Premium
Poly( N ‐isopropylacrylamide‐ co ‐hydroxyethyl methacrylate) graft copolymers and their application as carriers for drug delivery system
Author(s) -
Quynh Tran Minh,
Yoneyamab Masaru,
Maki Yasuyuki,
Dobashi Toshiaki
Publication year - 2011
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.34821
Subject(s) - lower critical solution temperature , copolymer , polymer chemistry , methacrylate , materials science , poly(n isopropylacrylamide) , polymerization , micelle , 2 hydroxyethyl methacrylate , dynamic light scattering , grafting , amphiphile , drug carrier , chemical engineering , drug delivery , nanoparticle , chemistry , aqueous solution , polymer , organic chemistry , nanotechnology , composite material , engineering
Poly( N ‐isopropylacrylamide‐ co ‐hydroxyethyl methacrylate) [P(NIPAM‐ co ‐HEMA)] copolymer was synthesized by controlled radical polymerization from respective N ‐isopropylacrylamide (NIPAM) and hydroxyethyl methacrylate (HEMA) monomers with a predetermined ratio. To prepare the thermosensitive and biodegradable nanoparticles, new thermosensitive graft copolymer, poly( L ‐lactide)‐ graft ‐poly( N ‐isoporylacrylamide‐ co ‐hydroxyethyl methacrylate) [PLLA‐ g ‐P(NIPAM‐ co ‐HEMA)], with the lower critical solution temperature (LCST) near the normal body temperature, was synthesized by ring opening polymerization of L ‐lactide in the presence of P(NIPAM‐ co ‐HEMA). The amphiphilic property of the graft copolymers was formed by the grafting of the PLLA hydrophobic chains onto the PNIPAM based hydrophilic backbone. Therefore, the graft copolymers can self‐assemble into uniformly spherical micelles ò about 150–240 nm in diameter as observed by the field emission scanning electron microscope and dynamic light scattering. Dexamethasone can be loaded into these nanostructures during dialysis with a relative high loading capacity and its in vitro release depends on temperature. Above the LCST, most of the drugs were released from the drug‐loaded micelles, whereas a large amount of drugs still remains in the micelles after 48 h below the LCST. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012