IDSL CSA

IDSL CSA generates composite mass spectra libraries from MS1-only high-resolution mass spectrometry data coupled to liquid or gas chromatography to enable chemical annotation in untargeted metabolomics and exposomics.

Key Features:

• Composite spectra generation: Creates composite mass spectra libraries exclusively from MS1-only data to represent chromatographic peaks without requiring MS2 fragmentation spectra.
• MS1-based library search: Enables searches for liquid chromatography peaks using MS1-derived composite spectra instead of MS2 spectra.
• High-resolution MS support: Operates on datasets generated by high-resolution mass spectrometry coupled to liquid chromatography or gas chromatography.
• Validation on human samples: Demonstrated comparable annotation rates for commonly detected endogenous metabolites in validation tests using human blood samples.
• Implementation: Provided as an R package (IDSL.CSA) for computational integration into data analysis workflows.

Scientific Applications:

• Chemical annotation in untargeted metabolomics: Supports metabolite identification when MS2 fragmentation data are unavailable or incomplete.
• Exposomics studies: Facilitates annotation of exogenous and endogenous compounds in exposomics datasets derived from LC- or GC-coupled high-resolution MS.
• Cross-study spectral library use: Enables creation and reuse of composite spectra libraries across different untargeted metabolomics datasets and instrument setups.
• Biological validation: Applicable to annotation and discovery efforts in human blood metabolomics as demonstrated in validation tests.

Methodology:

Generates composite mass spectra libraries from MS1-only high-resolution mass spectrometry data and performs MS1-based library searches for liquid chromatography peaks; implemented as an R package (IDSL.CSA).