Specificity is imparted to the NAD/NADH-Glo™ and NADP/NADPH-Glo™ Assay reactions by including NAD or NADP Cycling Enzyme and NAD or NADP Cycling Substrate to selectively measure nonphosphorylated and phosphorylated nucleotides, respectively. Accessory protocols are provided to allow separate measurements of NAD+ and NADH or NADP+ and NADPH and calculation of the ratio of the oxidized and reduced forms.
NADH, NADPH, NAD+ and NADP+ were prepared and diluted to the indicated concentrations in phosphate-buffered saline.