Simple and rapid method for determining nicotinamide adenine dinucleotide synthetase activity by high-performance liquid chromatography

A method is described for the determination of nicotinamide adenine dinucleotide synthetase (NADS) activity in human blood. Using high-performance liquid chromatography (HPLC), the formed NAD is separated from the substrates and the other blood components in less than 13 min. The activity of NADS determined by HPLC is closely correlated with that determined by the conventional spectrophotometric method, which requires two steps of enzyme reaction. The present method is simple and reliable and facilitates the routine analysis of NADS activity.