Polylactic acid microcapsules

A method of the preparation of polylactic acid microcapsules of controlled particle size and drug loading, J. Microencapsul.,... 

Lin, S. Y., Ho, L. T., Chiou, H. L., Microencapsulation and controlled release of insulin from polylactic acid microcapsules. Biomater. Med. Devices Artif. Organs. 86, 187, 1985. 

Itoh, M., Nakano, M., and Juni, K. Sustained release of sulfamethizole, 5-flourouracil, and doxorubicin from polylactic acid microcapsules. Chem. Pharm. Bull. 28(4) 1051-1055, 1980. 

Ogawa Y, Yamamoto M, Okada H, Yashiki T, Shimamoto T. A new technique to efficiently entrap leuprolide acetate into microcapsules of polylactic acid or copolyflactic glycohc) acid. Chem Pharm Bull 1988 36 1095-1103. 

Ogawa, Y., et al. In vivo release profiles of leuprolide acetate from microcapsules prepared with polylactic acids or copoly(lactic/glycolic) acids and in vivo degradation of these polymers. Chem. Pharm. Bull. (Japan), 1988, 36, 2576-2581. 

In an early study by Lin et al., insulin-loaded polylactic acid (PLA) microcapsules were synthesized by an emulsification-solvent evaporation process originally reported by Beck et al. Several parameters in the synthesis process were modified with the intention of optimizing the insulin release profile. Such modifications included variations in types, concentrations, and viscosities of protective colloids used in the emulsification process. Polyvinyl alcohol (PVA), when used as the protective colloid in the fabrication process, was found to produce the PLA microparticles in reproducible quality. Further studies revealed that the concentration PVA directly affects the PLA particle size and the surface characteristics of the microcapsules. With higher concentrations of PVA, microparticles tended to be smaller and to have a smoother surface. When the release profiles of the microcapsules were stud-... 

Ogawa Y, Yamamoto M, Takada S, Okada H, Shimamoto T. Controlled-release of leuprolide acetate from polylactic acid or copoly(lactic/glycolic) acid microcapsules Influence of molecular weight and copolymer ratio of polymer. Chemical and Pharmaceutical Bulletin. April 1988 36(4) 1502-1507. PubMed PMID 3138032. 

Tsai DC, Howard SA, Hogan TF, Malanga CJ, Kandzari SJ, Ma JK. Preparation and in vitro evaluation of polylactic acid-mitomycin C microcapsules. Journal of Microencapsulation. July-September 1986 3(3) 181-193. PubMed PMID 3149671. 

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