title: Control of drug loading efficiency and drug release behavior in preparation of hydrophilic-drug-containing monodisperse PLGA microspheres.
abstract: We prepared monodisperse poly(lactide-co-glycolide) (PLGA) microspheres containing blue dextran (BLD)--a hydrophilic drug--by membrane emulsification technique. The effects of electrolyte addition to the w(2) phase and significance of the droplet size ratio between primary (w(1)/o) and secondary (w(1)/o/w(2)) emulsions during the preparation of these microspheres was examined. The droplet size ratio was evaluated from the effect of stirring rate of the homogenizer when preparing the primary emulsion. The drug loading efficiency of BLD in these microspheres increased with stirring rate. It increased to approximately 90% when 2.0% NaCl was added to the w(2) phase. Drug release from these microspheres was slower than that when they were prepared without electrolyte addition. Despite the very high efficiency drug release was gradual because BLD was distributed at the microspheres core. Relatively monodisperse hydrophilic-drug-containing PLGA microspheres with controlled drug loading efficiency and drug release behavior were prepared.
authors.affiliation: Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, 1-1 Minami-ohsawa, Hachioji, Tokyo, 192-0397, Japan. fuminoito@spice.ocn.ne.jp
authors.forename: Fuminori
authors.initials: F
authors.lastname: Ito
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Fujimori
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Honnami
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Kawakami
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kanamura
authors.forename: Kimiko
authors.initials: K
authors.lastname: Makino
mesh_terms: D003911:Dextrans; D004655:Emulsions; D006878:Hydroxides; D019344:Lactic Acid; D008863:Microspheres; D010087:Oxides; D004364:Pharmaceutical Preparations / Q000008:administration & dosage*; D011098:Polyglactin 910; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer
chemical_list: D003911:Dextrans; D004655:Emulsions; D006878:Hydroxides; D010087:Oxides; D004364:Pharmaceutical Preparations; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D011098:Polyglactin 910; C017080:blue dextran