title: Preparation and characterization of glutaraldehyde cross-linked O-carboxymethylchitosan microspheres for controlled delivery of pazufloxacin mesilate.
abstract: O-carboxymethylchitosan (OCMC) microspheres containing an antibiotic drug pazufloxacin mesilate (PM) have been successfully prepared by emulsion cross-linking using glutaraldehyde (GA). Various manufacturing parameters, including amount of cross-linking agent and OCMC:PM ratios were altered to optimize process variables during the microspheres production. The structure and morphology were characterized by Fourier transform infrared (FT-IR), wide-angle X-ray diffraction (WXRD) and scanning electron microscopy (SEM). The swelling and releasing behaviors of the microspheres at pH 1.2 and 7.4 media were investigated. The results revealed that the microspheres had a spherical, rough morphology and with a narrow size distribution. The degree of swelling of microspheres at pH 7.4 media was higher than that at pH 1.2 media. The microspheres proved to be successful in prolonging drug release. The release of PM was found to depend upon the extent of matrix cross-linking and drug loading. The release profiles of PM from OCMC microspheres were found to be biphasic with a burst release followed by a gradual release phase, and followed the Higuchi matrix model.
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Yan-Fei
authors.initials: YF
authors.lastname: Liu
authors.forename: Ke-Long
authors.initials: KL
authors.lastname: Huang
authors.forename: Dong-Ming
authors.initials: DM
authors.lastname: Peng
authors.forename: Ping
authors.initials: P
authors.lastname: Ding
authors.forename: Gui-Yin
authors.initials: GY
authors.lastname: Li
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry; D003432:Cross-Linking Reagents; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems; D024841:Fluoroquinolones / Q000008:administration & dosage* / Q000737:chemistry; D005976:Glutaral; D066298:In Vitro Techniques; D046911:Macromolecular Substances / Q000138:chemical synthesis / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010078:Oxazines / Q000008:administration & dosage* / Q000737:chemistry; D010316:Particle Size; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D003692:Delayed-Action Preparations; D024841:Fluoroquinolones; D046911:Macromolecular Substances; C504164:O-carboxymethylchitosan; D010078:Oxazines; D011108:Polymers; C078052:pazufloxacin; D048271:Chitosan; D005976:Glutaral