Bromoacetamido-PEG2-NHS ester is a PEG linker containing a bromide group and an NHS ester. The hydrophilic PEG spacer increases solubility in aqueous media. The bromide (Br) is a very good leaving group for nucleophilic substitution reactions. The NHS ester can be used to label the primary amines (-NH2) of proteins, amine-modified oligonucleotides, and other amine-containing molecules.
