IDSL.UFA

IDSL.UFA annotates molecular formulas for untargeted liquid chromatography/high-resolution mass spectrometry (LC/HRMS) peaks to support metabolomics and exposomics analyses by matching theoretical isotopic profiles and incorporating tandem mass spectrometry information.

Key Features:

• Molecular Formula Assignment: Assigns molecular formulas to LC/HRMS peaks by matching theoretical isotopic profiles (MS1) of ionized compounds with observed data.
• Validation and Accuracy: Demonstrated assignment of molecular formulas to 54.31-85.51% of true positive annotations as the top hit and 90.58-100% within the top five hits in untargeted metabolomics validation tests.
• Integration with Tandem Mass Spectrometry: Supports molecular formula annotations using tandem mass spectrometry (MS/MS) data for additional validation.
• Formula Source Generation: Generates formula sources and their theoretical isotopic profiles to improve assignment accuracy.
• Optimized Formula Hits Ranking: Optimizes ranking of formula hits for both individual and aligned peak lists to enhance identification precision.
• Scalability: Designed to handle studies with larger sample sizes for large-scale analyses.

Scientific Applications:

• Human metabolomics and exposomics: Provides high-confidence molecular formula annotations for untargeted LC/HRMS biospecimen analyses to preserve biological insights.
• Pregnancy metabolome discovery: Applied to a publicly available pregnancy metabolome study to annotate raw data and uncover hundreds of new pregnancy-related compounds.
• Exposomics detection: Enabled identification of chlorinated perfluorotriether alcohols (Cl-PFTrEAs) in human specimens.

Methodology:

Matches observed MS1 isotopic profiles to generated theoretical isotopic profiles from formula sources, supports MS/MS-based annotation, and optimizes ranking of formula hits for individual and aligned peak lists.