Synthetic cannabinoid receptor agonists (Spice): the problem they represent and a chemometric solution

Abstract

Synthetic cannabinoid receptor agonists (SCRAs) are novel psychoactive substances (NPS) that can bind to and trigger endogenous cannabinoid receptors, initially developed as research agents for studying the endocannabinoid system and later for therapeutic purposes. Significant side effects limited their use as therapeutics, but SCRAs were sold to members of the public in the UK as “legal highs” in the early 2000s. Despite the known adverse effects and implemented legislation changes, SCRAs remain in circulation, particularly amongst vulnerable populations, as the sheer diversity of SCRA chemical structures makes it difficult to detect SCRAs in an adulterated product such as tobacco. To overcome this issue, researchers have looked at multivariate techniques such as Raman and near-infrared spectroscopy in combination with chemometric techniques including principal component analysis and partial least-squares regression to detect the diverse range of SCRAs. This review discusses the problem that SCRAs represent, and then the analytical and chemometric techniques that can/could be brought to bear on said problem.