A liquid chromatography tandem mass spectrometry method using positiveelectrospray ionization source (ESI+), multiple reaction monitoring (MRM) mode has been developed and validated to simultaneously determine 16 illegaldyes in different food groups. The method was based on the extraction of analytes from samples using QuEChERS technique. After being cleaned up d-SPE tube with mixture of MgSO4, PSA and C18 sorbent, the extract was analyzed by LC-MS/MS. Each illegaldyewas characterized by a precursor ion and two product ions. The method allows the screening of the simultaneous presence of 16 illegal substances at the lowest concentration of 5µg/kg forrhodamin B, crystal violet, chrysoidine G, auramine O, sudan black B, pararosanilin and of 50µg/kg for remaining substances. The specificity of the methodmet 657/2002/EC requirements. The methodwas linear in the range from 1-1000µg/L and themethod detection limit was from 5-50 µg/kg, the recovery ranged from 73-104% and the relative standard deviations were lower than 16.4%. The method has been applied to analyze 30 samples of dried beef, dry chicken, chutney, chili powder and food coloring samples. Rhodamine B, sudan I and auramine O were detected in two chili powder and 04 food coloring samples.
LC-MS/MS, illegal dyes, foodstuffs, dried beef, dried chicken, food colour
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