title: Preparation of chitosan microspheres by ionotropic gelation under a high voltage electrostatic field for protein delivery.
abstract: Biodegradable microspheres have been widely used in drug/protein delivery system. In this paper, a modified ionotropic gelation method combined with a high voltage electrostatic field was developed to prepare protein-loaded chitosan microspheres. Bovine serum albumin (BSA) was chosen as a model protein. The preparation process and major parameters were discussed and optimized. The morphology, particle size, encapsulation efficiency and in vitro release behavior of the prepared microspheres were investigated. The results revealed that the microspheres exhibited good sphericity and dispersity when the mixture of sodium tripolyphosphate (TPP) and ethanol was applied as coagulation solution. Higher encapsulation efficiency (>90%) was achieved for the weight ratio of BSA to chitosan below 5%. 35% of BSA was released from the microspheres cured in 3% coagulation solution, and more than 50% of BSA was released from the microspheres cured in 1% coagulation solution at pH 8.8. However, only 15% of BSA was released from the microspheres cured in 1% coagulation solution at pH 4. The results suggested that ionotropic gelation method combined with a high voltage electrostatic field will be an effective method for fabricating chitosan microspheres for sustained delivery of protein.
authors.affiliation: Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Key Laboratory of Advanced Polymeric Materials, and Engineering Research Center for Biomedical Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Ma
authors.forename: Changsheng
authors.initials: C
authors.lastname: Liu
mesh_terms: D000818:Animals; D002417:Cattle; D048271:Chitosan / Q000138:chemical synthesis* / Q000494:pharmacology; D016503:Drug Delivery Systems / Q000379:methods*; D000431:Ethanol; D005782:Gels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012996:Solutions; D055672:Static Electricity
chemical_list: D005782:Gels; D012996:Solutions; D012710:Serum Albumin, Bovine; D000431:Ethanol; D048271:Chitosan