TY - JOUR

T1 - Infrared and Raman screening of seized novel psychoactive substances

T2 - a large scale study of >200 samples

AU - Jones, Louise E.

AU - Stewart, A.

AU - Peters, K. Laota

AU - McNaul, M.

AU - Speers, S. James

AU - Fletcher, Nicholas Charles

AU - Bell, Steven E. J.

N1 - This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. This journal is © The Royal Society of Chemistry 2016

PY - 2016/2/7

Y1 - 2016/2/7

N2 - The potential of IR absorption and Raman spectroscopy for rapid identification of novel psychoactive sub- stances (NPS) has been tested using a set of 221 unsorted seized samples suspected of containing NPS. Both IR and Raman spectra showed large variation between the different sub-classifications of NPS and smaller, but still distinguishable, differences between closely related compounds within the same class. In initial tests, screening the samples using spectral searching against a limited reference library allowed only 41% of the samples to be fully identified. The limiting factor in the identification was the large number of active compounds in the seized samples for which no reference vibrational data were available in the libraries rather than poor spectral quality. Therefore, when 33 of these compounds were independently identified by NMR and mass spectrometry and their spectra used to extend the libraries, the percentage of samples identified by IR and Raman screening alone increased to 76%, with only 7% of samples having no identifiable constituents. This study, which is the largest of its type ever carried out, therefore demon- strates that this approach of detecting non-matching samples and then identifying them using standard analytical methods has considerable potential in NPS screening since it allows rapid identification of the constituents of the majority of street quality samples. Only one complete feedback cycle was carried out in this study but there is clearly the potential to carry out continuous identification/updating when this system is used in operational settings.

AB - The potential of IR absorption and Raman spectroscopy for rapid identification of novel psychoactive sub- stances (NPS) has been tested using a set of 221 unsorted seized samples suspected of containing NPS. Both IR and Raman spectra showed large variation between the different sub-classifications of NPS and smaller, but still distinguishable, differences between closely related compounds within the same class. In initial tests, screening the samples using spectral searching against a limited reference library allowed only 41% of the samples to be fully identified. The limiting factor in the identification was the large number of active compounds in the seized samples for which no reference vibrational data were available in the libraries rather than poor spectral quality. Therefore, when 33 of these compounds were independently identified by NMR and mass spectrometry and their spectra used to extend the libraries, the percentage of samples identified by IR and Raman screening alone increased to 76%, with only 7% of samples having no identifiable constituents. This study, which is the largest of its type ever carried out, therefore demon- strates that this approach of detecting non-matching samples and then identifying them using standard analytical methods has considerable potential in NPS screening since it allows rapid identification of the constituents of the majority of street quality samples. Only one complete feedback cycle was carried out in this study but there is clearly the potential to carry out continuous identification/updating when this system is used in operational settings.

U2 - 10.1039/C5AN02326B

DO - 10.1039/C5AN02326B

M3 - Journal article

VL - 141

SP - 902

EP - 909

JO - Analyst

JF - Analyst

SN - 0003-2654

IS - 3

ER -