Objective: An ultra performance liquid chromatography-hybrid triple quadrupole linear ion trap-mass spectrometry(UPLC-QqLIT-MS) was established for determination of lipophilic marine biotoxins in shellfish. And the 12 lipophilic marine biotoxins in shellfish were surveyed.
Methods: The lipophilic marine biotoxins in homogenized shellfish were ultrasonically extracted by methanol in super-sonic instrument, and cleaned up by solid phase extraction of Strata-X column, and eluted with methanol(containing 0.3% ammonia water). The elution was diluted with water, and cleaned by 0.22 μm millipore filter. The filtrate was separated on a Waters ACQUITY UPLC BEH C_(18) column(150 mm×2.1 mm, 1.7 μm)by gradient elution in 12 minutes with acetronitrile-water(containing 0.01%(V/V) ammonia and 2 mmol/L ammonium formate) as mobile phase, and detected by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS), identified by electrospray ionization(ESI) in simultaneous scanning mode of positive and negative ions using multiple reaction monitoring, and quantified with external standards. Information dependent acquisition scan function(IDA) combined with enhanced production scan(EPI) was used to confirm the 12 lipophilic marine biotoxins.
Results: The calibration curves of 12 lipophilic marine biotoxins showed good linearity in the range of 0.5-50 μg/L with correlation coefficients were 0.9984-0.9999.The detection limits of the method were 0.15-0.29 μg/kg. The recoveries of three spiking levels ranged from 80.0% to 116.0%, and the relative standard deviation(RSD) were 0.6%-6.4%(n=7).
Conclusion: The method for determination of 12 lipophilic marine biotoxins in shellfish by UPLC-QqLIT-MS was of operation convenience, less interference from impurities and good accuracy, which could meet the requirements for the determination of 12 lipophilic marine biotoxins residues in sea foods.
Keywords: hybrid triple quadrupole linear ion trap-mass spectrometry(QqLIT-MS); lipophilic marine biotoxins; shellfish.