General Description
EGS is a water-insoluble, homobifunctional N-hydroxysuccinimide ester (NHS ester) and Sulfo-EGS is its water-soluble analog. The spacer arm contains two cleavable ester sites that may be broken with hydroxylamine, which yields two fragments with terminal amide bonds and the release of ethylene glycol. These reagents are often used for conjugating radiolabeled ligands to cell surface receptors. The water insoluble reagent EGS does not possess a charged group, is lipophilic and, therefore, membrane-permeable and useful for intracellular and intramembrane protein conjugation. EGS is first dissolved in DMSO or DMF and added to the aqueous reaction mixture at a final solvent concentration of 10-20%, to minimize detrimental affects to the protein.
