Determination of ten basic dyes in meat products by ultra fast liquid chromatography-ion trap time of flight mass spectrometry

A method was developed for the simultaneous determination of 10 basic dyes in meat products using ultra fast liquid chromatography-ion trap time of flight mass spectrometry (LC-IT-TOF-MS). The target analytes were separated at a flow rate of 0.2 mL/min on a Waters Acquity UPLC BEH C18 (100 mm x 2.1 mm, 1.7 microm) column with a gradient elution. The mobile phase was 5 mmol/L ammonium acetate-acetonitrile (containing 0.1% (v/v) formic acid). The identification and quantification were achieved in positive ion mode with electro spray ionization source. The samples were extracted with a simple procedure using acetonitrile and cleaned up by weak cation exchange (Oasis WCX) solid phase extraction column. Ten basic dyes were determined by LC-IT-TOF-MS, and quantified by external standard method. The developed method showed a good linearity over the wide range of 1.0 - 100.0 microg/L, and the relative standard deviations (n = 7) were less than 8.54%. The average recoveries of the ten basic dyes at three levels (2, 10 and 25 microg/kg) were ranged from 65.39% to 119.18%. Therefore, this method, owing to its simplicity, rapidity and high sensitivity, has a good applicability to the simultaneous determination of dye residues in meat products.