title: Different molecular weight chitosan microspheres: influence on drug loading and drug release.
abstract: Influence of chitosan molecular weight on drug loading and drug release of drug-loaded chitosan microspheres was studied. Chitosans of 70,000 (LC), 750,000 (MC), and 2,000,000 (HC) molecular weight were employed alone or as mixtures (HC/LC 1:1-1:2 w/w). Ketoprofen (ket) was chosen as the model drug to be encapsulated. Microspheres characterized by different theoretical polymer/drug ratios were prepared (2:1, 1:1, 1:2 w/w). Satisfactory ket contents were obtained for all batches of chitosan microspheres with the theoretical polymer/drug ratio 1:2 w/w; microspheres made of HC/LC (1:2 w/w) were characterized by good drug content and encapsulation efficiency independent by polymer/drug ratio. Prepared chitosan microparticulate delivery systems can modulate ket release within 48 hr. Microspheres consisting of HC/LC (1:2 w/w) were the most suitable formulation in controlling drug release.
authors.affiliation: Department of Pharmaceutical Chemistry, University of Pavia, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Genta
authors.forename: P
authors.initials: P
authors.lastname: Perugini
authors.forename: F
authors.initials: F
authors.lastname: Pavanetto
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D001672:Biocompatible Materials / Q000737:chemistry*; D002686:Chitin / Q000031:analogs & derivatives* / Q000737:chemistry; D048271:Chitosan; D004339:Drug Compounding; D016503:Drug Delivery Systems; D007660:Ketoprofen / Q000008:administration & dosage*; D008863:Microspheres; D008970:Molecular Weight; D014783:Viscosity
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D001672:Biocompatible Materials; D002686:Chitin; D048271:Chitosan; D007660:Ketoprofen