title: Effect of gamma-sterilization process on PLGA microspheres loaded with insulin-like growth factor-I (IGF-I).
abstract: The influence of gamma-sterilization on the physicochemical properties of a controlled release formulation for the insulin-like growth factor-I (IGF-I) was investigated in this study. Recombinant human insulin-like growth factor-I (rhIGF-I) was efficiently entrapped in poly (D,L-lactide-co-glycolide) (PLGA) microspheres by water-in-oil-in-water (W/O/W) solvent evaporation technique. Microspheres were irradiated at a dose of 25kGy and evaluated by means of scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The stability of the released protein was investigated by circular dichroism (CD) and sodium dodecyl sulfate polyacrilamide gel electrophoresis (SDS-PAGE). No difference was noticed in microsphere size and morphology before and after irradiation. Drug loading remains essentially the same after the sterilization process. However, rhIGF-I aggregation was detected by electrophoresis. In addition, subtle changes in DSC pattern were noticed for irradiated microspheres. In vitro drug release from irradiated microspheres was also affected, showing an increased burst effect. From this results it can be concluded that gamma-sterilization process causes changes in the properties of rhIGF-I loaded microspheres.
authors: Departamento de Farmacia y Tecnologia Farmacéutica, cultad de Farmacia Plaza Ram6nóy Cajal E-28040 Madrid, Spain.
authors: C
authors: C
authors: Carrascosa
authors: L
authors: L
authors: Espejo
authors: S
authors: S
authors: Torrado
authors: J J
authors: JJ
authors: Torrado
mesh_terms: D003692:Delayed-Action Preparations / Q000737:chemistry* / Q000528:radiation effects*; D004355:Drug Stability; D005720:Gamma Rays; D007334:Insulin-Like Growth Factor I / Q000737:chemistry* / Q000528:radiation effects*; D019344:Lactic Acid / Q000737:chemistry* / Q000528:radiation effects*; D008081:Liposomes / Q000737:chemistry / Q000528:radiation effects; D008863:Microspheres; D011100:Polyglycolic Acid / Q000737:chemistry* / Q000528:radiation effects*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry* / Q000528:radiation effects*; D013242:Sterilization / Q000379:methods*
chemical_list: D003692:Delayed-Action Preparations; D008081:Liposomes; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D007334:Insulin-Like Growth Factor I