Abstract
A novel reversed-phase thin-layer chromatographic (RP-TLC) method was developed for simultaneous determination of ten most commonly used artificial food dyes. The method was validated with respect to specificity, linearity, precision, and accuracy and compared with reversed-phase high performance liquid chromatography (RP-HPLC) method. In the case of TLC method horizontal developing technique was employed using octadecyl-modified silica as a stationary phase and 0.5 mol dm−3 ammonium sulfate in 30% of ethanol-water solution as a mobile phase. HPLC analysis was carried out using XDB-C18 column and gradient of mixture of aqueous ammonium acetate solution (0.1 mol dm−3, pH = 6.5) and MeOH/ACN (1:1, v/v). Colorants were detected at 450, 500, and 625 nm wavelengths. The TLC method proved to be suitable for quantitative determination in relatively wide range of concentrations (20–300 ng/band). Satisfactory values of limits of detection and quantitation were established for both techniques, although somewhat higher in the case of TLC, ranging from 2–10 ng/band, that is, 3–20 ng/band. Both methods can be applied with satisfactory precision and accuracy, with clear advantage of TLC for simultaneous analysis of six samples per hour.
ACKNOWLEDGMENT
This work has been supported by the Ministry of Education, Science, and Technological Development of Serbia, grant No. 172017.
Notes
*L – Linear.
**P – Second order polynomial.
*Detected as 104b band.
**Detected as 132a band.
***Detected as 133a band.