Qualitative Analysis of Real Drug Evidence using DART-MS and the Inverted Library Search Algorithm

26 May 2022, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Chromatographic-less mass spectrometry techniques like direct analysis in real time mass spectrometry (DART-MS) are steadily being employed as seized drug screening tools. However, these newer analytical platforms require new computational methods to best make-use of the collected data. The inverted library search algorithm (ILSA) is a recently developed method designed specifically for working with mass spectra of mixtures collected with DART-MS, and has been implemented as a function in the NIST/NIJ DART-MS Data Interpretation Tool (DIT). This paper demonstrates how DART-MS and the ILSA/DIT can be used to analyze seized drug evidence, while discussing insights gathered during the evaluation of several adjudicated case samples. The evaluation verified that the combination of DART-MS and the ILSA/DIT can be used as an informative tool to help analysts screen seized drug evidence, but also revealed several factors an analyst must consider while employing these methods—all of these considerations are summarized in this paper.


Seized Drugs
Mass Spectrometry
Search Algorithms


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.