6-Azidohexanoic Acid STP Ester

6-Azidohexanoic Acid STP Ester is an amine-reactive, water-soluble labeling reagent used to modify proteins, antibodies, and other amine-containing biopolymers in aqueous media. 6-Azidohexanoic Acid STP Ester undergoes hydrolysis in aqueous media at much slower rate compared to compared to 6-Azidohexanoic Acid Sulfo-NHS Ester allowing for more efficient labeling of biomolecules in aqueous media.

4-Sulfo-2,3,5,6-tetrafluorophenyl (STP) esters is another type of carboxylic acid derivative that react with primary amines forming covalent amide bond. The amine linkage bond is identical to one formed by the reaction between primary amines and NHS esters or sulfo-NHS esters. However, in most cases, STP ester displays much better stability toward hydrolysis in aqueous media resulting in more efficiency and better reproducible labeling of biopolymers.

6-Azidohexanoic Acid STP Ester is a reagent of choice for applications that cannot tolerate organic co-solvents or are complicated by their inclusion. Specific labeling of cell surface proteins is another common application for these uniquely water-soluble and membrane impermeable reagents. A short spacer arm adds minimal mass to modified molecules (84.1 daltons).