The Determination of Nicotine in Particulate Matter Using Citric Acid and Bromomaleic Acid

It was found that a system consisting of citric acid and bromomaleic acid each dissolved in acetic anhydride may be used to quantitatively determine nicotine, colourimetrically, in a 2-propanoI extract of smoke particulate matter. The coloured complex between nicotine and the above reagents formed in 25 minutes (at 30°C) and had a l_max at 505 nanometers. With nicotine, complexation occurred preferentially at the N-methylpyrrolidine nitrogen as opposed to the pyridine nitrogen. Out of the classes of compounds that were tested, which included primary, secondary and aliphatic and aromatic amines, oximes and amides, only tertiary aliphatic amines yielded a red coloured complex. The coefficient of variation at the 2-sigma level was 11 %.