Optimization of conditions for the HPLC determination of synthetic dyes in food

The retention of synthetic food dyes on the sorbent Kromasil C 18 was studied under the conditions of reversed-phase and ion-pair high-performance liquid chromatocoraphy, depending on the concentrations of the ion-pair reagent (tetrabutylammonium dihydrophosphate) and organic solvent (acetonitrile) in the mobile phase and on the concentration and pH of the phosphate buffer solution. The optimum conditions were selected for the separation of ten dyes in the isocratic elution mode within 25 min. A procedure was developed for the determination of synthetic food dyes in foodstuffs; the detection limit was 10-30 muL.