PCL(3k)-PEG(3k)-Thiol is widely used amphiphilic polymer to prepare drug loaded nanoparticles for drug delivery or scaffold in tissue engineering. It is an amphiphilic block polymer with a PEG hydrophilic attached to a hydrophobic polycaprolactone (PCL) block. The thiol moiety is reactive with maleimide via thioether bond formation. Reagent grade, for research purpose.