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Malachite green Malachite green, crystal violet (Gentian violet) is a class of synthetic the triphenylmethane industrial dye, since the 1930s as an in vitro insect repellents, fungicides and disinfectants are widely used aquatic farming. Especially in the treatment of fish proliferative kidney disease (PKD) is very effective. Malachite green and crystal violet fish absorbed mainly metabolism the LMG and colorless crystal violet, and deposited in adipose tissue. Due to animal testing potential teratogenic, carcinogenic and mutagenic effects of malachite green and crystal violet to humans and animals, has been prohibited in many countries in the world use, including China. Therefore necessary to develop a convenient and sensitive malachite green, crystal violet and their metabolites detected. This test uses state-of-the-art isotope dilution, abandon the traditional use of oxidation column, the establishment of two different aquatic matrix malachite green, crystal violet and their metabolites by liquid chromatography tandem mass spectrometry detection methods, including linear ion trap mass spectrometry and triple quadrupole mass spectrometry. Linear test, spike recovery test and the actual sample test results analysis, the assessment of methodological parameters. This test uses McIlvaine buffer and acetonitrile extraction, purification of alkaline alumina and Oasis MCX SPE column, eluent were used SRM mode (linear ion trap mass spectrometry) MRM mode (triple quadrupole mass spectrometry) detection. The results show that the linear ion trap mass spectrometry, grass carp, eel, salmon, shrimp and shellfish, the average detection limit (CCα; α1%) in between 0.02μg/kg ~ 0.09μg/kg, average limit of quantification (CCβ; beta5%) between 0.04μg/kg ~ 0.13μg/kg,. Grass carp, eel, salmon, shrimp and shellfish samples in five different spiked levels of malachite green, crystal violet and their metabolites average recovery day coefficients of variation in the range of 84.7% to 112.1%, from 1.4% to 19.8 %; triple quadrupole mass spectrometry, grass carp, eel, salmon, shrimp and shellfish average detection limit (CCα; α1%) between 0.02μg/kg ~ 0.07μg/kg average limit of quantification ( CCβ; β5%) in between 0.06μg/kg ~ 0.12μg/kg. Grass carp, eel, salmon, shrimp and shellfish samples in five different spiked levels of malachite green, crystal violet and their metabolites average recovery day coefficients of variation in the range of 84.7% to 112.1%, from 1.5% to 12.8 %. To investigate the stability of these four drugs in the sample, add at 10μg/kg the concentration of drug, to detect the residual content of the drug in different conditions the sample extract HPLC-MS/MS calculated recoveries. The results showed that the room temperature degradation phenomenon is particularly evident at -20 ° C under only a very small amount of degradation, and the more volatile colorless metabolites. TMPD or an ascorbic acid is added in the extraction process is very effective at reducing the degradation process. This issue through a large number of optimized conditions of the pre-treatment conditions and chromatography-mass spectrometry method sensitivity, accuracy and precision has been greatly improved. These four compounds are made of three sub-ion quantitative and qualitative analysis, fully meet the European Union 2002/675/EC Directive provides for the prohibited drugs Mass Spectrometry method requires the requirements of the four confirmatory points (IP) (three sub-ion 1.5IP ). Different fish samples for testing, not only the UUT accurate quantitative, but also qualitative confirmatory analyte, to provide technical support for the identification of suspected samples.
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