title: A convenient way to synthesize comb-shaped chitosan-graft-poly (N-isopropylacrylamide) copolymer.
abstract: Comb-shaped copolymers comprised of hydrophobic and hydrophilic blocks are self-assembled in aqueous solution, which results that they are suitable for delivery of hydrophobic drug molecules. Chitosan (CS) is an important biomaterial used widely in medical applications. Herein, a comb-shaped cationic copolymer composed of long biocompatible CS main chains and short PNIPAAm side chains was prepared via atom transfer radical polymerization (ATRP) by attaching an ATRP initiating group to N-phthaloyl chitosan. By subsequent removal of the protective groups on N-phthaloyl chitosan-graft-poly(N-isopropylacrylamide) (PHCS-g-PNIPAAm) copolymer with N(2)H(4)·H(2)O lead to the polymer pendant amino groups, this study attempted to synthesize a pH/temperature multi-responsive material. This chitosan-graft-poly(N-isopropylacrylamide) (CS-g-PNIPAAm) copolymer is self-assembled in aqueous solution into stimuli-responsive core-shell micelles with hydrodynamic diameters of about 170 nm. Structural organization and solution behavior were then investigated utilizing (1)H NMR spectroscopy, transmission electron microscopy (TEM) and dynamic light scattering (DLS).
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, and Department of Chemistry, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.forename: Mingzhu
authors.initials: M
authors.lastname: Liu
authors.forename: Chunmei
authors.initials: C
authors.lastname: Gao
authors.forename: Shaoyu
authors.initials: S
authors.lastname: Lü
authors.forename: Jiucun
authors.initials: J
authors.lastname: Chen
authors.forename: Xiyong
authors.initials: X
authors.lastname: Yu
authors.forename: Enyong
authors.initials: E
authors.lastname: Ding
authors.forename: Chuanming
authors.initials: C
authors.lastname: Yu
authors.forename: Jing
authors.initials: J
authors.lastname: Guo
authors.forename: Guijia
authors.initials: G
authors.lastname: Cui
mesh_terms: D000178:Acrylamides / Q000138:chemical synthesis / Q000737:chemistry; D000180:Acrylic Resins; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D009682:Magnetic Resonance Spectroscopy; D046529:Microscopy, Electron, Transmission; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry; D012996:Solutions / Q000737:chemistry; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D001672:Biocompatible Materials; D011108:Polymers; D012996:Solutions; D014867:Water; C052970:poly-N-isopropylacrylamide; D048271:Chitosan