Abstract: A method of assay for the presence of .alpha.-amylase in a sample employs a derivatized .alpha.-oligosaccharide which can be hydrolyzed by an enzyme mix including .alpha.-amylase to yield an electroactive compound, and at least one other enzyme which with .alpha.-amylase gives an enzyme mix capable of hydrolyzing the derivatized .alpha.-oligosaccharide. The sample is contacted with the derivatized .alpha.-oligosaccharide and with the other enzyme to permit hydrolysis of the derivatized .alpha.-oligosaccharide and to allow formation of the electroactive compound. An electrode is poised at a potential at which the derivatized .alpha.-oligosaccharide is not electochemically active, the potential being one at which the electroactive compound is electochemically active. Any current arising from electrochemical activity of the electroactive compound is detected.