Bioluminescent assay of D-3-hydroxybutyrate in serum.

An enzymatic assay of D-3-hydroxybutyrate in which the hydroxybutyrate dehydrogenase reaction is coupled to the bacterial oxidoreductase-luciferase system is described. The bioluminescent assay is based on either, end-point, or on initial velocity measurements. This simple and rapid assay requires a single serum sample of 10 microliters. Its linear range covers two orders of magnitude from 10(-6) mol/l upwards. This assay is suitable for the routine determination of D-3-hydroxybutyrate in human blood with good accuracy.