Rapid identification of seized controlled substances and related compounds by tandem mass spectrometry without chromatography

Rapid Commun Mass Spectrom. 2016 Apr 15;30(7):908-16. doi: 10.1002/rcm.7514.

Abstract

Rationale: This study demonstrates the capability of using tandem mass spectrometry (MS/MS) for the identification of substances of abuse and related compounds without the need for chromatography. The elimination of chromatography is not only cost-effective because of reduced sample work-up and consumables, but also reduces the environmental impact of solvents.

Methods: Two chromatography-free techniques were used to screen for a large suite of compounds using a rapid, inexpensive technique: a thermal desorber coupled to a tandem mass spectrometer operated in selected reaction monitoring (SRM) mode. First, questioned materials in solution were introduced via an autosampler; and secondly, the materials were introduced directly by means of disposable toothpicks. The results were compared with those obtained by gas chromatography/mass spectrometry (GC/MS).

Results: MS/MS was shown to be capable of the identification of the same drugs within the samples as the conventional method of GC/MS, but with better sensitivity and shorter analysis times. Presented herein is an automated screening method based on an algorithm containing more than 60 precursor ion/product ion 'transitions' (i.e. 30+ compounds simultaneously; two precursor/product ion transitions per analyte), requiring less than 2 min for identification using an autosampler or instantaneously by means of manual sample introduction. Therefore, by eliminating chromatography, a higher laboratory throughput is achievable with simplified sample preparation.

Conclusions: An inexpensive, rapid and reliable method was successfully developed for the identification of controlled substances within unknown matrices using MS/MS without any chromatographic separation. This technique could be further validated with reference to an increasing database of MS/MS spectra to help to identify an expanding suite of compounds. Copyright © 2016 John Wiley & Sons, Ltd.