Benefits and Characteristic Applications of High Resolution GC/MS and LC/MS

Importance of the Topic

High-resolution GC/MS and LC/MS play a vital role in modern analytical chemistry by combining structural elucidation with selective and sensitive detection. This capability is critical for trace analysis in food safety, environmental monitoring, petrochemical characterization, natural product research and QA/QC applications.

Objectives and Overview

This work presents an integrated overview of advanced high-resolution mass spectrometry (HRMS) and tandem MS workflows, illustrating their application in pesticide residue analysis, petrochemical biomarker profiling, natural product characterization and water treatment studies. It highlights both targeted and untargeted strategies, including dynamic multiple reaction monitoring (MRM) and retrospective screening.

Applied Instrumentation

• Agilent 7200 GC/Q-TOF with high resolution and accurate mass capabilities
• Agilent 5975C GC-MSD for scan and single ion monitoring
• Agilent 1290 UHPLC coupled to triple quadrupole MS for dynamic MRM of 300 pesticides
• Agilent 6540 UHPLC Q-TOF with Jetstream ESI source
• GC-APCI-TOF and HTGC-APCI-MS for high-boiling compounds and natural products
• MassHunter Mass Profiler Professional, Molecular Feature Extractor and Molecular Structure Correlator software

Methodology

Targeted pesticide screening employed dynamic MRM on a 1290 UHPLC-QQQ platform, meeting regulatory requirements for confirmation. High-resolution TOF instruments enabled mass extraction at ±0.5 Da or ±5 ppm for GC and LC separations, supporting both scan and MS/MS modes. Untargeted workflows relied on feature extraction, multivariate analysis (PCA, PLS-DA) and formula generation from accurate isotopic patterns. MS/MS accurate mass data provided product ion spectra for structural identification and confirmation.

Main Results and Discussion

Dynamic MRM quantified 300 pesticides with two transitions each. GC-Q-TOF achieved tenfold sensitivity improvement and enhanced selectivity over GC-MSD, demonstrated in pesticide and biomarker analyses. Accurate mass extraction windows distinguished isobaric compounds such as dieldrin and endrin. Structural elucidation of a kava extract constituent (C16H14O4) was resolved by MS/MS accurate mass measurements and logical fragment matching. Petrochemical biomarker profiling (PAHs, hopanes, steranes) and natural product identification (4,8,13-duvatriene-1,3-diol, solanesol) were successfully performed. LC-QTOF profiling of egg extracts enabled identification of sulfadiazine via library and MSC scoring. Quantitation of fumonisin B1 demonstrated linearity from 400 ppt to 100 ppb. A water treatment case study identified ethinylestradiol transformation products through untargeted feature comparison.

Benefits and Practical Applications

Combined HRMS and MS/MS approaches deliver comprehensive screening and retrospective analysis, superior selectivity, enhanced sensitivity and reliable confirmation. These benefits support regulatory compliance, environmental surveillance, petrochemical forensics, natural product research and QA/QC activities.

Future Trends and Opportunities

Ongoing developments will focus on deeper integration of GC and LC HRMS, expansion of spectral libraries for untargeted workflows, advanced data mining with artificial intelligence, real-time high-throughput screening and further improvements in quantitative MRM-like workflows on HRTOF platforms.

Conclusion

High-resolution GC/MS and LC/MS combined with MS/MS technologies represent a powerful analytical toolkit that bridges targeted and untargeted methodologies. Their high selectivity, sensitivity and accuracy are indispensable for modern trace analysis in diverse fields.

References

No explicit references provided in the source material.