FLUOROMETRIC ASSAY OF NIACINAMIDE IN VITAMIN PREPARATIONS : (I) BASIC STUDIES ON THE FLUOROMETRY OF NIACINAMIDE

Abstract

For chemical determination of niacinamide in multivitamin preparations, a modified Scudi's method of fluorometry was used. From the results of numerous experiments with pure niacinamide the following procedures were found to be suitable for routine work. One ml of BrCN was pipetted into 2 ml of niacinamide solution which was dissolved in phosphate buffer(pH 7), the solution was kept at 80℃ for 7 minutes and 7ml of 0.75 N NaOH was added to it. After allowing to stand for one hour, the intensity of the fluorescence was measured. The optimal range of concentration for this method was 0.1〜1.0 μg/ml. The formation of fluorescent substance was also studied by measuring changes of the ultraviolet absorption spectra at each step of the reaction.