An Analytical Method of Paralytic Shellfish Toxins Using a Triple Quadrupole Mass Spectromete

Importance of the Topic

Paralytic shellfish toxins (PSTs) accumulate in edible bivalves and can cause severe neurotoxic effects in consumers. Rapid and accurate detection of these toxins is critical for ensuring food safety, protecting public health, and meeting international regulatory standards.

Objectives and Study Overview

This study demonstrates a hydrophilic interaction liquid chromatography–tandem mass spectrometry (HILIC LC-MS/MS) method for simultaneous analysis of twelve PST analogs in scallop samples. The goal is to replace traditional mouse bioassays with a rapid, high-throughput instrumental alternative.

Methodology and Instrumentation

The analytical workflow comprises:

• Sample Preparation: Comparison of 1% aqueous acetic acid versus 1 M HCl extraction, heat-boil treatment, centrifugation, pH adjustment, and ENVI-Carb SPE cleanup.
• Chromatography: Shimadzu Nexera™ HILIC amide column (100 mm × 2.1 mm, 1.7 µm), mobile phases of formic acid/ammonium water and acetonitrile, 10 min gradient at 0.4–0.6 mL/min, 60 °C.
• Mass Spectrometry: Shimadzu LCMS™-8060NX with ESI in positive/negative modes, optimized interface voltages, gas flows, and MRM transitions for each toxin.

Main Results and Discussion

Calibration curves for all analytes exhibited excellent linearity (R² ≥ 0.994) over 0.39–3.09 ng/mL, corresponding to 0.0004–0.0031 mg/kg in shellfish tissue. GTX2 and STX were the predominant toxins in scallop samples. The acetic acid extraction provided higher recoveries and reduced matrix suppression compared to HCl extraction.

Benefits and Practical Applications

Key advantages of the method include:

• Simultaneous quantification of twelve PST analogs within 10–15 minutes.
• Detection limits well below Codex and EU regulatory levels (0.01–0.1 mg/kg).
• Elimination of animal testing aligns with EU requirements for non-animal methods.
• Simplified LC setup allows easy integration into routine QA/QC and regulatory labs.

Future Trends and Applications

Expansion of certified reference materials for all PST analogs will enhance quantitation accuracy. Advances in automated sample preparation and high-resolution mass spectrometry could further reduce analysis time and improve throughput. Widespread adoption by international food safety authorities will standardize PST monitoring protocols.

Conclusion

The described HILIC LC-MS/MS method on the LCMS-8060NX offers a rapid, robust, and sensitive alternative to mouse bioassays for paralytic shellfish toxin analysis. Optimized acetic acid extraction ensures reliable recovery and supports the method’s implementation in routine food safety testing.

References

1. Boundy M. et al., J. Chromatogr. A, 1387, 1–12 (2015).
2. Turner A. D. et al., J. AOAC Int., 98(3), 609–621 (2015).
3. Turner A. D. et al., J. AOAC Int., 103(2), 533–562 (2020).