RESUMEN
The particles suspended in seawater have great influence on pollutant migration and transformation in marine environment, while the lipophilic algae toxins enriched by the particles suspended in seawater will lead more serious toxicity to marine filter feeders. In this study, a new method was developed for the simultaneous determination of eight lipophilic algae toxins in suspended particles by ultra performance liquid chromatography-tandem mass spectrometry ( UPLC-MS/MS ) . After extracted with methanol by ultrasonic-assisted extraction, the sample was separated on an Acquity UPLC BEH C18 column (50 mm×2. 1 mm, 1. 7 μm) using gradient elution of acetonitrile and water containing 5 mmol/L ammonium acetate as eluent modifiers. The qualitative and quantitative analyses were carried out by electrospray ionization ( ESI) tandem mass spectrometry in multiple reaction monitoring ( MRM) mode. Under the optimal conditions, satisfactory precision (relative standard deviations (RSD≤14. 1%), recoveries (83. 8%-110. 4%) and detection limits (2. 9-103 pg/g) of the method were achieved. Good linearity (R2≥0. 99) was also obtained for all studied analytes. Then, the method was applied to determine the amounts of the eight lipophilic marine toxins in authentic suspended particle samples collected from Qingdao near-shore area. Pectenotoxin 2 ( PTX2 ) was detected in the samples from Shilaoren beach and No. 3 bathing beach with concentration ranges of 717 and 790 pg/g, respectively.