title: Layer-by-layer assembly of poly(L-glutamic acid)/chitosan microcapsules for high loading and sustained release of 5-fluorouracil.
abstract: Hollow polyelectrolyte microcapsules based on poly(l-glutamic acid) (PLGA) and chitosan (CS) with opposite charges were fabricated by layer-by-layer (LbL) assembly technique using melamine formaldehyde (MF) microparticles as sacrificial templates. The LbL assembly of polyelectrolytes and the resultant PLGA/CS microcapsules were characterized. A hydrophilic anticancer drug, 5-fluorouracil (5-FU), was chosen to investigate the loading and release properties of the microcapsules. The PLGA/CS microcapsules show high loading capacity of 5-FU under conditions of high drug concentration and salt adding. The high loading can be ascribed to spontaneous deposition of 5-FU induced by hydrogen bonding between 5-FU and PLGA/CS microcapsules. The PLGA/CS microcapsules show sustained release behavior. The release rate of 5-FU drastically slows down after loading in PLGA/CS microcapsules. The 5-FU release from PLGA/CS microcapsules can be best described using Ritger-Peppas or Baker-Londale models, indicating the diffusion mechanism of 5-FU release from the PLGA/CS microcapsules. In vitro cytotoxicity evaluation by the MTT assay shows good cell viability over the entire concentration range of PLGA/CS microcapsules. Therefore, the novel PLGA/CS microcapsules are expected to find application in drug delivery systems because of the properties of biodegradability, high loading, sustained release and cell compatibility.
authors.affiliation: Department of Polymer Materials, Shanghai University, Shanghai, China.
authors.forename: Shifeng
authors.initials: S
authors.lastname: Yan
authors.forename: Jie
authors.initials: J
authors.lastname: Zhu
authors.forename: Zhichun
authors.initials: Z
authors.lastname: Wang
authors.forename: Jingbo
authors.initials: J
authors.lastname: Yin
authors.forename: Yanzhen
authors.initials: Y
authors.lastname: Zheng
authors.forename: Xuesi
authors.initials: X
authors.lastname: Chen
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000737:chemistry*; D002214:Capsules / Q000737:chemistry* / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000737:chemistry; D003692:Delayed-Action Preparations / Q000737:chemistry; D004337:Drug Carriers / Q000737:chemistry* / Q000633:toxicity; D004339:Drug Compounding / Q000379:methods; D016503:Drug Delivery Systems; D005079:Excipients / Q000737:chemistry; D005347:Fibroblasts; D005472:Fluorouracil / Q000737:chemistry*; D018698:Glutamic Acid / Q000737:chemistry; D051379:Mice; D010599:Pharmacokinetics; D012995:Solubility
chemical_list: D000964:Antimetabolites, Antineoplastic; D002214:Capsules; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D005079:Excipients; D018698:Glutamic Acid; D048271:Chitosan; D005472:Fluorouracil