title: Determination of malachite green residues in rainbow trout muscle with liquid chromatography and liquid chromatography coupled with tandem mass spectrometry.
abstract: A method for the determination of malachite green and its major metabolite leucomalachite green in rainbow trout muscle is reported with limits of detection of 0.8 and 0.6 microg kg(-1), respectively. Residues were extracted with an acetonitrile-acetate buffer mixture and partitioned into methylene chloride. Clean-up of the extracts was performed on alumina and propylsulfonic acid solid-phase extraction columns using the automated solid-phase extraction system. The chromatographic separation of malachite green and leucomalachite green was achieved on a Chromspher 5B column using an acetonitrile-acetate buffer mobile phase. Leucomalachite green was converted to malachite green by post-column oxidation before spectrophotometric detection at 600 nm. The mean recoveries of malachite green and leucomalachite green from control rainbow trout muscle spiked at 2-50 microg kg(-1) were 65% (range 63.4-65.9%, relative standard deviation 3.9-16.1%) and 74% (range 58.3-82.6%, relative standard deviation 3.3-11.4%), respectively. Qualitative confirmation of the determined residues was performed with liquid chromatography coupled with tandem mass spectrometry detection with limits of detection of 2.5 and 1 microg kg(-1) for malachite green and leucomalachite green, respectively.
authors.affiliation: National Veterinary and Food Research Institute (EELA), Department of Chemistry, Helsinki, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Halme
authors.forename: E
authors.initials: E
authors.lastname: Lindfors
authors.forename: K
authors.initials: K
authors.lastname: Peltonen
mesh_terms: D000814:Aniline Compounds / Q000032:analysis; D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods*; D005659:Fungicides, Industrial / Q000032:analysis*; D018482:Muscle, Skeletal / Q000737:chemistry*; D017686:Oncorhynchus mykiss; D015203:Reproducibility of Results; D012394:Rosaniline Dyes / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D000814:Aniline Compounds; D005659:Fungicides, Industrial; D012394:Rosaniline Dyes; C005095:malachite green; C015320:leucomalachite green