pores of the particulate carrier may be closed to obtain a nonporous particulate carrier in which the drug is enclosed. After the drug is sealed, the pores of the particulate carrier are vaporized with an organic solvent, and when the particulate carrier polymer is partially dissolved when reacting with the particulate carrier, the polymers around the pores are fused and the pores of the particulate carrier are gradually reduced, resulting in the pores of the particulate carrier. As it is closed, it is possible to obtain a particulate carrier of the nonporous polymer.

The organic solvent for use in the vapor phase may be any one selected from ethanol, methanol, methylene glolide, chloroform, acetone, dioxane, tetrahydrofuran, ethyl acetate, acetonitrile. Preferably ethanol is the least toxic to the human body and has a weak solubility in the polyester-based polymer and is easily converted to a vapor state.

The vaporized organic solvent and the biodegradable porous particulate carrier can be contacted in a fluidized bed reactor (FBR) (see FIG. 2).

By using a fluidized bed reactor and an organic solvent, the pores of the porous particulate carrier can be closed by the following method.

The biodegradable porous particulate carrier containing the drug is made to be suspended in the air by using a fluidized bed reactor (FBR), which is a device prepared to float in the air. Here, an organic solvent capable of dissolving the polyester polymer is sprayed in a vapor state. By maintaining this state for a suitable time such that the porous particulate carrier becomes a nonporous particulate carrier, the non-porous particulate carrier can be obtained by allowing the pores to be closed while maintaining the form of each individual.

The configuration of the fluidized bed reactor (FBR) is briefly shown in FIG. In order to float the porous fine polymer carrier in the fluidized bed reactor, the pressure of nitrogen gas to be applied must be carefully controlled, and the porous particulate carrier in which the organic solvent vapor formed by injecting nitrogen gas into the organic solvent is suspended. Should be sprayed at a suitable pressure. The vapor of the organic solvent swells the polymer of the particulate carrier and brings it into a rubbery and sticky state. The vaporized organic solvent partially dissolves the porous particulate carrier polymer and the polymers around the porous particulate carrier pores are fused to gradually reduce the pores, eventually closing the pores.

On the other hand, the present invention includes a method of using a drug-releasing agent for continuously releasing a drug-encapsulated nonporous polymer particulate carrier in vivo.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention in more detail, it will be apparent to those skilled in the art that the scope of the present invention is not limited to these examples.

Example 1 Preparation of Porous Biodegradable Polymer Particle Carrier

0.7 g of Pluronic F127 and 0.3 g of poly-D, L-lactic acid-co-glycolic acid (PLGA) having a ratio of lactic acid and glycolic acid of 75:25 and a molecular weight of 10,000 were dissolved in 3 ml of methylene chloride.

The organic solvent in which Pluronic F127 and PLGA were dissolved was added to 7 ml of an aqueous solution containing 0.5% (w / v) polyethylene glycol (88% hydrolyzed, molecular weight 13,000 to 23,000), and the mixture was 90 at 1,500 rpm using a homogenizer. Emulsified for seconds. In order to cure PLGA by removing the organic solvent from the emulsion, the mixture was stirred at 1500 rpm for 4 hours at room temperature and atmospheric pressure. When the hardening of the PLGA formed a porous biodegradable polymer microparticle carrier, the stirring was stopped, the PLGA was centrifuged at 2000 rpm for 10 minutes, washed three times with distilled water, and lyophilized at -20 ° C. Was prepared.

A scanning micrograph of the surface and cross section of the porous particulate carrier prepared above is shown in FIG. 3A. The average diameter of the porous particulate carrier was 52.1 ± 9.9 μm and the average diameter of the pores was 5.5 ± 1.0 μm.

Example 2 Preparation of Nonporous Polymer Particle Carrier Enclosed with Protein Drug (1)

The 400 mg PLGA particulate carrier prepared in Example 1 was dispersed in physiological saline dissolved in human growth hormone at a concentration of 20 mg / ml, and stirred at a low speed of 10 rpm for 2 hours, and the human growth hormone solution into the pore structure of the particulate carrier. It was allowed to penetrate. Then, the particulate carrier was centrifuged at 2000 rpm for 10 minutes and freeze-dried at -20 ° C to prepare a porous polymeric particulate carrier in which human growth hormone was enclosed.

The fluidized bed reactor (FBR) device of FIG. 2 was used to close the pores of the prepared porous polymer particulate carrier containing human growth hormone.

The fluidized bed reactor uses a glass tube with an inner diameter of 24 mm and a height of 660 mm, and a glass filter is installed at the bottom portion so that nitrogen gas for floating the porous particulate carrier is evenly ejected from the bottom of the FBR. In addition, nitrogen gas is injected into the ethanol to make ethanol vapor, and the vaporized ethanol saturated with the vapor is sprayed through a silicon nozzle placed on the glass filter of the reactor. The temperature of the reactor was maintained at 25 ° C. with a water jacket surrounding the reactor.

Arrow in FIG. 2 means the inflow of nitrogen gas.

40 mg of the porous polymer particulate carrier containing the drug was added to the reactor, and nitrogen gas for suspension was injected at a pressure of 0.04 kgf / cm ² . At this pressure, ethanol vapor is sprayed at a pressure of 0.04 kgf / cm ² to the particulate carrier suspended in air. After processing for 10 minutes in this state to recover the non-porous polymer particulate carrier with the pores closed, washed with distilled water and dried.

Scanning micrographs of the surface and cross section of the obtained biodegradable polymeric particulate carrier with closed pores are shown in FIG. 3B. It can be seen that the mean diameter of the particulate carrier with the pores closed is 15.6 W 5.4 μm and the pores are completely closed.

Example 3 Preparation of Nonporous Polymeric Microparticle Carrier Enclosed with Protein Drug (2)

Except for dispersing the 400 mg PLGA particulate carrier prepared in Example 1 in physiological saline dissolved human growth hormone at a concentration of 5 mg / ml in the same manner as in Example 2 containing the human growth hormone A porous polymeric particulate carrier was prepared.

Example 4 Release of Protein Drug of Nonporous Polymeric Microparticle Carrier

In order to confirm that the human growth hormone is continuously released from the biodegradable polymer microparticles containing the prepared drug, the release amount was measured under the following in vitro conditions.

Into the non-porous mirin carrier prepared in Example 1, the porous polymer particulate carrier and 20mg of the drug prepared in Example 2 were encapsulated in the same manner until the pores of the porous polymeric particulate carrier were closed in Example 2. The nonporous polymeric particulate carrier was dispersed in 1.5 ml of saline containing 0.01% (w / v) sodium azide and 0.02% (w / v) Tween20 and placed in a 37 ° C. incubator. .

The amount of protein released by centrifugation of the porous polymer particulate carrier and the non-porous polymeric particulate carrier encapsulated with the drug at 2 days intervals and the supernatant was recovered was measured by a micro-BCA (Microbicinchoninic acid) method.

In order to determine the weight ratio of the protein encapsulated in the particulate carrier, human growth hormone remaining in the particulate carrier after the drug release period was extracted. To this end, 0.5 ml of sodium hydroxide solution at a concentration of 0.5 N was added thereto, and the PLGA was hydrolyzed and dissolved in a 37 ° C. incubator for one day. The total amount of the extracted protein and the released protein was added to measure the total amount of human growth hormone encapsulated in the particulate carrier.

The amount of human growth hormone encapsulated can be controlled by adjusting the concentration of the human growth hormone solution soaking porous particulate carrier.

In the case of the particulate carrier immersed in 5 mg / ml solution of human growth hormone, 3.5 ± 0.1 (w / w)% of human growth hormone was contained in the weight ratio in the state of the porous carrier, and 3.1 ± 0.1 (after closing the pores). w / w)% was included.

In the case of the particulate carrier immersed in a 20 mg / ml solution of human growth hormone, 11.4 ± 0.5 (w / w)% of human growth hormone was contained in the weight ratio in the state of the porous carrier, and 7.0 ± 0.3 (after closing the pores). w / w)% is included. As such, the amount of effective drug in the particulate carrier can be easily adjusted by changing the concentration of the drug solution.

4 shows that human growth hormone is released from the prepared drug-containing biodegradable polymer microcarriers with the change of time.

4A is a graph showing the amount of release of human growth hormone in each of the polymeric microcarriers in which 5 mg / ml of the human growth hormone is encapsulated in the porous polymer microparticle carrier and the nonporous polymeric microparticle carrier.

FIG. 4B is a graph showing the amount of release of human enterohormone with the change of time of each of the macromolecular carriers in which 20 mg / ml of human growth hormone is encapsulated in the porous and nonporous polymer particulate carriers.

In Figure 4 ○ indicates the amount of release of human growth hormone encapsulated in the porous polymer particulate carrier prepared in Example 1, and ● human growth hormone encapsulated in the non-porous polymer particulate carrier prepared in Example 2 It shows the amount of release over time.

As shown in Figure 4, the porous particulate carrier is released in the total amount of human growth hormone encapsulated, but the release rate is very fast, the sustainability of the release is weak. On the other hand, the microparticles with closed pores are continuously controlled release of encapsulated human growth hormone over 40 days.

This tendency was maintained regardless of the amount of human growth hormone encapsulated in the microcarriers, so that the 3.1 carriers with 3.1 ± 0.1 (w / w)% encapsulation had an initial release of only 6.2 ± 1.1%, as shown in FIG. 4A for more than 40 days. It is controlled and released continuously and 80% is obtained.

In addition, in the case of the particulate carrier encapsulated with 7.0 ± 0.3 (w / w)%, as shown in Figure 4B has an initial release of 31.3 ± 1.4% continuously controlled release over 40 days, 80% of the present invention, Example 2 of the present invention The particulate carrier prepared by was found to be a very good formulation for sustained release of the drug.

As can be seen in Example 4, the non-porous polymeric microcarrier containing the drug of the present invention is capable of sustained controlled release of the drug as well as the non-porous polymeric microcarrier in which the drug is encapsulated. No aqueous interface occurs and no harsh conditions occur that denature the properties of protein drugs.

Claims (13)

A non-porous polymer particulate carrier in which a drug is encapsulated in a pore of a microcarrier made of a biodegradable polyester-based polymer, and then a drug capable of continuously releasing the drug in which the pore is closed using an organic solvent vapor. The method of claim 1, wherein the biodegradable polyester-based polymer is poly-L-lactic acid, poly-glycolic acid, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid-co The drug is characterized in that any one selected from -glycolic acid, poly-D, L-lactic acid-co-glycolic acid, poly-caprolactone, poly-valerolactone, poly-hydroxy butyrate, poly-hydroxy valerate Enclosed nonporous polymeric particulate carrier. delete The method of claim 1, wherein the organic solvent is any one selected from ethanol, methanol, methylene fluoride, chloroform, acetone, dioxane, tetrahydrofuran, ethyl acetate, acetonitrile, non-porous polymeric microparticles encapsulated drug carrier. (1) dissolving a hydrophilic polymer to form pores with a biodegradable polyester polymer in an organic solvent, (2) dispersing and emulsifying the solution containing the polyester-based polymer and the hydrophilic polymer in an aqueous solution containing a hydrophilic surfactant, (3) removing the organic solvent from the solution containing the polyester-based polymer after emulsification to obtain a porous polymer particulate carrier having a plurality of pores, (4) a method for producing a non-porous polymer microparticle carrier, in which a controlled release of the drug can be achieved by enclosing the drug in the pores of the porous polymer microparticle carrier and then contacting the organic solvent in a vapor state to close the pores of the porous polymer microparticle carrier. . The biodegradable polyester-based polymer according to claim 5, wherein the biodegradable polyester-based polymer is poly-L-lactic acid, poly-glycolic acid, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid-co -Glycolic acid, poly-D, L- lactic acid-co-glycolic acid, poly-caprolactone, poly-valerolactone, poly- hydroxy butyrate, poly-hydroxy valerate . delete The organic solvent of claim 5, wherein the organic solvent of step (1) is methylene chloride, chloroform, acetone, dimethyl sulfoxide, dimethyl formamide, N-methylpyrrolidone, dioxane, tetrahydrofuran, ethyl acetate, Process for producing any one selected from methyl ethyl ketone or acetonitrile. The method of claim 5, wherein the hydrophilic surfactant is any one selected from tween, triton, breeze, polyvinylprolidone, and polyvinyl alcohol. The method of claim 5, wherein the organic solvent for use in the vapor phase in step (4) is any one selected from ethanol, methanol, methylene glolide, chloroform, acetone, dioxane, tetrahydrofuran, ethyl acetate, acetonitrile Characterized in the manufacturing method. The method according to claim 5, wherein the organic solvent in the vapor phase of step (4) and the biodegradable porous particulate carrier are contacted in a fluidized bed reactor. delete Claims 1, 2 and 4, wherein the non-porous polymeric microparticle carrier containing the drug of any one of the selected from the method of using as a drug release agent to continuously release in vivo.

Images