Biotin-PEG*-NHS Ester reacts specifically and efficiently with
primary amines (e.g., a side chain of lysine residues or
aminosilane-coated surfaces) at pH **9 to form covalent bonds. The
hydrophilic polyethylene glycol (PEG) spacer arm of this reagent
imparts water solubility that is transferred to the labeled
molecule, thus reducing aggregation of labeled proteins stored in
solution. The PEG spacer arm also gives the reagent a long and
flexible connection to minimize steric hindrance involved with
binding to avidin molecules.
