title: Determination of malachite green residues in fish using molecularly imprinted solid-phase extraction followed by liquid chromatography-linear ion trap mass spectrometry.
abstract: This paper describes the development of an analytical procedure to determine malachite green (MG) residues in salmon samples using molecularly imprinted polymers (MIPs) as the extraction and clean-up material, followed by liquid chromatography-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS). MG and two structurally related compounds, crystal violet (CV) and brilliant green (BG) were employed for the selectivity test. The imprinted polymers exhibited high binding affinity for MG, while CV and BG showed less binding capacity: 47% and 34%, respectively. The recovery values of MG in salmon samples fortified with leucomalachite green (LMG) were determined by measuring the amount of MG in the sample, after carrying out the oxidation reaction with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), which converts the LMG back into chromic-form. The average recovery of MG in spiked salmon muscle over the concentration range 1-100 ng g(-1) was 98% with a relative standard deviation value (R.S.D.) below 12%. The method detection limits (MDLs) obtained for MG, CV, BG and their leuco-metabolites were in the range of 3-20 ng kg(-1) (ppt).
authors.affiliation: Pesticide Residues Research Group, Department of Hydrogeology and Analytical Chemistry, University of Almería, 04120 La Cañada de San Urbano, Almería, Spain.
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Martínez Bueno
authors.forename: Sonia
authors.initials: S
authors.lastname: Herrera
authors.forename: Ana
authors.initials: A
authors.lastname: Uclés
authors.forename: Ana
authors.initials: A
authors.lastname: Agüera
authors.forename: María Dolores
authors.initials: MD
authors.lastname: Hernando
authors.forename: Olga
authors.initials: O
authors.lastname: Shimelis
authors.forename: Marcus
authors.initials: M
authors.lastname: Rudolfsson
authors.forename: Amadeo R
authors.initials: AR
authors.lastname: Fernández-Alba
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005840:Gentian Violet / Q000032:analysis / Q000302:isolation & purification; D054802:Molecular Imprinting; D000644:Quaternary Ammonium Compounds / Q000032:analysis / Q000302:isolation & purification; D012394:Rosaniline Dyes / Q000032:analysis* / Q000302:isolation & purification; D012474:Salmon / Q000378:metabolism; D052616:Solid Phase Extraction; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D000644:Quaternary Ammonium Compounds; D012394:Rosaniline Dyes; C005095:malachite green; C015320:leucomalachite green; C006798:brilliant green; D005840:Gentian Violet