Abstract: A method for the determination of 27 industrial dyes in juice and wine has been developed using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Acetonitrile was used as extraction solvent, and sodium chloride was added to salt out the analytes from the samples. Chromatographic separation was performed on a C18 column with the gradient elution and the mass spectrometric acquisition was carried out under the mode of multiple reaction monitoring (MRM). Twenty-four of the 27 dyes were detected under positive ionization mode using the mobile phase of acetonitrile and water containing 0.1% formic acid. The other 3 dyes were analyzed under negative ionization mode with the mobile phase of acetonitrile and water. As a result, the average recoveries of 27 dyes spiked in juice ranged from 57.0% to 117.7% with the relative standard deviations (RSDs) of 2.4%~17.7%, and the average recoveries of 27 dyes spiked in wine ranged from 40.8% to 109.4% with the RSDs of 1.6%~17.9%. The limits of quantification (LOQs) of 27 dyes spiked in juice were in the range of 0.1~50 μg/kg, and 0.2~50 μg/kg for those spiked in wine. This method can be applied to rapid detection of illegally added dyes in soft drinks due to its simplicity and high sensitivity.

Key words: industrial dyes, juice, wine , ultra performance liquid chromatography-electrospray ionization tandem quadrupole mass spectrometry (UPLC-ESI-MS/MS)