Versatile, highly sensitive and reproducible: How Orbitrap Exploris GC 240 strengthens metabolomics

Significance of the Topic

Metabolomics provides a comprehensive snapshot of small molecules that reflect an organism’s genetic and environmental interactions. High-resolution mass spectrometry combined with gas chromatography expands the range of detectable metabolites, particularly volatile and thermally labile compounds, enabling deeper insights into biomarker discovery, environmental exposure assessment, and translational research.

Study Objectives and Overview

The Bowden laboratory at the University of Florida aimed to broaden its metabolomic capabilities by integrating high-resolution GC-MS into existing LC-MS workflows. Key goals included:

• Assessing the impact of environmental pollutants on human and wildlife health.
• Identifying internal biomarkers of exposure alongside external pollutant measurements.
• Developing robust, reproducible workflows for both nontargeted and targeted metabolomic studies.

Methods and Used Instrumentation

The laboratory incorporated the Orbitrap Exploris GC 240 system for its superior resolution, mass accuracy (<1 ppm), and sensitivity without sacrificing selectivity. Workflow optimization included:

• Sample preparation: tailored extraction and derivatization protocols for various matrices (plasma, urine, wildlife tissues).
• Chromatographic separation: leveraging GC for volatile and semi-volatile compounds complementary to LC for polar analytes.
• Data acquisition: high-resolution full-scan and tandem MS strategies for structural elucidation and quantitation.
• Software tools: Compound Discoverer for spectral deconvolution, library searches against NIST/Wiley databases, and an in-house GC-MS HRAM metabolomics library.

Main Results and Discussion

Implementation of the Orbitrap Exploris GC 240 enabled the laboratory to:

• Capture a broader chemical space in a single injection, from PFAS pollutants to amino acid derivatives.
• Achieve consistent, inter-user reproducibility through automated methods and intelligent run controls.
• Identify unknowns in non-model species by combining high mass accuracy with extensive spectral libraries.

Parallel projects demonstrated the platform’s versatility:

• PFAS exposomics in marine mammals (e.g., manatees) and indoor air samples.
• Lupus cohort studies in Gullah African American patients using plasma and urine metabolomics.
• Wildlife exposure assessments across diverse taxa, including crocodilians and fish.

Benefits and Practical Applications

The combined GC-MS and LC-MS workflow offers:

• Comprehensive profiling of both volatile and nonvolatile metabolites.
• Accelerated biomarker discovery for environmental and disease studies.
• Enhanced data quality and confidence through high-resolution accurate-mass detection.
• Streamlined adoption by laboratories via standardized reference materials and published protocols.

Future Trends and Opportunities

Emerging directions include:

• Community-wide standardization of metabolomic measurements using shared SRMs and data-sharing platforms.
• Expansion of spectral libraries for rare and non-model organisms to support exposomics.
• Integration of automated sample preparation and machine-learning-driven data analysis for higher throughput.
• Application of GC-MS exposomics to new environmental challenges, such as landfill emissions and indoor pollutants.

Conclusion

By adopting the Orbitrap Exploris GC 240, the Bowden laboratory has achieved a unified, high-resolution workflow that bridges pollutant analysis and biomarker discovery. This versatile platform delivers reproducible, sensitive, and comprehensive metabolomic data, opening new avenues for environmental health research and translational applications.