Synthesis and characterizations of poly (ethylene glycol)-block-poly (glutamate) / 生物医学工程学杂志

ABSTRACT

Amine-terminated poly (ethylene glycol) (PEG) was prepared by two steps. Firstly, potassium naphthalene was added to a solution of methoxypolyethylene glycol 5,000 in benzene until the solution maintains green in half of an hour, then excess tosylchloride was introduced; secondly, the conversion of the tosylate into an amine was carried out by Gabriel synthesis. The block copolymer poly (ethylene glycol)-co-poly (gamma-benzyl L-glutamate ) could be obtained by ring-opening polymerization of gamma-benzyl-L-glutamate N-carboxy anhydride with amine-terminated PEG as macroinitiator. And the benzyl group could be removed by sodium hydroxide. The product structure was characterized by IR, 1HNMR, GPC. The cisplatin-loaded micelle was observed by transmission electron microscope (TEM). And the block copolymer is expected to be useful as functional materials including carrier systems in drug controlled delivery applications.