In biochemistry, 2,2`-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) or ABTS is chemical compound used to observe the reaction kinetics of specific enzymes. A common use for it is in the enzyme-linked immunosorbent assay (ELISA) to detect for binding of molecules to each other. ... Found on http://en.wikipedia.org/wiki/ABTS