eBook Thermo Scientific Orbitrap Exploris GC Mass Spectrometer

Importance of the topic

Gas chromatography–mass spectrometry (GC-MS) is the established workhorse for trace analysis of persistent organic pollutants such as polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pesticides and related derivatives in food, environmental and industrial matrices. However, traditional multi-residue and tandem-MS approaches require multiple acquisition methods, extensive sample preparation (e.g. Soxhlet extraction), long run times (>30 min) and complex method optimization. High-resolution, accurate-mass (HRAM) Orbitrap™-based GC-MS in full-scan mode offers the selectivity, sensitivity, dynamic range and speed to consolidate multi-class analyses into a single fast method, reduce instrument downtime, simplify workflow and enable retrospective screening of unknowns with high confidence.

Objectives and overview of the study

This summary integrates a series of Thermo Scientific eBooks, application notes and case studies on the Orbitrap Exploris™ GC mass spectrometer. Key aims were to:

• Evaluate full-scan HRAM GC-MS performance for analytical testing and scientific research (resolution, mass accuracy, scan rate, dynamic range).
• Assess quantitative application to multi-residue pesticide and PCB analysis in food at EU MRL levels (10 µg/kg), including ion ratio and mass accuracy confirmation.
• Demonstrate profitability and productivity benefits in high-throughput laboratories through method consolidation and uptime maximization.
• Test robustness via 500 repeat injections of PAH and PCB spiked soil extracts to gauge long-term stability of response, RRF, ion ratios and mass accuracy.
• Show streamlined consolidated QuEChERS sample prep and <20 min GC separation of 45 PCBs, PAHs, methyl/Oxy/NSO-PAHs in soil.
• Illustrate retrospective unknown screening and confirmation using deconvoluted EI spectra and positive chemical ionization (PCI) for molecular ion validation.

Methodology and instrumentation used

Sample preparation focused on modified QuEChERS extraction and dispersive SPE cleanup for fruits, vegetables and soil. Chromatographic separation was performed on Thermo Scientific TRACE™ 1310/1300 Series GCs with Instant-Connect split/splitless (SSL) injectors and TraceGOLD™ TG-5SilMS or equivalent capillary columns, using 20 min temperature programs. Automated liquid injection was achieved with the TriPlus™ RSH autosampler. The GC was hyphenated to a Thermo Scientific Orbitrap Exploris GC mass spectrometer fitted with a removable ExtractaBrite™ EI/PCI source and high-field Orbitrap™ analyzer. Full-scan data (m/z 50–550 or 65–690) were acquired at 60,000 FWHM (200 m/z) or up to 240,000 in special applications, at up to 40 Hz scan speed. Calibration and tuning were completed in under 2 minutes without venting. Data processing and reporting utilized Thermo Scientific Chromeleon™ CDS (quantitation, ion ratio checks, system suitability, Intelligent Run Control) and Compound Discoverer™ for deconvolution, library matching and unknown identification.

Main results and discussion

• Sensitivity and dynamic range: MDLs of 118–475 fg on column (0.1–0.5 µg/kg in soil); LOQs of 0.1–1 pg on column (0.1–1 µg/kg) with <15% RSD, ion ratios ±30% tolerance. Six orders of magnitude linearity (0.1–10 000 pg on column) with R2 ≥ 0.995.
• Quantitative food testing: Multi-residue pesticide and PCB analysis in apples, carrots and baby food achieved EU MRLs (10 µg/kg) with mass accuracy <2 ppm, ion ratio stability, RRF precision <15% and recoveries 60–140% in SANTE validation.
• Robustness: 500 repeat injections of QuEChERS soil extract spiked at 10 pg/µL (ppb) showed <10% RSD in peak area response for PAHs/PCBs over three weeks unattended operation, RRF RSD <5% and mass accuracy <1 ppm without column trimming or venting.
• Consolidated soil screening: Single GC-MS run (<20 min) separated 45 PCBs, PAHs, methyl/Oxy/NSO-PAHs in soil with excellent critical pair resolution, EP asymmetry ~1.0, and <5 pg MDLs.
• Unknown identification: EI deconvolution and NIST library matching identified 50+ environmental contaminants in soil extracts. PCI enabled molecular ion adduct confirmation ([M+H]+, [M+C2H5]+) with <1 ppm mass error, confirming pesticide hits such as flutolanil and pyriproxyfen.

Benefits and practical applications of the method

• Method consolidation: Single HRAM GC-MS method replaces multiple targeted SIM/SRM methods, reducing instrument count, consumables, bench space and maintenance.
• High throughput and profitability: <20 min runs, automated QC checks, minimal maintenance and walk-up operation maximize uptime and deliver rapid turnaround.
• Flexible scope: Full-scan acquisition allows post-acquisition selection of any analyte of interest, retrospective screening and rapid addition of new compounds without re-optimization.
• Enhanced selectivity and confidence: High resolution resolves coeluting interferences; accurate mass and ion ratio checks minimize false positives/negatives;
• Regulatory compliance: Data meets EU SANTE/12682/2019 criteria for HRAM GC-MS residue analysis in food and environmental samples.

Future trends and application possibilities

• Expansion of HRAM GC-MS into emerging contaminant monitoring (NSO-PAHs, chlorinated hydrocarbons, halogenated flame retardants) with comprehensive spectral libraries.
• Integration of AI-driven data analytics and automated library searching for rapid screening and unknown identification in complex matrices.
• Enhanced sample preparation automation (online QuEChERS, SPME, SPE) coupled with HRAM GC-MS for trace-level profiling in environmental and metabolomics studies.
• Laboratory network integration using enterprise CDS platforms to centralize data, automate QC and facilitate multi-site compliance with GLP/GMP and 21 CFR Part 11.

Conclusion

The Thermo Scientific Orbitrap Exploris GC mass spectrometer delivers transformative high-resolution accurate-mass GC-MS capabilities for analytical testing and research. It combines full-scan sensitivity, mass accuracy (<1 ppm), robust quantitative performance, and rapid method setup to consolidate multi-class analyses into fast workflows with minimal downtime. These advantages enable laboratories to increase throughput, reduce costs, maintain regulatory compliance and adapt dynamically to evolving analytical demands across food safety, environmental monitoring, industrial QA/QC and beyond.

Instrumentation Used

• Thermo Scientific Orbitrap Exploris™ GC hybrid quadrupole-Orbitrap mass spectrometer with ExtractaBrite™ EI/PCI source and NeverVent™ technology
• Thermo Scientific TRACE™ 1310/1300 Series Gas Chromatograph with Instant-Connect injectors (SSL/PTV) and TraceGOLD™ TG-5SilMS columns
• Thermo Scientific TriPlus™ RSH autosampler with LinerGOLD™ liners
• Thermo Scientific Chromeleon™ 7.3 CDS, TraceFinder™, and Compound Discoverer™ 3.2 software

References

• Thermo Fisher Scientific White Paper WP-10456, “The Power of High Resolution Accurate Mass Using Orbitrap-Based GC-MS,” 2015.
• Application Note 10449, “Fast Screening of Pesticide Residues in Baby Food by GC-Orbitrap MS,” Thermo Fisher Scientific.
• Application Note 10509, “Routine Quantitative Pesticide Analysis Using GC-Orbitrap MS,” Thermo Fisher Scientific, 2016.
• Application Note 10724, “Breakthrough Performance of the Orbitrap Exploris GC for Analytical Testing and Scientific Research,” Thermo Fisher Scientific, 2020.
• Technical Note 10728, “Robust Analysis of PAHs and PCBs in Soil with 500 Injects Using Orbitrap Exploris GC,” Thermo Fisher Scientific, 2020.
• Application Note 10731, “Consolidated Analysis of Soil Contaminants by QuEChERS and GC-Orbitrap,” Thermo Fisher Scientific, 2020.