HPLC-q/LIT-MS Determination of Malachite Green, Crystal Violet and their Metabolites in Aquatic Products and Feed

A method of HPLC-q/LIT-MS for the determination of malachite green, crystal violet and their metabolites (leucomalachite green, leucocrystal violet) were proposed. The sample was extracted with acetonitrile and separated on Agilent XDB C18 chromatographic column and determined by q/LTQ MS. The malachite green D5, crystal violet D6, leucomalachite green D6, and leucocrystal violet D6 were used as internal standards. Linearity ranges of the 4 compounds were found same between 0.05-5.0 μg·L-1 with detection limits (3S/N) of 0.5 μg·kg-1. Using blank samples as matrixes, test for recovery was made by standard addition method, giving recovery of the 4 compounds in the range of 93.3%-120% with RSD′s (n=6) in the range of 1.4%-18%. Furthermore, qualitative analysis for the 4 compounds was performed by applying the modes of information dependent acquisition and enhanced product ion scanning, thus attaining both identification and determination of the 4 compounds.