An enantioselective fluorimetric assay for alcohol dehydrogenases using albumin-catalyzed beta-elimination of umbelliferone.

3-hydroxybutyl umbelliferyl ethers (R)-1 and (S)-1 are fluorogenic substrates for alcohol dehydrogenases. Their oxidation forms ketone 2, which undergoes beta-elimination of umbelliferone under catalysis by bovine serum albumin, leading to a > 20-fold fluorescence increase at lambda em = 460 +/- 20 nm (lambda ex = 360 +/- 20 nm). Enantioselectivity is determined in two separate tests with each enantiomeric substrate.