THE ESTIMATION OF THE OXIDIZED AND REDUCED FORMS OF THE NICOTINAMIDE NUCLEOTIDES

Abstract

A method is described for the determination of the oxidized and reduced forms of the nicotinamide nucleotides by measuring the rate of the oxygen uptake with an oxygen electrode in a system in which the nucleotide acts as the rate-limiting carrier in cyclic system. The method permits the measurement of quantities as low as 0-02 [mu]g. of NAD+ or NADH or 0-01 [mu]g. of NADP+ or NADPH. The method permits the measurement of the nucteotides in extracts that contain non-specific reducing substances, coloured compounds or fluorescent materials, e.g. green leaves. The results obtained by the present method are compared with those reported in the literature.