The separation and determination of quinine in bitter drinks by micellar electrokinetic capillary chromatography.

: A rapid method for the determination of quinine in bitter drinks by micellar electrokinetic capillary chromatography (MECC) with ultraviolet (UV) detection is described. The beverage is simply diluted with deionized water, filtered, and analyzed using a 75 cm x 75 micrometer uncoated fused-silica capillary column with a buffer consisting of 15% methanol and 85% of a mixture of 0.05 M cetyltrimethylammonium bromide (CTAB), 0.01 M sodium tetraborate, and 0.01 M potassium dihydrogen orthophosphate, pH 8.6, with an operating voltage of -25 kV. The levels of quinine determined by MECC were in good agreement with those determined by HPLC. The CVs for area calculation (2.1%, n = 7) and migration time variation (1.3%, n = 20) for multiple injections of a sample solution by MECC were satisfactory.