title: Evaluation of process parameters involved in chitosan microsphere preparation by the o/w/o multiple emulsion method.
abstract: Chitosans are interesting biopolymers largely studied for applications in the medical and pharmaceutical fields. In this work, an o/w/o multiple emulsion technique was used for the preparation of hydrophobic drug loaded microspheres. Moreover, the influence of critical variables (concentration of acetic acid in the polymer solution and drug-polymer ratio) on microsphere morphology and drug content was evaluated. Two chitosans of different molecular weights and deacetylation degree were employed; ketoprofen, a non-steroidal anti- inflammatory drug, was chosen as the hydrophobic model drug. The multiple emulsion method produced well-formed microspheres with good yields. Acetic acid concentration in the polymeric solutions influenced particle size and drug content of the microspheres. The highest drug encapsulation efficiencies were obtained for the lowest theoretical drug/chitosan ratio.
authors.affiliation: Department of Pharmaceutical Chemistry, University of Pavia, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Pavanetto
authors.forename: P
authors.initials: P
authors.lastname: Perugini
authors.forename: B
authors.initials: B
authors.lastname: Conti
authors.forename: T
authors.initials: T
authors.lastname: Modena
authors.forename: I
authors.initials: I
authors.lastname: Genta
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D002686:Chitin / Q000031:analogs & derivatives* / Q000737:chemistry; D048271:Chitosan; D004655:Emulsions / Q000737:chemistry; D005069:Evaluation Studies as Topic; D007660:Ketoprofen / Q000008:administration & dosage / Q000737:chemistry; D008863:Microspheres; D008970:Molecular Weight; D010316:Particle Size
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D001672:Biocompatible Materials; D004655:Emulsions; D002686:Chitin; D048271:Chitosan; D007660:Ketoprofen