Abstract
Fast and simple capillary electrophoresis method was proposed for the simultaneous determination of caffeine, vanillin, and ethyl vanillin in beverages. The optimal separation conditions were 25 mM phosphate buffer at pH 8.5, containing 10% (v/v) acetonitrile and UV‐absorption detection at the wavelength of 200 nm. Employing the optimum conditions, the three compounds were separated in less than 3 min. The procedure was validated with respect to linearity, limits of detection, limits of quantitation, (RSD%) accuracy (recovery), and precision (repeatability). Calibration curves with (r2 > 0.9986) in the concentration range of 5–80 μg/mL were obtained for the three analytes. The limits of detection and quantitation in the range of 2.6‐4.3 and 4.1‐5.2 μg/mL were obtained, respectively. Recoveries of analytes in range from 92.1 to 104.4%, (n = 3) were attained. The validated method was successfully utilized for the analysis of the analytes in beverage samples.