title: Self-assembly of pH-sensitive mixed micelles based on linear and star copolymers for drug delivery.
abstract: Comicellization of a star block copolymer poly(ε-caprolactone)-block-poly(diethylamino)ethyl methacrylate (S(PCL-b-PDEAEMA)) and a linear block copolymer methoxy poly(ethylene glycol)-block-poly(ε-caprolactone) (mPEG-b-PCL) was developed to enhance the stability and lower the cytotoxicity of the micelles. The two copolymers self-assembled into the mixed micelles with a common PCL core surrounded by a mixed PDEAEMA/mPEG shell in aqueous solution. This core-shell structure was transformed to the core-shell-corona structure at high pH due to the collapse of the PDEAEMA segment. The properties of the polymeric micelles were greatly dependent on the weight ratio of the two copolymers and the external pH. As increasing the mPEG-b-PCL content, the size and the zeta potential of the mixed micelles were lowered while the pH-dependent stability and the biocompatibility were improved. Moreover, an increase in pH accelerated the release of indomethacin (IND) from the mixed micelles in vitro. These results augured that the mixed micelles could be applied as a stable pH-sensitive release system.
authors: Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
authors: Xiujuan
authors: X
authors: Huang
authors: Yan
authors: Y
authors: Xiao
authors: Meidong
authors: M
authors: Lang
mesh_terms: D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D016503:Drug Delivery Systems; D006863:Hydrogen-Ion Concentration; D059630:Mesenchymal Stem Cells / Q000187:drug effects; D008823:Micelles; D015394:Molecular Structure; D010316:Particle Size; D011108:Polymers / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology; D013329:Structure-Activity Relationship; D013499:Surface Properties
chemical_list: D008823:Micelles; D011108:Polymers