1Figure 1. ACQUITY UPLC H-Class System with FLR.Ensuring Seafood Safety with Rapid Screening for Polyaromatic Hydrocarbons Using LC-Fluorescence

Significance of the Topic

This application addresses the urgent need for rapid screening of polyaromatic hydrocarbons (PAHs) in seafood following major oil spills. PAHs are priority pollutants with established regulatory limits, and fast, reliable methods are essential to protect public health and maintain confidence in the seafood industry.

Objectives and Study Overview

The study demonstrates a combined approach using QuEChERS dispersive extraction and ultra-performance liquid chromatography with fluorescence detection (UPLC-FLR) to screen 15 priority PAHs in fish, shrimp, and oyster tissues in under four minutes per analysis.

Methodology and Instrumentation

• Sample Preparation: Homogenized seafood samples were spiked at three concentration levels and extracted using Waters DisQuE dispersive sample preparation (6 g MgSO4, 1.5 g NaOAc, 15 mL acetonitrile) without secondary PSA cleanup. Supernatants were directly injected after appropriate dilution.
• Chromatographic Conditions: An ACQUITY UPLC H-Class System equipped with a large-volume flow cell and fluorescence detector was used. Separation employed a PAH column (4.6 × 50 mm, 3 µm) at 35 °C, 2.0 mL/min, with a rapid gradient (30% water to 100% acetonitrile in 3.5 min) and timed wavelength switching for optimal detection of each PAH.
• Data Processing: Empower 2 software generated six-point calibration curves and quantified samples. Linearity (R2) exceeded 0.995 for all analytes.

Main Results and Discussion

Complete baseline separation of all 15 PAHs was achieved in 3.5 minutes. Chromatograms of spiked matrices at 10 µg/g showed clear, interference-free peaks, and unspiked controls confirmed negligible matrix effects. Recoveries ranged from 68% to 149% across matrices, with RSD values generally below 10%. Estimated limits of detection spanned 0.2 ng/g to 5 ng/g depending on compound and matrix, meeting regulatory requirements.

Benefits and Practical Applications

This workflow significantly reduces both sample preparation and analysis time compared with traditional methods. The selective fluorescence detection enhances sensitivity and specificity without extensive cleanup. Laboratories can implement this rapid screening to ensure seafood safety, expedite compliance decisions, and reduce operational costs.

Future Trends and Opportunities

Advancements may include full automation of sample preparation, integration with high-resolution mass spectrometry for broader contaminant profiling, and application to other food and environmental matrices. Enhanced data analytics and remote monitoring platforms could further streamline routine surveillance and regulatory reporting.

Conclusion

The integration of QuEChERS dispersive extraction and UPLC-FLR provides a robust, high-throughput method for screening priority PAHs in seafood. Achieving reliable separations in under four minutes with strong recoveries and low detection limits supports effective monitoring and public health protection.

References

1. USEPA Method 8310 Rev. 0, Polycyclic Aromatic Hydrocarbons, September 1986.
2. Gratz et al., Screening for PAHs in Seafood Using LC-FLR, USFDA Laboratory Information Bulletin, July 2010.
3. Ramalhosa et al., Journal of Separation Science, 2009, 32:3529–3538.
4. Anastassiades et al., Journal of AOAC International, 2003, 86(2):412–431.
5. EPA 40 CFR, Appendix B to Part 136 Rev 1.1.