Analytical method of organophosphorus flame retardants in fish by ultra-high performance liquid chromatography-tandem mass spectrometry based on EMR-Lipid purification

Abstract

A method for simultaneous determination of 11 kinds of organophosphorus flame retardants in fish was established by using the EMR-Lipid cleaning agent and ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). The samples were extracted by ultrasonic with 0.5% formic acid acetonitrile solution. The lipid removal product EMR-lipid was used for lipid purification. The co-extracts were further removed by magnesium sulfate, N-propyl ethylene amine(PSA) and graphitized carbon black(GCB) purification agent. The target compounds were separated on an ACQUITY UPLC® BEH C_(18) column(100 mm×2.1 mm, 1.7 μm), detected by electrospray ionization(ESI) and positive ion multiple reaction monitoring mode, the internal standard method and external standard method are quantitatively evaluated, and external standard method was adopted. The 11 kinds of organophosphorus flame retardants had a good linear relationship in the range of 0.5-50 μg/L(tris(2-ethylhexyl) phosphate 0.05-5 μg/L) with r>0.999. The limits of detection were 0.004-1.029 μg/kg and the limits of quantitation were 0.012-3.094 μg/kg. The average recoveries at three spiked levels(low, medium and high) were 80.0%-111.2% with the relative standard deviations all less than 10%(n=6). The method could be used for the determination of trace organophosphorus flame retardants in freshwater fish with accurate and reliable result.