A Liquid Chromatography Procedure for Analysis of Nicotine on Cellulose Acetate Filters

A procedure has been developed for filter analysis whereby the cellulose acetate is dissolved in acetonitrile to release any trapped nicotine. Dissolving the filter eliminates time consuming steam distillation or solvent extraction steps and assures that the recovery of nicotine is complete. After the filter is dissolved, the cellulose acetate is precipitated by addition of an amine-phosphate buffer and an aliquot of the filtered solution is analysed by high-pressure liquid chromatography (HPLC). Two methods of HPLC analysis are described. In both cases the separation is achieved on a cyano-bonded silica column and detection is by ultra-violet absorption at 254 nm. Different mobile phases are used in the two methods. In the first procedure, a diethylamine-phosphate buffer at pH 7.56 is used while in the second procedure, a dimethylamine-phosphate buffer at pH 3.00 is used. Analytical results are equivalent for both chromatographic methods, but the second procedure may offer extended analytical column life. Results of a study relating the structure of the amine in the mobile phase to nicotine retention are presented. The amount of nicotine trapped on cellulose acetate filters during smoking was determined with increasing intervals between smoking and analysis. These results demonstrate that nicotine is stable on filters and previous problems of analysis were caused by difficulty in removal from aged filters.