A Direct 5 ms Column Performance Comparison for Active Semi-Volatile Analytes

Importance of the topic

Capillary gas chromatography analysis of semi-volatile environmental analytes requires high column inertness to avoid peak tailing, adsorption and loss of sensitivity for active compounds such as benzoic acid, 2,4-dinitrophenol, aniline and benzidine. Consistent inert performance ensures reliable quantification at trace levels and reduces reanalysis costs.

Study objectives and overview

This work compares inertness performance of two premium 20 m × 0.18 mm × 0.18 μm 5 ms GC columns: Agilent J&W HP-5ms Ultra Inert and Vendor R Rxi-5ms. The study aims to evaluate peak shapes, recovery and relative response ratio (RRR) for a standard semi-volatile mix modeled on EPA Method 8270D.

Methodology and used instrumentation

• GC system: Agilent 6890N network GC with 5975B MSD detector
• Sampler: Agilent 7683B autosampler, splitless injection (0.5 μL)
• Inlet: Deactivated direct connect liner at 280 °C
• Carrier gas: Helium ramped from 0.7 to 1.3 mL/min
• Oven program: initial 35 °C, ramp to 300 °C in multi-step sequence
• Columns: two 20 m × 0.18 mm × 0.18 μm formats from Agilent and Vendor R
• MSD conditions: source 300 °C, quad 180 °C, scan 50–550 m/z

Main results and discussion

• Agilent column delivered sharp, symmetric peaks for acidic and basic analytes at 0.5 ng loading, while Vendor R showed pronounced tailing and reduced responses.
• RRR for 2,4-dinitrophenol on Agilent columns averaged 0.192–0.198, well above the 0.05 minimum, compared to 0.144–0.146 for Vendor R, indicating faster loss of inertness on Vendor R.
• Faster analysis: the 5 ms phase column provided equivalent resolution to a conventional 30 m × 0.25 mm column with 30–40% time savings.

Benefits and practical applications

• Reliable peak shapes and quantitation for active environmental contaminants.
• Improved throughput and lower per-sample cost by using high-efficiency fast columns.
• Reduced reanalysis and maintenance by ensuring consistent inertness through rigorous testing.

Future trends and application opportunities

• Development of even more inert stationary phases and advanced surface treatments.
• Integration with software for automated method translation and real-time inertness monitoring.
• Expansion of fast high-efficiency columns to other compound classes and multidimensional GC workflows.

Conclusion

A direct comparison demonstrates that Agilent J&W HP-5ms Ultra Inert columns maintain superior inertness, peak shape and sensitivity for semi-volatile analytes compared to Vendor R Rxi-5ms. Fast 5 ms columns offer robust performance and increased laboratory productivity for environmental GC/MS analyses.

References

1. US EPA Method 8270D Revision 4, Semivolatile Organic Compounds by GC/MS, 2007.
2. M. Hastings et al., Inertness Comparison of 5% Phenyldimethylpolysiloxane Columns, Pittcon, 2003.
3. J. Luong et al., Advanced Solventless Column Test for Capillary GC Columns, J. Sep. Sci., 2007, 30, 2480–2492.
4. Agilent J&W Ultra Inert GC Columns Technical Overview, 5989-8685EN, 2008.
5. Agilent Method Translation Software, www.agilent.com/chem/gcmethodtranslation.