Measurement of nicotinamide and N-methyl-2-pyridone-5-carboxamide in plasma by high performance liquid chromatography

We describe a simple and reproducible method for simultaneous determination of nicotinamide and its major human biological metabolite N-methyl-2-pyrid one-5-carboxamide (2pyr). Previous assays for nicotinamide in plasma and in urine have been complicated by the use of tedious extraction procedures or HPLC conditions which, although often allowing simultaneous analysis of se veral metabolites, add to the difficulties of performing multiple analyses. The procedure we describe is simple, using a rapid column clean-up of samp les prior to injection, which can then be done using an autosampler. Both n icotinamide and its major metabolite 2pyr can be assayed rapidly, with good reproducibility, and at the same time. Copyright (C) 1999 John Wiley & Son s, Ltd.