Simultaneous determination of 13 paralytic shellfish toxins and tetrodotoxin in marine shellfish by porous graphitic carbon solid-phase extraction and hydrophilic interaction chromatography-tandem mass spectrometry

Abstract

The lethal neurotoxins, paralytic shellfish toxins (PSTs), and tetrodotoxin (TTX) have recently been found in marine shellfish from many coastal states. Herein, we applied a sensitive and reliable ultra-performance hydrophilic interaction chromatography (HILIC)-tandem mass spectrometry (MS) method to determine 13 PSTs and TTX in marine shellfish using a porous carbon solid-phase extraction (SPE). This in-house validation study required the development of a novel chromatographic separation using a HILIC-Z column, which was necessary to retain highly polar compounds. Using acetonitrile as the organic phase and ammonium formate-formic acid buffer as the aqueous phase, the quantitative analysis was carried out with an external standard method in the multiple reaction monitoring modes using positive electrospray ionization. To reduce interference, 1% aqueous acetic acid extracts of the shellfish samples were cleaned up by ion-pair SPE using a porous graphitic carbon cartridge. The calibration curves for PSTs and TTX were linear (R² > 0.995), and the sensitivity was good, with limits of detection (LODs) of 1.7–13.7 µg/kg, and limits of quantitation (LOQs) of 5.2–41.0 µg/kg. The recoveries were 76.5–95.5% with RSDs of 3.1–12.0%. Finally, We applied the method for the determination of PSTs and TTX in three batches of Nassarius showing excellent method accuracy against expected values.

Keywords:

• LC-MS/MS
• PSTs
• TTX
• hydrophilic interaction chromatography (HILIC)

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by Zhejiang Province Welfare Technology Applied Research Project under Grant No. LGC20H260001, Zhejiang Province Public Welfare Technology Research Plan/Analysis and Test Project (No. LGC20B050007), Zhejiang Key Research and Development Program (No. 2021C02061), and National Natural Science Foundation of China under Grant No. 81501808.