Screening and Confirmation of Seized Drugs Utilizing Portable Raman Spectroscopy (TacticID) and Direct Analysis in Real Time-Mass Spectrometry (DART-MS)
Travon Cooman, Colby E. Ott, Kourtney A. Dalzell, Amber Burns, Edward Sisco, Luis E. Arroyo
The continuous change of the drug landscape in the United States demands adaptation and incorporation of emerging analytical methods that preferably allow onsite screening but are also capable of supporting the analysis of seized drugs received at forensic laboratories across the country. Current methods employing color testing require the interaction of chemical reagents with powdered and liquid materials and can often yield inconclusive results, especially when the material is impure. Implementation of portable Raman spectroscopy can remove the need for direct interaction with solid and liquid specimens. In this study, we assessed the ability of a portable, 785 nm, Raman spectroscopy system for identification of seized drug samples, including mixtures. The system was first validated for use using a panel of analytes comprised of 15 common drugs of abuse, 15 diluents, and 64 different mixtures comprising various ratios of analytes. Bias, precision, and repeatability were then established according to the UNODC guidelines on handheld Raman field identification devices for seized material. Accuracy and precision through glass packaging was 91% and 90%; and through plastic was 89% and 88%, respectively. The same pure and mixture samples were then assessed using direct analysis in real time mass spectrometry (DART-MS). Identification of analytes was performed manually by observing the [M+H]+ protonated molecule and through library search of an in-house database. Using DART-MS, the drug analyte present in the sample was correctly identified 93 % of the time using the library search feature. The presence of dimers and –OH losses were also observed for many of the analyte drugs of abuse. The combination of portable Raman spectroscopy and DART-MS data resulted in an overall accuracy of 96 % for in-house binary mixtures and ≥96 % for the detection of target drugs and diluents. The combined accuracy when analyzing authentic case samples was 93 %, providing a rapid and accurate method for seized drug identification within drug chemistry laboratories.
, Ott, C.
, Dalzell, K.
, Burns, A.
, Sisco, E.
and Arroyo, L.
Screening and Confirmation of Seized Drugs Utilizing Portable Raman Spectroscopy (TacticID) and Direct Analysis in Real Time-Mass Spectrometry (DART-MS), Forensic Chemistry, [online], https://doi.org/10.1016/j.forc.2021.100352, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=932328
(Accessed February 3, 2023)