The Era of Mass SurveillanceIdentify Suspects, Confirm Targets and Explore Unknowns with GC/Q-TOF
Others, Presentations | 2018 | Agilent TechnologiesInstrumentation
Comprehensive chemical surveillance is essential in modern analytical chemistry to monitor known targets, screen large libraries of suspect compounds and uncover unexpected contaminants in complex matrices.
The study aims to showcase GC/Q-TOF technology as a panoramic tool for chemical surveillance, integrating targeted quantitation, suspect screening and unknown identification. Case studies focus on pesticide residues and environmental pollutants in food matrices.
Sample preparation involved QuEChERS extraction and dispersive SPE cleanup for various food matrices. Instrument configuration comprised an Agilent 7890B GC with mid-column backflush, dual HP-5ms UI columns and an MMI inlet. Detection was performed on an Agilent 7250 GC/Q-TOF operated at 70 eV and low energy modes (15 eV) with mass range 45-550 m/z and 5 spectra per second acquisition. Data processing utilized MassHunter software suite, SureMass signal processing and specialized Pesticide and Environmental Pollutants PCDL containing over 1000 curated compounds.
Targeted quantitation of hydroxylated PAH metabolites in urine and plasma exhibited linear calibration (R2 > 0.998), detection limits as low as 0.13 ng/mL and matrix RSD below 8.0%. Matrix-matched calibration across 2-500 ng/mL demonstrated robust performance for organochlorines, organophosphates, carbamates and pyrethroids. High mass accuracy (<1 ppm) enhanced confidence in peak identification and fragment confirmation according to EU SANTE guidelines. Suspect screening expanded the analytical scope to thousands of compounds with expert-curated spectral libraries. Untargeted analysis combined accurate mass and MS/MS fragmentation to elucidate unknowns, exemplified by identification of a trichloroisophthalonitrile degradation product of chlorothalonil.
The integrated GC/Q-TOF workflow enables simultaneous targeted, suspect and non-target screening, reducing run times and maximizing information from a single injection. It is suited for food safety monitoring, environmental surveillance, forensic toxicology and doping control where broad scope, high sensitivity and selectivity are required.
Advances are expected in expanding PCDL libraries, improving low energy EI for structural elucidation, refining data processing algorithms and integrating machine learning for non-target identification. Such developments will further enhance the ability to detect emerging contaminants in complex samples.
GC/Q-TOF mass spectrometry presents a panoramic technology for full spectrum chemical surveillance, uniting high resolution quantitation, extensive suspect library screening and unknown compound elucidation in a single platform.
MP 238 Analysis of polycyclic aromatic hydrocarbons (PAH) and hydroxylated PAH metabolites in plasma and urine
MP 284 Screening of contaminants in food and natural products
TP 180 Low Energy EI and High Resolving Power Instrumentation for the Analysis of Arson Samples
TP 213 Targeted and Untargeted Analysis of Pesticides and Other Contaminants in Fruits and Vegetables
WP 280 Analysis of doping and forensic drugs in urine
ThP 286 Analysis of halogenated polycyclic aromatic hydrocarbons in atmosphere
ThP 295 Combination of chemical ionization (CI) and low electron energy ionization capabilities
GC/MSD, GC/MS/MS, GC/HRMS, GC/Q-TOF
IndustriesManufacturerAgilent Technologies
Summary
Significance of the Topic
Comprehensive chemical surveillance is essential in modern analytical chemistry to monitor known targets, screen large libraries of suspect compounds and uncover unexpected contaminants in complex matrices.
Objectives and Study Overview
The study aims to showcase GC/Q-TOF technology as a panoramic tool for chemical surveillance, integrating targeted quantitation, suspect screening and unknown identification. Case studies focus on pesticide residues and environmental pollutants in food matrices.
Methodology and Instrumentation
Sample preparation involved QuEChERS extraction and dispersive SPE cleanup for various food matrices. Instrument configuration comprised an Agilent 7890B GC with mid-column backflush, dual HP-5ms UI columns and an MMI inlet. Detection was performed on an Agilent 7250 GC/Q-TOF operated at 70 eV and low energy modes (15 eV) with mass range 45-550 m/z and 5 spectra per second acquisition. Data processing utilized MassHunter software suite, SureMass signal processing and specialized Pesticide and Environmental Pollutants PCDL containing over 1000 curated compounds.
Main Results and Discussion
Targeted quantitation of hydroxylated PAH metabolites in urine and plasma exhibited linear calibration (R2 > 0.998), detection limits as low as 0.13 ng/mL and matrix RSD below 8.0%. Matrix-matched calibration across 2-500 ng/mL demonstrated robust performance for organochlorines, organophosphates, carbamates and pyrethroids. High mass accuracy (<1 ppm) enhanced confidence in peak identification and fragment confirmation according to EU SANTE guidelines. Suspect screening expanded the analytical scope to thousands of compounds with expert-curated spectral libraries. Untargeted analysis combined accurate mass and MS/MS fragmentation to elucidate unknowns, exemplified by identification of a trichloroisophthalonitrile degradation product of chlorothalonil.
Benefits and Practical Applications
The integrated GC/Q-TOF workflow enables simultaneous targeted, suspect and non-target screening, reducing run times and maximizing information from a single injection. It is suited for food safety monitoring, environmental surveillance, forensic toxicology and doping control where broad scope, high sensitivity and selectivity are required.
Future Trends and Potential Applications
Advances are expected in expanding PCDL libraries, improving low energy EI for structural elucidation, refining data processing algorithms and integrating machine learning for non-target identification. Such developments will further enhance the ability to detect emerging contaminants in complex samples.
Conclusion
GC/Q-TOF mass spectrometry presents a panoramic technology for full spectrum chemical surveillance, uniting high resolution quantitation, extensive suspect library screening and unknown compound elucidation in a single platform.
References
MP 238 Analysis of polycyclic aromatic hydrocarbons (PAH) and hydroxylated PAH metabolites in plasma and urine
MP 284 Screening of contaminants in food and natural products
TP 180 Low Energy EI and High Resolving Power Instrumentation for the Analysis of Arson Samples
TP 213 Targeted and Untargeted Analysis of Pesticides and Other Contaminants in Fruits and Vegetables
WP 280 Analysis of doping and forensic drugs in urine
ThP 286 Analysis of halogenated polycyclic aromatic hydrocarbons in atmosphere
ThP 295 Combination of chemical ionization (CI) and low electron energy ionization capabilities
Content was automatically generated from an orignal PDF document using AI and may contain inaccuracies.
Similar PDF
Screening of Contaminants in Food and Natural Products by GC/Q-TOF with an Accurate Mass Pesticides and Environmental Pollutants Library
2018|Agilent Technologies|Posters
Poster Reprint ASMS 2018 MP-284 Screening of Contaminants in Food and Natural Products by GC/Q-TOF with an Accurate Mass Pesticides and Environmental Pollutants Library Kai Chen and Courtney Milner Agilent Technologies, Inc., Santa Clara, CA Introduction Experimental Screening a broad…
Key words
library, libraryscreening, screeningdiff, diffmass, masscuration, curationdimethomorph, dimethomorphspectrum, spectrumcontaminants, contaminantstof, tofbroccoli, broccolipesticides, pesticidespollutants, pollutantsphthalate, phthalateaccurate, accuratefrag
Agilent 7250 GC/Q-TOF system
2019|Agilent Technologies|Brochures and specifications
Identify. Quantify. Simplify. See the Whole Picture Agilent 7250 GC/Q-TOF system Ready to Achieve More? Discovering what’s in your sample, at what levels, helps you make the conclusions and breakthroughs that your organization depends on. The all-in-one Agilent 7250 GC/Q-TOF…
Key words
masshunter, masshuntersoftware, softwaresuremass, suremassyou, youswarm, swarmunknowns, unknownscompound, compoundspectral, spectralsuspect, suspectagilent, agilentautotune, autotunelibrary, libraryionization, ionizationspectrum, spectrumchemical
Screening of Pesticides and Other Contaminants in Food Matrices Using a Novel High‑resolution GC/Q-TOF with a Low‑energy‑capable EI Source
2017|Agilent Technologies|Applications
Screening of Pesticides and Other Contaminants in Food Matrices Using a Novel High‑resolution GC/Q-TOF with a Low‑energy‑capable EI Source Application Brief Authors Introduction Kai Chen and Jennifer Sanderson The increasing demand of screening for contaminants in food requires an efficient…
Key words
qual, qualscreening, screeningonly, onlynonorganic, nonorganicbroccoli, broccolifood, foodcontaminants, contaminantscounts, countspesticides, pesticidesavocado, avocadountargeted, untargetedtbz, tbzresponses, responsesapple, applenicobifen
Accurately Identify Emerging Environmental Chemical Contaminants - Application Compendium
2018|Agilent Technologies|ApplicationsGuides
Find More, Miss Less Accurately Identify Emerging Environmental Chemical Contaminants Application Compendium Identify Emerging Contaminants in Air, Water, and Soil Today’s environmental analysis must be done more reliably, more efficiently, and with higher quality results than ever before. Unfortunately, pharmaceuticals,…
Key words
tof, tofmass, masscounts, countscompounds, compoundsaccurate, accuratewere, werescreening, screeningagilent, agilentusing, usingwater, waterpcdl, pcdlmasshunter, masshunterenvironmental, environmentalions, ionscompound
