Breakthrough Analytical Performance of a Novel Gas Chromatography –Orbitrap Mass Spectrometry for Routine and Research Applications

Importance of the Topic

The combination of gas chromatography with high-resolution accurate mass spectrometry delivers powerful capabilities for both routine analytical testing and advanced research. The Orbitrap Exploris GC system enhances sensitivity, mass accuracy, dynamic range, and spectral fidelity, enabling trace-level quantitation and confident compound identification in complex matrices.

Objectives and Study Overview

This study evaluates the analytical performance of the Thermo Scientific Orbitrap Exploris GC 240, focusing on key parameters: mass accuracy, resolving power, scan speed, linear dynamic range, sensitivity, library matching, spectral fidelity, and robustness. Its goal is to demonstrate suitability for regulatory, QA/QC, and research applications.

Methodology and Instrumentation

A benchtop Orbitrap Exploris GC 240 was operated at resolving powers up to 240 000 (FWHM at m/z 200). Chromatographic separation used a TG-5SilMS capillary column with split/splitless injection. Both electron ionization (EI) and positive chemical ionization (CI) (methane) modes were employed. Lock-mass correction utilized siloxane background ions. Data acquisition in full scan mode at 30 k–240 k resolution was processed with TraceFinder and Compound Discoverer software.

Main Results and Discussion

The system delivered:

• Fast scan rates achieving ~15 data points across a 2.3 s GC peak, ensuring precise peak definition.
• Sub-ppm mass accuracy (<1 ppm) maintained across individual scans and concentration levels.
• A linear dynamic range spanning six orders of magnitude (0.1–10 000 pg on-column) with R² > 0.99 for hexachloroethane.
• Instrument detection limits between 0.18 and 2.45 pg/μL for over 140 pesticides in a flour matrix (average 0.7 pg/μL).
• High NIST library forward and reverse match scores (>750) for mixed pesticide standards in complex matrix.
• Consistent spectral fidelity, illustrated by <1 ppm isotope cluster mass error and 100 % isotope match score for pentachloroaniline at both low and high levels.

Benefits and Practical Applications

The Orbitrap Exploris GC enables reliable screening and quantification of regulatory contaminants (e.g., pesticide residues), supports metabolomics and environmental analysis, and ensures trace detection with high confidence via accurate mass library matching.

Future Trends and Applications

Advancements in data-processing algorithms and real-time library searching will further enhance non-targeted screening, stable isotope tracing, and high-throughput workflows. Integration with orthogonal separation techniques and AI-driven interpretation will expand research and QA/QC capabilities.

Conclusion

The Orbitrap Exploris GC mass spectrometer offers exceptional analytical performance—combining sub-ppm mass accuracy, fast scan speeds, broad dynamic range, and robust spectral matching—making it a transformative platform for both routine and research-focused GC-MS applications.

References

1. Thermo Scientific White Paper 10456, The Power of High Resolution Accurate Mass Using Orbitrap Based GC-MS, May 2015.
2. Thermo Scientific Application Note 10449, Fast Screening, Identification, and Quantification of Pesticide Residues in Baby Food Using GC Orbitrap MS Technology.