PLGA(4k)-PEG(5k)-COOH is a carboxyl terminated amphiphilic polymer which can react with amine (NH2) in the presence of HATU or EDC. In water, the polymer self assembles to form micelles with poly(lactide-co-glycolide) (PLGA) core being shielded from the water by PEG shell. The polymer can be used to prepare drug loaded nanoparticles for drug delivery. Reagent grade, for research purpose.