Chemical agents used to modify the amino acid side chains of proteins in order to alter their native charges, block or expose reactive binding sites, inactivate functional groups, and change functional groups to create targets for crosslinking and labeling.
2-Iminothiolane-HCl (CAS 4781-83-3); an amine-reactive thiolation reagent to cap protein primary amines with sulfhydryl groups for immediate crosslinking.
A three-branched, polyethylene glycol compound (3 times 12 PEG units) activated as an NHS ester for covalent PEGylation of primary amines on proteins or assay surfaces.