Determination of neurotoxic shellfish poisoning toxins in shellfish by liquid chromatography-tandem mass spectrometry coupled with dispersive solid phase extraction.

An innovative method based on dispersive solid phase extraction (d-SPE) in conjunction with LC-MS/MS had been developed for the simultaneous quantitative determination of three brevetoxins (BTXs), which can result in neurotoxic shellfish poisoning (NSP), in shellfish. The toxins were extracted with a 50 % acetonitrile (v/v) and cleaned by alumina-neutral sorbent. After chromatographic separation on a C column, the analytes were qualitatively and quantitatively detected using multiple reaction monitoring (MRM) in positive ionization mode. The created approach was validated by SANTE 11312/2021. The LOQs were 5 μg/kg for each toxin, below the advised regulatory limit of 800 μg BTX-2/kg. The mean recoveries of brevetoxins were in the range of 75.9 %-114.1 %, and the ranges of their intra- and inter-day precisions were 0.9-9.7 % and 0.6-7.2 %, respectively. The matrix effects for three BTXs in four shellfish matrices were in the range of 85.6 %-114.8 %. The method demonstrated great consistency and high sensitivity, and it can meet the requirements of daily monitoring.