Cholesterol-PEG-Vinylsulfone, MW 5,000 can react with thiol-containing molecule in the presence of photoinitiator via thiol-ene reaction. It is an amphipilic polymer which can self-assemble and encapsulate hydrophobic drugs in an aqueous solution. The polymer is commonly used for preparation of liposome in controlled drug delivery applications. Reagent grade, for research purpose.