PARTICLE-BEAM LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY OF TRIPHENYLMETHANE DYES - APPLICATION TO CONFIRMATION OF MALACHITE GREEN IN INCURREDCATFISH TISSUE

Eight triphenylmethane dyes (malachite green, leucomalachite green, ge ntian violet, leucogentian violet, brilliant green, pentamethyl gentia n violet, N',N ''-tetramethyl gentian violet and N',N ''-tetramethyl g entian violet) have been characterized by particle beam liquid chromat ography-mass spectrometry. The electron ionization spectra obtained of these dyes by this technique exhibit similar fragmentation, with the formation of phenyl and substituted phenyl radicals, and loss of alkyl groups from the amines. It was observed that the six cationic dyes ar e reduced in the mass spectrometer source to form the corresponding le uco compounds. This technique was evaluated for the confirmation of ma lachite green and leucomalachite green in incurred catfish (Ictalurus punctatus) muscle tissue.