These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
asm-ILSA_v1.pdf (797.66 kB)

A New Library-Search Algorithm for Mixture Analysis Using DART-MS

submitted on 11.03.2021, 17:01 and posted on 16.03.2021, 10:03 by Arun Moorthy, Edward Sisco
This manuscript introduces a new library-search algorithm for identifying components of a mixture using in-source collision-induced dissociation (is-CID) mass spectra. The two-stage search, titled the Inverted Library-Search Algorithm (ILSA), identifies potential components in a mixture by first searching its low fragmentation mass spectrum for target peaks, assuming these peaks are protonated molecules, and then scoring each target peak with possible library matches using one of two schemes. Utility of the ILSA is demonstrated through several example searches of model mixtures of acetyl fentanyl, benzyl fentanyl, amphetamine and methamphetamine searched against a small library of select compounds and the NIST DART-MS Forensics library. Discussion of the search results and several open areas of research to further extend the method are provided. A prototype implementation of the ILSA is available at


Email Address of Submitting Author


National Institute of Standards and Technology



ORCID For Submitting Author


Declaration of Conflict of Interest

No conflicts of interest

Version Notes

Preliminary draft.