Analysis of 18 Polycyclic Aromatic Hydrocarbons (PAHs) Using a Hypersil Green PAH Column

Significance of the Topic

The analysis of polycyclic aromatic hydrocarbons (PAHs) is critical due to their classification as priority environmental pollutants and recognized carcinogens. Efficient separation and quantification of PAHs in air, soil, and water samples support regulatory compliance, risk assessment, and remediation efforts. High-resolution chromatographic methods enable accurate monitoring of both EPA-listed PAHs and emerging compounds of concern.

Objectives and Study Overview

This study aimed to demonstrate the capability of the Thermo Scientific Hypersil Green PAH HPLC column to separate eighteen PAH congeners, including the sixteen compounds specified by EPA Method 610 plus benzo[e]pyrene and benzo[j]fluoranthene. Particular focus was placed on achieving baseline resolution between structurally similar isomers.

Methodology

• Sample preparation: A 16-PAH standard at 10 µg/mL in acetonitrile was supplemented with single-component standards of benzo[e]pyrene and benzo[j]fluoranthene at equivalent concentration.
• Chromatographic conditions: Hypersil Green PAH column (5 µm, 150 × 4.6 mm) operated at 30 °C and 1 mL/min flow rate under a binary gradient (60% to 100% acetonitrile over 30 min, then re-equilibration).
• Injection and detection: 10 µL injection volume; UV detection at 225 nm; system backpressure ~90 bar at method start.

Used Instrumentation

• Thermo Scientific Accela UHPLC System
• Hypersil Green PAH column, 5 µm, 150 × 4.6 mm
• UV detector set at 225 nm

Main Results and Discussion

All eighteen PAHs eluted within a 30-minute analysis window. The critical isomer pair benzo[e]pyrene and benzo[j]fluoranthene achieved baseline separation, illustrating the column’s selectivity. Replicate injections (n=6) yielded retention time %RSD values below 0.1%, and resolution factors between adjacent peaks consistently surpassed baseline criteria. These performance metrics highlight both the efficiency and reproducibility of the Hypersil Green PAH phase.

Benefits and Practical Applications

• Rapid, high-resolution analysis compliant with EPA Method 610 and expanded monitoring lists.
• Robust retention time reproducibility supports routine environmental testing and QA/QC workflows.
• Broad chemical coverage allows simultaneous quantification of parent PAHs and emerging isomers.

Future Trends and Opportunities

Integration of this chromatographic approach with tandem mass spectrometry could enhance detection limits and compound specificity. Further miniaturization and adoption of UHPLC columns may reduce run times and solvent consumption. Ongoing development of tailored stationary phases and greener mobile phases will address challenges in isomeric separation and sustainability in environmental analysis.

Conclusion

The Thermo Scientific Hypersil Green PAH column delivers fast, high-resolution separation of eighteen PAHs, including extended target analytes beyond the EPA list. Its reproducible performance and compatibility with standard environmental protocols make it a valuable tool for laboratories conducting routine PAH monitoring.