Malachite Green (MG) is a fungicide frequently used in aquaculture. It is metabolized by aquatic fish and the human body into Leucomalachite Green (LMG). Both chemicals have demonstrated mutagenic (tumor) and carcinogenic results.
A highly sensitive and selective Liquid Chromatography-Mass Spectrometry (LC-MS/MS) method using the Thermo Scientific TSQ Quantum Series mass spectrometer has been developed for determining MG and LMG, yielding detection limits of <0.5µg/kg (MG + LMG) in roasted eel and other fish products.
MG and LMG can be detected by using UV-Vis and fluorescence spectrometry. However, only mass spectrometry allows for detection of both chemicals with required sensitivity and selectivity.