Differential pulse polarography as a tool for the determination of trace levels of nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+) in aqueous solution

Abstract

The differential pulse polarographic behavior of NAD + and NADP + has been investigated in phosphate buffer. The peaks obtained at pH 8.0 are recommended for the trace determination of these compounds. Linear calibration curves are obtained over the concentration ranges from 2.6 × 10 −7 to 2.6 × 10 −5 M for NAD + and from 2 × 10 −6 to 4 × 10 −5 for NADP +.