DART-MS

DART-MS implements a library-search algorithm to analyze DART-MS in-source collision-induced dissociation (CID) mass spectra and presumptively identify components of complex drug mixtures.

Key Features:

• Inverted Library-Search Algorithm (ILSA): A multistage search algorithm that enhances identification accuracy for mixture components by using staged spectral comparisons.
• Target peak selection: Searches for target peaks in the lowest-fragmentation mass spectrum and treats those peaks as protonated molecules for initial candidate selection.
• Scoring Mechanism: Scores each identified target peak against library entries to produce refined presumptive identifications.
• Database Compatibility: Operates with small custom libraries and larger resources such as the NIST DART-MS Forensics Database.
• Spectral input: Processes series of in-source collision-induced dissociation (CID) spectra acquired by DART-MS.
• Demonstrated mixtures: Demonstrated with model searches of mixtures containing acetyl fentanyl, benzyl fentanyl, amphetamine, and methamphetamine.

Scientific Applications:

• Forensic drug mixture identification: Presumptive identification of components in seized drug evidence using DART-MS spectra.
• Rapid presumptive screening: Supports rapid, initial-stage forensic screening of complex mixtures.
• Research method development: Provides a framework for extending and evaluating DART-MS mixture analysis methods in research studies.

Methodology:

Acquire a series of in-source CID mass spectra using DART-MS; the ILSA performs a multistage search by finding target peaks in the lowest-fragmentation spectrum (assumed protonated molecules) and scoring those targets against library spectra.