Study on the Combination of Multi-wavelength Calibration and Liquid Chromatography with UV–Vis Detector for the Determination of the Synthetic Dye Sunset Yellow FCF in Soft Drinks

Calibration is a fundamental step in instrumental quantitative methods that produce an analytical signal proportional to the concentration of the analyte in the sample. Multi-wavelength calibration (MWC), a novel calibration strategy, has been proposed as a simple method for the determination of analytes in samples with complex matrices. It has minimal matrix effects and straightforward sample preparation. The objective of this work was to apply this calibration strategy to the determination of the synthetic dye Sunset Yellow in soft drinks by high-performance liquid chromatography with ultraviolet–visible analysis (HPLC/UV–Vis). Multi-wavelength calibration planning was performed as recommended in the literature. MWC results were statistically compared with conventional external calibration (limit of detection, limit of quantification, linearity, repeatability and recovery). The results obtained with both calibrations showed that the soft drinks complied with Brazilian legislation. The dye contents obtained with both calibration methods did not show significant statistical differences. MWC appears as an alternative or complement to external calibrations and ensures minimal matrix effects and straightforward sample preparation.