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

Significance of the Topic

High‐resolution gas chromatography–mass spectrometry (GC/MS) and liquid chromatography–mass spectrometry (LC/MS) are cornerstones of modern analytical chemistry. They enable precise structure elucidation, selective detection of target compounds, trace‐level quantification and retrospective data mining. These capabilities support critical applications such as food safety, environmental monitoring, petrochemical fingerprinting and natural product characterization.

Aims and Study Overview

This work surveys recent advances in high‐resolution GC/MS and LC/MS instrumentation and methodologies. It illustrates how accurate mass measurement, high sensitivity and mass spectral libraries deliver robust targeted analysis (MRM‐style) as well as untargeted screening. Case studies cover pesticide residue analysis in food, structure confirmation of bioactive compounds, biomarker profiling in crude oil, mycotoxin quantification in egg extracts and water treatment byproduct identification.

Methodology and Instrumentation

An integrated suite of chromatographic and mass spectrometric platforms was employed:

• GC/Q‐TOF (Agilent 7200) for accurate mass measurement, high selectivity and retrospective screening in open methods.
• GC‐MS (5975C MSD) in scan and selected ion monitoring (SIM) modes for comparison of sensitivity and selectivity.
• UHPLC‐QTOF (1290 Infinity II coupled to 6540 Q‐TOF) with JetStream ESI for enhanced sensitivity (up to 10×) and high‐resolution accurate mass analysis.
• High‐temperature GC‐APCI‐QTOF for high‐mass natural product screening (e.g. C10–C40 fractions, hopanes, steranes) using APCI interfaces and HTGC columns.
• Software tools including MRM simulation, Molecular Feature Extraction, Mass Profiler Professional for multivariate statistics, Molecular Structure Correlator and custom accurate mass and MS/MS libraries.

Main Results and Discussion

General trend in trace analysis moved from SIM to dynamic MRM on triple quadrupoles and Q‐TOF MRM mimic. A dynamic MRM method quantified 300 pesticides with two transitions each at regulatory levels (<10 µg/kg). GC/Q‐TOF enabled accurate‐mass extracted ion chromatograms (±5 ppm) with signal‐to‐noise improvements (>10×) compared to conventional MSD. Retrospective data mining revealed non‐target pesticides and emerging contaminants in food extracts. In structure elucidation, MS/MS accurate mass data discriminated isomeric candidates in kava extracts by matching fragment formulas within 1–3 ppm. Petrochemical biomarker profiling in crude oil used high‐resolution EICs at ±5 ppm to resolve hopanes and steranes, while MS/MS confirmed fragment relationships. In LC‐QTOF water study, untargeted feature extraction and PCA identified chlorination byproducts (e.g. brominated phenolics) down to sub‐ppb levels. Quantitative mycotoxin analysis achieved linearity from 400 ppt to 100 ppb on-column.

Benefits and Practical Applications

• High selectivity via accurate mass reduces interferences and false positives.
• High sensitivity and dynamic MRM mimic enable low‐ppb to ppt quantification.
• Retrospective analysis supports data review for new targets without re-analysis.
• Untargeted screening with multivariate statistics accelerates discovery of unknowns and transformation products.
• Versatile coupling (GC‐APCI, GC‐EI, LC‐ESI) addresses diverse polarity and volatility ranges.
• Powerful software tools streamline feature extraction, identification and statistical comparison.

Future Trends and Applications

Emerging directions include integration of machine learning for feature annotation, expansion of high‐mass libraries, real‐time monitoring with ambient ionization, miniaturized high‐resolution instruments for on-site analysis and coupling of ion mobility spectrometry for enhanced isomer separation. Data handling will evolve toward cloud-based retrospective mining and intelligent workflow automation.

Conclusion

High‐resolution GC/MS and LC/MS platforms deliver unparalleled capabilities for both targeted and untargeted analysis. Their combination of accurate mass, high sensitivity, rapid MS/MS and advanced data-mining software addresses regulatory requirements and research needs across environmental, food, petrochemical and natural product sectors.

References

No explicit literature references were provided in the original source.