title: Diblock copolymers of polyethylene glycol and a polymethacrylamide with side-chains containing twin ortho ester rings: synthesis, characterization, and evaluation as potential pH-responsive micelles.
abstract: The diblock copolymer, PEG-b-PMEA, was synthesized by reversible-addition fragmentation chain transfer polymerization (RAFT). The PMEA block contained a polymethacrylamide backbone and twin ortho ester rings in the side-chains. At neutral pH, PEG-b-PMEA self-assembled to form stable micelles. At pH 5, the twin ortho ester rings were quickly hydrolyzed to completion in 12 h, and releasing nearly 70% of the encapsulated Nile Red dye. The PEG-b-PMEA micelles were completely nontoxic to cultured cells as determined by the MTT assay. Paclitaxel (PTX)-loaded micelles showed toxicity toward lung cancer cells comparable to that of the free PTX at equivalent doses. These results suggest that the PEG-b-PMEA micelles could be useful nano-carriers for pH-responsive delivery of poorly soluble anticancer drugs.
authors.affiliation: School of Pharmaceutical Science, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu Province, 214122, P. R. China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Zhou
authors.forename: Shi
authors.initials: S
authors.lastname: Luo
authors.forename: Rupei
authors.initials: R
authors.lastname: Tang
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
mesh_terms: D000178:Acrylamides / Q000138:chemical synthesis* / Q000737:chemistry; D000818:Animals; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D016923:Cell Death / Q000187:drug effects; D004952:Esters / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D051379:Mice; D008823:Micelles; D041681:NIH 3T3 Cells; D010078:Oxazines; D010316:Particle Size; D011092:Polyethylene Glycols / Q000138:chemical synthesis* / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D066244:Proton Magnetic Resonance Spectroscopy
chemical_list: D000178:Acrylamides; D004952:Esters; D008823:Micelles; D010078:Oxazines; D011109:Polymethacrylic Acids; D011092:Polyethylene Glycols; C045985:methacrylamide; C044808:nile red
keywords: acid-labile; drug delivery; micelles; ortho ester