KR100752702B1 - Biodegradable polymer nanoparticles and method for preparing the same - Google Patents

Abstract

Provided are biodegradable polymer nanoparticles which contain a large quantity of a protein having affinity to heparin or antibody, and release the protein for a certain period of time without loss of physiological activity and initial burst of the protein, and a method for preparing the same nanoparticles. The biodegradable polymer nanoparticles contain polyester-based polymer nanoparticles and heparin or antibody immobilized to the polymer nanoparticles, and have the average diameter of 1-1000 nm and micropores in the surface, wherein the polyester polymer is polylactic acid, polyglycolic acid, polylactide-co-glycolide, polycaprolactone, polyvalerolactone, polyhydroxy butyrate, polyhydroxy valerate and a mixture thereof. A sustained release agent contains the biodegradable polymer nanoparticles and a drug such as protein or peptide.

Description

Biodegradable polymer nanoparticles and its manufacturing method {BIODEGRADABLE POLYMER NANOPARTICLES AND METHOD FOR PREPARING THE SAME}

1 is a scanning electron micrograph of heparin-immobilized polyester-based polymer nanoparticles prepared according to Example 1. FIG.

Figure 2 shows the particle size distribution of heparin-immobilized polyester-based polymer nanoparticles prepared according to Example 1.

Figure 3 is a graph showing the drug release behavior of basic fibroblast growth factor from heparin-immobilized biodegradable polymer nanoparticles prepared according to Example 2.

Figure 4 is a graph showing the drug release behavior of β-nerve growth factor from heparin-immobilized biodegradable polymer nanoparticles prepared according to Example 2.

The present invention relates to a biodegradable polymer nanoparticles and a method for producing the same, and more particularly, to a biodegradable polymer nanoparticles immobilized heparin or antibody capable of continuously controlled drug release and a method for producing the same.

Conventionally, a method for preparing a sustained-release drug delivery system (DDS) preparations is known as coacervation method, emulsion phase separation method, encapsulation by spray drying, and solvent evaporation in organic or aqueous phase. Among these methods, the solvent evaporation method in water phase is the most widely used, which is largely classified into a double emulsion evaporation method and a single emulsion evaporation method.

In general, the double emulsion evaporation method used for encapsulating a water-soluble drug such as a peptide or a protein is formed by dissolving a drug-containing aqueous solution prepared by dissolving the drug in an aqueous solution in an organic solvent containing a biodegradable polymer to form a primary emulsion. It is a method to disperse in an aqueous phase. This method is a method in which the organic solvent is removed by extraction or evaporation in the process of dispersing the polymer in the organic solvent in the water phase, so that the solubility of the polymer is reduced, so that the microspheres are formed. In general, the microspheres prepared by the double emulsion evaporation method is characterized by the fact that drugs such as peptides and proteins are reduced in bioactivity because the organic solvent is used when the drug is contained in the microspheres.

It is difficult to precisely control the release of the drug for a certain period of time in a formulation in which the drug is encapsulated in the microsphere using the biodegradable microsphere as a carrier, because the initial overrelease of the drug occurs. The initial overrelease of the drug is caused by the diffusion of the drug rather than by the degradation mechanism of the biodegradable polymer carrier. In particular, the initial over-release of such drugs is a greater problem in the case of hydrophilic drugs such as peptides and proteins, and researches on various microspheres and film production methods to solve this problem.

In addition, the introduction of macromolecular compounds such as peptides and proteins into the microspheres has various problems as compared with compounds having a small molecular weight. Specifically, due to the interaction between the polymer and the peptide or protein, the peptide or protein is difficult to homogeneously disperse in the polymer microspheres, and due to the low solubility, a more complicated and difficult mixing process is required in the mixing of the aqueous solution and the organic solvent in the preparation of the microspheres. Done. In addition, it is known that the amount of drug introduced is reduced and a very irregular carrier is produced, and that the stability of the drug is more likely to change with temperature or pH change than that of a low molecular weight drug.

It is an object of the present invention to provide biodegradable polymer nanoparticles that can release a drug continuously for a period of time without initial overrelease.

Another object of the present invention is to provide a method for producing the biodegradable polymer nanoparticles.

Another object of the present invention is that, unlike the conventional drug release system using an organic solvent to suture the drug into the microspheres, the drug physiological activity of the drug is reduced, the drug continues for a period of time without a decrease in the biological activity of the peptide or protein. It is to provide a sustained release formulation comprising a biodegradable polymer nanoparticles that can release.

In order to achieve the above object, the present invention provides a biodegradable high molecular nanoparticle comprising a polyester-based polymer nanoparticles and heparin or an antibody immobilized on the polymer nanoparticles. The heparin or antibody is bound to the biodegradable polymer nanoparticles through chemical covalent bonds.

The present invention also provides a method for producing biodegradable polymer nanoparticles for preparing polyester-based polymer nanoparticles, and immobilizing heparin or antibodies on the surface of the nanoparticles.

The present invention also provides a sustained release formulation comprising a biodegradable polymer nanoparticles and a drug in which the heparin or antibody is bound to the surface.

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

In the biodegradable polymer nanoparticles of the present invention, heparin or an antibody is immobilized on the surface of a polyester-based polymer nanoparticle having one or more functional groups.

The material of the polyester-based polymer nanoparticles is polylactic acid, polyglycolic acid, polylactide-co-glycolide, polycaprolactone, polyvalerolactone, polyhydroxy butyrate, and polyhydroxy valerate in the group At least one selected, more preferably polylactide-co-glycolide (PLGA). The polymer may be degraded in vivo and thus may be usefully used in drug delivery systems.

In the present invention, the "biodegradable polymer nanoparticles" means microspheres made of biodegradable polymers having a number average molecular weight of 1,000 to 1000,000 having functional groups that are compatible with heparin or an antibody at the terminal. The diameter of the microspheres is 1 to 1000 nm, preferably 10 to 1000 nm, more preferably 10 to 800 nm, even more preferably 10 to 500 nm. When the diameter of the microspheres is less than 1 nm, it is difficult to prepare, and when the diameter of the microspheres exceeds 1000 nm, the amount of heparin or antibody that can be bound is small because of the small surface area per unit weight.

The heparin or antibody is preferably connected to the surface of the polymer nanoparticles by covalent bonds. The covalent bonds also include those in which a moiety is covalently bonded directly to each other or indirectly through another spacer, linker, or multiligand. As the spacer or linker, polyalkylene glycol or the like may be used. Here, the polyalkylene glycol preferably includes alkylene having 2 to 100 carbon atoms, and preferred examples thereof include polyethylene glycol or polypropylene glycol. Covalent bonds between polyester-based polymer nanoparticles and heparin or antibodies can be broken by natural hydrolysis and enzymes.

The polyester-based polymer nanoparticles and heparin or the antibody may be combined in a molar ratio of 1: 1000 to 1: 0.001, preferably in a molar ratio of 1:10 to 1: 1. This molar ratio may be used as the molar ratio to obtain the maximum binding rate with the minimum heparin or antibody, depending on the type of drug and coupling agent. When the molar ratio of heparin or antibody to the polymer nanoparticles is less than 0.001, sufficient sustained release of the polymer nanoparticles may not be obtained. When the molar ratio of heparin or antibody is greater than 1000, it is not preferable to use heparin or an antibody excessively.

In the present invention, since the nano-sized particles are used, the binding rate of heparin or antibodies can be increased while using a small amount of polymer.

Micropores may be formed on the surface of the biodegradable polymer nanoparticles.

The polyester polymer nanoparticles to which the heparin or antibody is immobilized are prepared as follows.

First, a biodegradable polyester-based polymer is prepared. Polyester-based polymer may be prepared by the synthesis method of the general polyester polymer.

The synthesis method of the polylactide-co-glycolide in the polyester-based polymer is described as follows. Polylactide-co-glycolide is prepared by ring-opening polymerization of lactide and glycolide, and polylactide-co-glycolide is dissolved in an organic solvent in order to remove unreacted monomer and initiator from the copolymer. Purify by precipitation in non-solvent. Chloroform, methylene chloride, or a mixture thereof may be used as the organic solvent. The non-solvent may be used a solvent selected from the group consisting of methanol, ethanol, hexane, ether and mixtures thereof. Preferably, the polymerization reaction is carried out for about 12 to 24 hours.

Lactide is the presence of L-lactide, D-lactide and D, L-lactide isomers.In the ring-opening polymerization of lactide and glycolide, tin chloride, octosan tin oxide, tin oxide, zinc chloride, and oxidation Although a catalyst such as zinc can be used, octosan tin, which is approved by the US FDA, is most widely used for the synthesis of biodegradable polymer materials for the production of L-lactide and glycolide, which are biocompatible.

By controlling the ratio of L-lactide, glycolide and initiator, which are monomers in the polymerization reaction, polylactide-co-glycolide having various molecular weights can be prepared, and also of high molecular weight polylactide-co-glycolide Manufacturing is possible.

The ring-opening polymerization reaction of lactide and glycolide may be a bulk polymerization method, a solution polymerization method, or a suspension polymerization method, but the ring-opening polymerization is performed by a bulk polymerization method in a molten state in consideration of the prevention of mixing of organic solvents and suspension stabilizers. The reaction is preferred. The reaction temperature of aliphatic polyester, such as lactide and glycolide, is most suitable about 130 to 180 ℃, transesterification reaction occurs above 200 ℃ can not form a polymer of the desired structure.

After the reaction, the polylactide-co-glycolide dissolves very well in the organic solvent, and this solution can be effectively removed by removing the unreacted monomer and initiator by extracting from the non-solvent.

On the other hand, the functional group at the end of the polylactide-co-glycolide obtained is a hydroxy group, and the number of such functional groups can be adjusted according to the kind of initiator used at the time of synthesis. As such an initiator, an alcohol having a hydroxyl group at the terminal may be preferably used. Specifically, dodecanol, 1,6-hexanediol, decandiol, pentaerythritol, dipentaerythritol, tripentaerythritol, and the like can be given. have. 1,6-hexanediol in the above initiator is a dihydric alcohol having two hydroxyl groups, and both ends of the polylactide-co-glycolide produced after the reaction can be derived to a hydroxyl group.

The polymerization reaction of polylactide-co-glycolide using tin octosan as a catalyst and 1,6-hexanediol as an initiator is shown in Scheme 1 below.

 Lactide Glycolide Polylactide-co-glycolide

The method of immobilizing heparin or an antibody on the surface of the polyester-based polymer nanoparticles thus prepared is as follows.

For example, an amine group may be introduced at the terminal of the polyester-based polymer nanoparticle to covalently bond the amine group of the biodegradable nanoparticle to the carboxyl group of the heparin or the antibody using a coupling agent. Such a method of covalently binding the polyester-based polymer nanoparticles and heparin or the antibody, after activating the carboxyl group of the heparin or antibody, reacts with the amine groups of the polyester-based polymer nanoparticles are bonded to the polymer through an amide bond.

Specifically, the method of binding through amide bonds first preactivates heparin or an antibody. The preactivation of heparin or antibody is to selectively bind the carboxyl group of heparin or antibody to the amine group of the polyester-based polymer nanoparticles. It is activated for 1 to 4 hours at 0 to 25 ° C by addition.

After activating the heparin or the antibody as described above, it is added to the dispersion in which the polyester polymer nanoparticles are dispersed and amidated to covalently bond the polyester polymer nanoparticle with the heparin or antibody. Covalently bound polyester-based polymer nanoparticles-heparin or antibodies are purified through a series of procedures. The purification process may be a centrifugation process or the like.

The polyester-based polymer nanoparticles and heparin or an antibody may be bonded through an ester bond, an unhydride bond, a carbamate bond, a carbonate bond or an imine bond in addition to an amide bond. Since the ester bond is to bind the hydroxyl group of the terminal of the polyester-based polymer nanoparticles and the carboxylic acid group of heparin or the antibody, it is not necessary to go through the step of replacing the terminal of the polymer nanoparticles with an amine group.

As a method of introducing a highly reactive functional group such as an amine group into the terminal of the polyester-based polymer nanoparticles, a protecting group may be introduced into the first terminal and then the protecting group may be removed, and then an amine group may be introduced into the highly reactive functional group.

The step of introducing the protecting group is carried out by reacting a compound containing a protecting group and a coupling agent with a polyester-based polymer. Examples of the coupling agent include 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide (EDC), dicyclohexyl carbodiimide (DCC), bis (2-oxo-3-oxazolidinyl) phosphonic chloride ( BOB-Cl), disuccinimidyl carbonate (DSC), diisopropyl carbodiimide (DIPC), N-hydroxysuccinimide (NHS), or a mixture thereof. In the process of removing the protecting group, a weak acid such as trifluoroacetic acid or a strong acid such as sulfuric acid, hydrochloric acid, nitric acid, acetic acid, or the like may be used.

As the basic catalyst, one selected from triethylamine, N, N-dimethylaminopyridine, pyridine, N-methylmorpholine, and N, N-diisopropyl ethylamine can be used.

The introduction reaction of the amine group is preferably carried out in a solvent such as chloroform, methylene chloride, N, N-dimethylformamide, tetrahydrofuran, dimethyl sulfoxide, 1,4-dioxane and the like.

Referring to the process of introducing an amine group to the terminal of the polyester-based polymer using polylactide-co-glycolide as an example, it is shown in Scheme 2 below. First, t-Boc-glycine is introduced into the terminal group of the polylactide, and then, a terminal t-Boc group is removed to substitute the amine group.

As shown in Scheme 2, a hydroxyl group is present at the terminal of the polylactide-co-glycolide, and the hydroxy group and t-Boc-glycine are coupled to each other using dicyclohexyl carbodiimide (DCC) as a coupling agent. t-Boc-glycine may be introduced. Coupling agents used in this process may include 1- (3-dimethyl aminopropyl) -3-ethylcarbodiimide (EDC), dicyclohexyl carbodiimide (DCC), etc. The highest reaction rate was obtained when DCC and N, N-dimethyleneaminopyridine (DMAP) were used simultaneously.

The polylactide-co-glycolide whose terminal is t-Boc-glycine is reacted with trifluoroacetic acid to remove the t-Boc protecting group and to replace the terminal with an amine group. At this time, anhydrous methylene chloride is used as the solvent and reacted at 25 ° C. for 3 hours.

The polylactide-co-glycolide copolymer prepared in this manner was obtained in a quantitative yield of 90% or more, and the substitution reaction of the terminal group through the reaction of each functional group was confirmed by ¹ H-NMR measurement. .

As a method for nanoparticle-forming a polylactide-co-glycolide copolymer in which the terminal is substituted with an amine group, a conventional oil in water (O / W) monoemulsion method may be used.

Sustained release preparations comprising a biodegradable polyester-based polymer nanoparticle prepared by combining a polyester-based polymer nanoparticle having a highly reactive functional group with an activated heparin or an antibody and a pharmacologically active ingredient can be prepared.

Existing drug delivery system has a problem in that the drug activity is greatly reduced because the organic solvent is used to seal the drug in the polymer microspheres that exhibit acidity when biodegradable. In contrast, the drug delivery system of the present invention binds the drug to the surface of the polymer nanoparticles without sealing the drug in the microspheres and without using an organic solvent, thereby greatly reducing drug activity and preventing the initial over-release of the drug. have.

The pharmacologically active ingredient may be used as long as it is a protein having affinity with heparin or an antibody, and in particular, growth factors may be preferably used. Specific examples of the growth factor include base fibroblast growth factor, β-nerve growth factor, vascular endothelial growth factor, transforming growth factor-β, bone morphogenic protein, and the like. . The sustained release preparation of the present invention can be usefully used for the treatment of ischemic diseases such as myocardial infarction and Burger's disease, and can be effectively used for blood vessel regeneration and bone regeneration.

Such pharmacologically active ingredients may be present in dispersions, particles, granules, or powders. In addition, the pharmaceutically active ingredient may further comprise a binder, dispersant, emulsifier or wetting agent, dyes, and the like. Other excipients such as lactose, magnesium stearate, microcrystalline cellulose, starch, stearic acid, calcium phosphate, glycerol monostearate, sucrose, polyvinylpyrrolidone, gelatin, methylcellulose, sodium carboxymethylcellulose, sorbitol , Mannitol, polyethylene glycol, and other ingredients typically used as stabilizers or used in drug formulations. The carrier may be used in an amount of 0 to 80% by weight based on the total amount of the sustained-release preparation, if necessary.

The pharmacologically active ingredient is present in 1 to 70% by weight of the total amount of the sustained release preparation. If the amount of the pharmacologically active ingredient is less than 1% by weight, the amount of granules to be administered should be large due to the low concentration of the active substance, and if the amount exceeds 70% by weight, it is difficult to control the sustained release.

Sustained release formulations of the present invention may be prepared by mixing biodegradable nanoparticles in which pharmacologically active ingredients are combined with heparin or antibodies.

The formulation is generally prepared in the form of tablets, dragees, hard or soft capsules and the like. If the formulations are tablets, coated tablets, dragees and hard capsules, lactose, corn starch or derivatives thereof, talc, stearic acid or salts thereof can be used. Also in the case of soft capsule formulations, polyols of vegetable oils, waxes, fats, semisolids and liquids can be used.

The method of administration can be readily selected according to the dosage form and can be administered orally or parenterally. The dosage may vary depending on the weight, severity, sex, and age of the patient, but in the case of a healthy adult male, the dosage is preferably 1 μg / kg to 10 mg / kg per day. The number of doses can also be easily adjusted according to the weight, severity, sex, and age of the patient.

It is understood that the sustained release formulation of the present invention exhibits a zero-order release of the active ingredient, thereby effectively controlling the release rate of the effective drug, thereby maintaining a locally constant concentration of the active drug. have. Of course, the heparin or antibody-immobilized nanoparticles according to the present invention is biodegradable and is naturally biodegradable and absorbed in the human body after drug release, so that no additional procedure for removing the used agent is necessary.

Hereinafter, described in detail based on the embodiment of the present invention as follows, the present invention is not limited by the embodiment.

Example 1

Into a dried 500 mL glass ampoule, 100 g (0.6944 mole) of L-lactide and 80 g (0.6944 mole) of glycolide were added, 2.8007 g (0.0069 mole) of octosan tin as a catalyst and 1.2543 g (0.0106 mole) as an initiator. ) Was added 1,6-hexanediol. The Teflon-coated magnetic bar was placed in an ampoule, and the ampoule containing the reactant was vacuumed at 0.01 mmHg for 2 hours to remove water and injected with dry nitrogen.The process was repeated five times, and the ampoule was heated under a torch lamp under vacuum. Sutured.

The sealed ampoule was placed in an oil bath at 150 ° C. and stirred to proceed polymerization for 24 hours. As the polymerization proceeded, the polymerization system became more viscous, and stirring became impossible. After the reaction was completed, the ampoule was cooled using liquid nitrogen and then destroyed to recover the polymer. The recovered sample was dissolved in chloroform and precipitated in methanol to remove the catalyst, the unreacted monomer and the low molecular weight polymer. The sample obtained was vacuum dried at room temperature for at least 24 hours.

The obtained polymer was white in color, and the yield was obtained at quantitative value of 95% or more. Hydrogen ( ¹ H) nuclear magnetic resonance analysis confirmed that lactide and glycolide were ring-opened by the initiator, and that hydroxyl groups were introduced at both terminal groups. It was confirmed through the integration ratio of the terminal group and the monomer that the number average molecular weight is about 50000.

In a 500 mL flask, 9.00 g (0.0003 mol) of polymerized polymer and 0.9023 g (0.003 mol) / DCC of t-Boc-glycine were added respectively, and 0.9319 g (0.0076 mol) of DMAP was added as a catalyst. 100 mL of methylene chloride was used as the solvent and allowed to react at room temperature for 24 hours. After reaction, precipitated in methanol to remove t-Boc-glycine and catalyst. The sample obtained was vacuum dried at room temperature for at least 24 hours. Hydrogen ( ¹ H) nuclear magnetic resonance analysis after the reaction confirmed that t-Boc-glycine was introduced at the end.

4.50 g (0.00015 mol) of the obtained product in a 500 mL flask were reacted with 50 mL of methylene chloride and 50 mL of trichloroacetic acid at room temperature for 3 hours, and then precipitated in methanol. The sample was vacuum dried at room temperature for at least 24 hours. It was. Hydrogen ( ¹ H) nuclear magnetic resonance analysis after the reaction confirmed that the amine group was introduced at the end. For the production of PLGA polymer nanoparticles using the obtained product, an oil in water (O / W) single emulsification method was used.

1 g of PLGA dissolved in 10 ml of methylene chloride was prepared using an ultrasonic cleaner in 100 ml of distilled water for 15 minutes using 3% (w / v) of polyvinyl alcohol (molecular weight 30,000 to 70,000) as a surfactant. Sonicator, S-450D, Branson). Then, methylene chloride was evaporated into air by stirring at room temperature and atmospheric pressure for 12 hours. After this process, the hardened nanoparticles were collected by centrifugation at 15000 rpm for 20 minutes, washed five times with distilled water, and freeze-dried. The SEM image of the PLGA polymer nanoparticles thus obtained is shown in FIG. 1. As shown in FIG. 1, the average diameter of the PLGA polymer nanoparticles was found to be 160 nm.

Figure 2 shows the particle size distribution of the PLGA polymer nanoparticles prepared according to Example 1. As shown in FIG. 2, the particle size was found to be 100 to 250 nm.

Example 2

Biodegradable polymer nanoparticles were prepared using the star polylactide-co-glycolide in the same manner as described in Example 1, except that dipentaerythritol was used as the initiator.

Example 3

1 g of the nanoparticles prepared by the single emulsification method in Examples 1 and 2 was dispersed in 50 mL MES buffer, and then 100 mg of heparin was dissolved, followed by 1- (3-dimethyl aminopropyl) -3-ethylcarbide. (EDC), N-hydroxysuccinimide (N-Hydroxysuccinimide; NHS), and N, N-dimethyleneaminopyridine (DMAP) were added and stirred for 5 hours to proceed with the reaction. Heparin-immobilized biodegradable nanoparticles were obtained by centrifugation for 10 minutes using an ultrafast centrifuge, and washed with distilled water five times or more to remove unreacted materials.

10 mg of heparin-immobilized polyester-based nanoparticles were dispersed in 3 mL of toluidine blue 5% solution and stirred for 30 minutes. Thereafter, 3 mL of normal hexane was added thereto, followed by stirring for 1 minute, and then the nanoparticle-heparin-toluidine blue complex was removed by centrifugation. Absorbance was measured at 631 nm using a UV spectrometer to calculate the concentration of heparin immobilized on the nanoparticle surface. The results are shown in Table 1 below.

TABLE 1

Initiator Number average molecular weight Amount of immobilized heparin Example 1 1,6-hexanediol 49,000 0.535 mg / g Example 2 Dipentaerythritol 53,000 4.894 mg / g

In the results of Table 1, heparin was fixed to the polymer.

Comparative Example 1

1 g of PLGA prepared in Example 1 was dissolved in 10 ml methylene chloride, and 15% in 100 ml of distilled water using 3% (w / v) of polyvinyl alcohol (molecular weight 30,000-70,000) as a surfactant. Stirred with 700 rpm stirrer for a minute to emulsify. Then, the mixture was stirred at room temperature and atmospheric pressure for 12 hours to evaporate methylene chloride into air. Through this process, the hardened microparticles were separated and collected with a filter of 40 to 70 μm, washed with distilled water over five different sizes, and lyophilized to prepare 40 to 70 μm PLGA microparticles.

Experimental Example 1

To investigate the drug release behavior from the heparin-immobilized nanoparticles, 14 mg of the heparin-immobilized nanoparticles obtained in Example 2 and 4 μg of a base fibroblast growth factor compatible with heparin were bound at 4 ° C. for 120 minutes. After 5 mL 37 ℃, the release of the drug in phosphate buffer solution (PBS) was measured five times using the immunoassay (ELISA), the results are shown in FIG. As shown in Figure 3, the base fibroblast growth factor from the heparin-immobilized nanoparticles prepared according to the present invention exhibits near zero-order release for about 15 days to effectively control the release rate of the effective drug. It can be seen that the concentration of the effective drug can be kept locally constant.

Experimental Example 2

The release behavior was examined in the same manner as described in Experiment 1, except that β-nerve growth factor was used as the growth factor. The results are shown in FIG. As shown in FIG. 4, β-nerve growth factor from heparin-immobilized nanoparticles prepared according to the present invention exhibits near zero-order release for about 15 days to effectively control the release rate of an effective drug. It can be seen that the concentration of the effective drug can be kept constant locally.

Experimental Example 3

In order to determine the relationship between the particle size of PLGA and the amount of growth factor protein, the amount of the maximum growth factor protein that can be contained in the PLGA nanoparticles of Example 1 and the PLGA microparticles of Comparative Example 1 was measured. 10 mg each of the obtained heparin-immobilized PLGA nanoparticles and PLGA microparticles, and basic fibroblast growth factors 0.2, 1, 5, 10, 20, 50, 70, 100, and 150 μg, respectively, at 120 ° C. in a phosphate buffer solution for 120 minutes. After binding, the amount of unbound base fibroblast growth factor remaining in the supernatant by centrifugation at 15000 rpm for 20 minutes was measured by immunoassay (ELISA) five times. The results are shown in Table 2.

TABLE 2

Amount of Base Fibroblast Growth Factor Initially Used (μg) 0.2 One 5 10 20 70 100 150 Amount of Unbound Base Fibroblast Growth Factor (μg) Example 1 0.0 0.0 0.0 0.0 0.0 0.2 5.5 57.1 Comparative Example 1 0.0 0.7 4.8 9.7 19.9 69.8 99.7 149.8

As shown in Table 2, PLGA nanoparticles may contain more growth factor proteins on the surface than PLGA microparticles.

As described in detail above, when heparin or antibody according to the present invention is developed for use in drug delivery to the surface-immobilized biodegradable nanoparticles, heparin or antibody is biodegradable by mixing only the biodegradable nanoparticles and growth factors immobilized The growth factor can be combined with sex nanoparticles to reduce the bioactive degradation of drugs that can occur during the preparation of microspheres encapsulated with existing drugs, and also reduce the initial release rate of drugs.

Claims (10)

Polyester-based polymer nanoparticles, and Heparin or antibody immobilized on the polymer nanoparticle Biodegradable polymer nanoparticles comprising a; And Sustained release preparations comprising the drug. The sustained-release preparation of claim 1, wherein the nanoparticles have an average diameter of 1 to 1000 nm. The method of claim 1, wherein the polyester-based polymer is polylactic acid, polyglycolic acid, polylactide-co-glycolide, polycaprolactone, polyvalerolactone, polyhydroxy butyrate, polyhydroxy valerate and their Sustained release formulations selected from the group consisting of mixtures. The sustained-release preparation according to claim 1, wherein micropores are formed on a surface of the biodegradable polymer nanoparticles. The sustained-release preparation according to claim 1, wherein the polyester-based polymer and heparin or antibody are bound in a molar ratio of 1: 1000 to 1: 0.001. delete delete delete delete The sustained release formulation of claim 1, wherein the drug is a protein or a peptide.

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