Validation of EPA Method 8260C on a Thermo Scientific TRACE 1300 Series GC with New Helium Saver Inlet

Importance of the Topic

Helium has become a costly and scarce resource for gas chromatography/mass spectrometry applications. Reducing helium consumption without compromising analytical performance is critical for laboratories facing rising operational expenses and supply constraints.

Aims and Study Overview

This study evaluates the combination of the Atomx automated sample preparation system’s nitrogen purge feature with the Thermo Scientific TRACE 1310 GC Helium Saver inlet. The performance is assessed according to US EPA Method 8260C for volatile organic compounds analysis, focusing on calibration accuracy, detection limits, and helium savings.

Methodology

• Sample Preparation: Calibration standards (0.5–200 ppb) prepared in deionized water with 25 ppb internal and surrogate standards via Atomx.
• Sorbent Trap: K trap used for sample enrichment and desorption.
• Carrier Gas Management: Nitrogen purge on Atomx (40 mL/min for 11 min) combined with Helium Saver inlet (purge flow 5 mL/min) to limit helium use.
• Data Processing: Thermo Scientific TraceFinder EFS software for calibration and quantitation using average response factors or 1/x weighted quadratic fits.

Instrumentation Used

• Thermo Scientific TRACE 1310 GC with Helium Saver inlet
• ISQ single quadrupole mass spectrometer
• Atomx automated sample prep system with K trap

Main Results and Discussion

• Calibration: Successful nine-point calibration for 91 target compounds; only two compounds failed acceptance criteria (0.02% failure rate).
• Method Detection Limits: MDLs ranged from 0.03 to 0.26 ppb, demonstrating high sensitivity comparable to standard helium-based methods.
• Helium Reduction: Combined approach significantly lowered helium consumption while maintaining method performance.

Benefits and Practical Applications

Using nitrogen for sample purge alongside a Helium Saver inlet offers:

• Cost Efficiency: Reduced helium usage lowers operational costs.
• Analytical Robustness: Maintains compliance with EPA Method 8260C detection and quantitation requirements.
• Workflow Integration: Compatible with existing GC/MS platforms and automated sample prep systems.

Future Trends and Potential Applications

• Expansion to Other Methods: Potential adaptation for additional volatile analyte methods beyond EPA 8260C.
• Alternative Carrier Gases: Further exploration of nitrogen in combination with hydrogen or other gases for specific applications.
• Automation and Sustainability: Integration of advanced purge controls and greener laboratory workflows.

Conclusion

The study demonstrates that the Atomx nitrogen purge feature, paired with the Thermo Scientific Helium Saver inlet, delivers reliable EPA 8260C performance while substantially reducing helium use. This approach enhances cost-effectiveness and sustainability in routine volatile organic compound analysis.

References

1. Heseltine J (2010) Hydrogen as a Carrier Gas for GC and GC–MS. LCGC North America 28(1).
2. US EPA (2006) Method 8260C Volatile Organic Compounds by Gas Chromatography/Mass Spectrometry (GC/MS), Revision 3, August.