title: A pH-responsive chitosan-b-poly(p-dioxanone) nanocarrier: formation and efficient antitumor drug delivery.
abstract: Increasing attention has recently been paid to the fabrication of drug delivery systems with excellent cell internalization and intracellular drug release properties. In this study, an amphiphilic block copolymer of chitosan was synthesized for the first time, which can self-assemble into micelles in a neutral aqueous solution but partially disassemble in an acidic endosomal/lysosomal environment. The antitumor drug, camptothecin (CPT), was encapsulated in the cores of the micelles for tumor cell therapy. In vitro drug release studies demonstrated that the micelles presented a much faster release of CPT at pH 5.0 than at pH 7.4. Blank micelles were found to be nontoxic in preliminary in vitro cytotoxicity assays. Cell experiments showed that the CPT-loaded micelles could be effectively internalized by Hela cells and accomplished a potent antitumor cell efficacy, indicating that the chitosan-based micelles might be an attractive new platform for efficient intracellular drug delivery.
authors.affiliation: Center for Degradable and Flame-Retardant Polymeric Materials (ERCPM-MoE), College of Chemistry, State Key Laboratory of Polymer Materials Engineering, Sichuan University, 29 Wangjiang Road, Chengdu 610064, People's Republic of China.
authors.forename: Dao-Lu
authors.initials: DL
authors.lastname: Tang
authors.forename: Fei
authors.initials: F
authors.lastname: Song
authors.forename: Cheng
authors.initials: C
authors.lastname: Chen
authors.forename: Xiu-Li
authors.initials: XL
authors.lastname: Wang
authors.forename: Yu-Zhong
authors.initials: YZ
authors.lastname: Wang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000493:pharmacokinetics; D002166:Camptothecin / Q000008:administration & dosage / Q000493:pharmacokinetics; D002460:Cell Line; D048271:Chitosan / Q000031:analogs & derivatives / Q000737:chemistry; D004146:Dioxanes / Q000737:chemistry; D016503:Drug Delivery Systems; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D051379:Mice; D008823:Micelles; D053769:Nanocapsules / Q000008:administration & dosage* / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology; D011108:Polymers / Q000737:chemistry
chemical_list: D000970:Antineoplastic Agents; D000972:Antineoplastic Agents, Phytogenic; D004146:Dioxanes; D008823:Micelles; D053769:Nanocapsules; D011108:Polymers; C079733:poly-4-dioxan-2-one; D048271:Chitosan; D002166:Camptothecin