Molecularly imprinted polymer solid phase extraction coupled with liquid chromatography-high resolution mass spectrometry for the detection of gonyautoxins 2&3 in seawater.

Paralytic shellfish toxins (PSTs) cause risks to human health through food chains. Understanding the change of PSTs in seawater is critical for predicting the safety of seafood. Most reported methods for the detection of PSTs in microalgae or shellfish are not applicable in seawater because of extremely low concentration and matrix interferences. High resolution mass spectrometry (HRMS), quadrupole exactive orbitrap detects molecular ions accurately, and molecularly imprinted solid-phase extraction (MISPE) is recognized effective to reduce the matrix interference. GTXs 2&3 are two of common marine toxins in PSTs. In this study, a sensitive method consisting MISPE and liquid chromatography LC-HRMS was developed for the detection of GTXs 2&3 with a limit of detection (LOD) of 47.4 ng/L in seawater. With this method, samples obtained from the estuaries of the Shuangtaizi and Daliao Rivers were analyzed, and the results indicated the concentrations were lower than LOD in the area under investigation.