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Large Scale Non-targeted Metabolomic Profiling of Serum by Ultra Performance Liquid Chromatography-Mass Spectrometry UPLC-MS
Published on: March 14, 2013
High-Resolution Mass Spectrometry for Untargeted Drug Screening.
1Department of Laboratory Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA, USA. wualan@labmed2.ucsf.edu.
High-resolution mass spectrometry (HR-MS) enhances clinical toxicology by enabling presumptive identification of unknown drugs and metabolites without library matching. This advanced technique expands detection capabilities for comprehensive patient care.
Area of Science:
- Analytical Chemistry
- Forensic Toxicology
- Clinical Chemistry
Background:
- Gas chromatography-mass spectrometry (GC/MS) is the forensic standard for toxicology.
- Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) offers advantages for targeted analysis.
- LC-high-resolution mass spectrometry (LC-HR-MS) is emerging for untargeted analysis.
Purpose of the Study:
- To evaluate the utility of LC-HR-MS in clinical toxicology.
- To explore the advantages of HR-MS for presumptive identification of unknowns.
- To expand the scope of detectable drugs and metabolites.
Main Methods:
- Utilized HR-MS analyzers (Orbitrap, time-of-flight MS) with soft ionization.
- Achieved 1 ppm mass resolution for accurate molecular formula assignment.
- Performed untargeted analysis for presumptive identification without library matching.
Main Results:
- HR-MS enables presumptive identification of unknowns by assigning exact molecular formulas.
- This approach limits the number of candidate compounds.
- Expanded the range of detectable drugs and metabolites on a presumptive basis.
Conclusions:
- LC-HR-MS offers significant advantages for untargeted analysis in clinical toxicology.
- Presumptive identification is achievable without MS library spectra or known standards.
- Definitive identification can be confirmed retrospectively with reference standards.
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