DETERMINATION OF MALEIC HYDRAZIDE IN TOBACCO BY MICELLAR LIQUID-CHROMATOGRAPHY

A reversed-phase high-performance liquid chromatographic method with UV detection was C to determine maleic hydrazide (MH) residues in tobacco. Sample preparation consisted of an initial hydrolysis of MH residues with 12 M hydrochloric acid by sonication at an elevated temperature, followed by neutralization with an aqueous sodium hydroxide solution. Chromatographic separation was performed on a C18 column with a mobile phase containing 4.0 mM cetyltrimethylammonium bromide in 40 mM phosphate buffer (pH = 7.0). Other sample preparation procedures were investigated including extraction/digestion with the aid of different energy sources (c.g., conventional heater and microwave oven) and these results are also discussed.