title: Biomimetic polymersomes as carriers for hydrophilic quantum dots.
abstract: For polymersomes to achieve their potential as effective delivery vehicles, they must efficiently encapsulate therapeutic agents into either the aqueous interior or the hydrophobic membrane. In this study, cell membrane-mimetic polymersomes were prepared from amphiphilic poly(D,L-lactide)-b-poly(2-methacryloyloxyethylphosphorylcholine) (PLA-b-PMPC) diblock copolymers and were used as encapsulation devices for water-soluble molecules. Thioalkylated zwitterionic phosphorylcholine protected quantum dots (PC@QDs) were chosen as hydrophilic model substrates and successfully encapsulated into the aqueous polymersome interior, as evidenced by transmission electron microscopy (TEM) and flow cytometry. In addition, we also found a fraction of the PC@QDs were bound to both the external and internal surfaces of the polymersome. This interesting immobilization might be due to the ion-pair interactions between the phosphorylcholine groups on the PC@QDs and polymersomes. The experimental encapsulation results support a mechanism of PLA-b-PMPC polymersome formation in which PLA-b-PMPC copolymer chains first form spherical micelles, then worm-like micelles, and finally disk-like micelles which close up to form polymersomes.
authors.affiliation: MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Gong-Yan
authors.initials: GY
authors.lastname: Liu
authors.forename: Xiang-Sheng
authors.initials: XS
authors.lastname: Liu
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Wang
authors.forename: Chao-Jian
authors.initials: CJ
authors.lastname: Chen
authors.forename: Jian
authors.initials: J
authors.lastname: Ji
mesh_terms: D032701:Biomimetics; D005434:Flow Cytometry; D046529:Microscopy, Electron, Transmission; D045663:Quantum Dots