Thin layer chromatographic identification and quantitation of niacin and niacinamide in pharmaceutical preparations.

A safe and simple thin layer chromatographic method has been developed for the estimation of niacin and niacinamide in pharmaceutical preparations containing other vitamins, enzymes, herbs, antiamoebic drugs, etc. The method involves removal of excipients from the preparation by ethanol precipitation and isolation of niacin or niacinamide from other ingredients by TLC on silica gel with water as developing solvent, followed by extraction in 0.1N HCl, and spectrophotometric estimation of the vitamin at 262 nm. The percent recoveries for niacin and niacinamide were 100.1 +/- 1.9 and 100.2 +/- 1.5, respectively.