title: In vitro evaluation of gentamicin released from microparticles.
abstract: In this study, the preparation, characterization and drug release behaviour of gentamicin (GM)-loaded poly(D,L-lactide-co-glycolide) microspheres are described. The microspheres were produced using a double emulsion solvent evaporation technique. All the microspheres preparation resulted in spherical shape and the mean diameter was 3 microm (for empty microspheres) and between 5 and 9 microm for microparticles loaded with GM. The encapsulation efficiency (EE) ranged from 3.4 to 90% depending on the formulation. Increasing the volume of the external aqueous phase, increased the EE. Encapsulation also depended on the pH value of the internal aqueous phase, the highest value was achieved when maintained the internal aqueous phase at pH 6, where GM was more soluble. Moreover, increasing nominal GM loading yielded lower encapsulation efficiencies. The release profiles of GM from microparticles resulted in biphasic patterns. After an initial burst, a continuous drug release was observed for up to 4 weeks. Finally, the formulations with higher loading released the drug faster.
authors.affiliation: Department of Pharmacy and Pharmaceutical Technology, University of Navarra, 31080, Pamplona, Spain. mjblanco@unav.es
authors.forename: M J
authors.initials: MJ
authors.lastname: Blanco-Príeto
authors.forename: C
authors.initials: C
authors.lastname: Lecaroz
authors.forename: M J
authors.initials: MJ
authors.lastname: Renedo
authors.forename: J
authors.initials: J
authors.lastname: Kunkova
authors.forename: C
authors.initials: C
authors.lastname: Gamazo
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry; D004337:Drug Carriers; D004339:Drug Compounding / Q000379:methods; D005839:Gentamicins / Q000008:administration & dosage* / Q000737:chemistry; D007700:Kinetics; D019344:Lactic Acid; D008863:Microspheres; D010316:Particle Size; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D012997:Solvents
chemical_list: D000900:Anti-Bacterial Agents; D004337:Drug Carriers; D005839:Gentamicins; D011108:Polymers; D012997:Solvents; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid