4arm-PEG-VA

4 arm-Polyethylene glycol-Valeric Acids, 4 arm-PEG-VA, VA-PEG- 4 arm from ruixi 4-arm polyethylene glycol- VA is a multi-arm polyethylene glycol derivative with VA  at each end of the four arms connected to a pentaerythritol nucleus.4 arm-peg2000-VA,4 arm-peg5000-VA and so on.The valeric acid carboxylate of d-biotin may be activated to an NHS ester for direct modification of amine groups in proteins and other molecules. NHS esters react by nucleophilic attack of an amine on the carbonyl group, releasing the NHS group and forming a stable amide linkage.

msds of 4 arm-PEG-VA