Abstract
A simple and precise RP-HPLC method has been developed and validated for the separation and trace determination of selected food colorant residues, namely, Tartrazine (E102), Sunset Yellow (E110) and Allura Red (E129), in water samples. The colorants were separated in less than five minutes using buffered distilled water as a mobile phase on a superheated hybrid ODS X-Bridge RP-C18 column (150 x 3.5 mu m, 4.6 mm i.d.). Van't Hoff plots were linear for all the tested colorants at different mobile phases and without any significant changes in their retention factors or the transition stage of the stationary phase. The lower limits of detection for E102 and E110 were found to be 0.5 and 0.016 mg/mL, respectively, whereas for E129 it was 0.0004 mg/mL. The proposed method was checked for its accuracy and precision and was applied to determine the selected colorants in soft drinks and environmental water samples with acceptable recoveries in the range from 83.5 +/- 1.9 to 114 +/- 3%.