Prototype test to detect ‘spice’ drug in saliva

Scientists at the University of Bath (UK) have developed a prototype test that could detect if an individual has recently taken the street drug ‘spice’ in under 5 minutes by analyzing a saliva sample. With further successful development, the test could be used by healthcare professionals to rapidly identify and appropriately treat individuals suffering from the effects of ‘spice’.

‘Spice’ is the street name for synthetic cannabinoid receptor agonists (SCRAs). SCRAs are highly potent and addictive and have gained popularity over the past decade. Traditionally detecting SCRAs has proved challenging due to their structural and chemical diversity.

Detection and chemical identification of SCRAs invariably requires GC–MS, which is not plausible in most situations where rapid detection is critical, including hospitals, prisons and amongst homeless communities.

In the team’s proof-of-concept study, published in Analytical Chemistry, the use of fluorescence spectral fingerprinting to identify the likely presence of SCRAs is described. The team report that the fluorescence spectral fingerprints of SCRAs are unique owing to a number of factors, including: solvent effects, substituent effects, conjugation between chromophores and fluorescence resonance energy transfer between chromophores.

Using fluorescence data, the team explained that SCRA concentration can be inferred from the intensity of emission at a specific wavelength on the basis of a known calibration curve. The research demonstrated that using combined excitation/emission matrices, the prototype test could accurately discern SCRAs against a complex biological background such as saliva.

The researchers hope to further optimize their prototype test for use within a clinical setting. Lead author Christopher Pudney (University of Bath) concluded: “We’ve proved the concept with a test that’s simple and very accurate. The hardware is compact and portable and the results are easy to understand. We’re working on software now, so that the user has a simple ‘one click’ way to use it.”

Sources: May B, Naqi HA, Tipping M et al. Synthetic cannabinoid receptor agonists detection using fluorescence spectral fingerprinting. Anal. Chem. 91(20), 12971–12979 (2019); www.bath.ac.uk/announcements/world-first-on-the-spot-test-for-synthetic-drug-spice-developed-at-university-of-bath/