Rapid Screening and Identification of Paralytic Shellfish Poisoning Toxins in Red Tide Algae Using Hydrophilic Interaction Liquid Chromatography-High Resolution Mass Spectrometry with an Accurate-Mass Database

Abstract

In this study, a new method was developed for the rapid screening and identification of paralytic shellfish poisoning (PSP) toxins in red tide algae by hydrophilic interaction liquid chromatography-high resolution mass spectrometry (HILIC-HR-MS) combined with accurate mass database. Toxic algae sample was extracted with 0.1 M acetic acid after cell-breaking, and then the crude extracts were analyzed by HILIC-HR-MS in positive and negative full scan modes. The accurate mass of quasi-molecular ion and main fragment ion peaks of PSP toxins in toxic algae were acquired and the PSP toxins in algae could be successfully qualitated by database screening and HR-MS data analysis using commercial software (Masshunter). The created database includes data not only the accurate relative molecular masses of 25 common PSP toxins but also the fragment ions. The results showed that the proposed HILIC-HR-ESI/MS method has high sensitive and separation efficiency. The limits of detection (LOD) of ten common PSP compounds were in the range of 10–80 nM, and it could meet the requirements for the actual screening of toxic algae samples. The developed method was applied to screen the PSP toxins in three kinds of toxic algae which demonstrated that the method was a useful tool for the rapid screening and qualitative identification of common PSP toxins in harmful algae.