Fentanyl quantification using portable infrared absorption spectroscopy. A framework for community drug checking

Abstract

Abstract Infrared absorption spectroscopy has been used as part of a multi-technology approach implemented in a community drug checking project in Victoria, BC, Canada. As most synthetic opioids are either binary mixtures of fentanyl and caffeine, or ternary mixtures of fentanyl with caffeine and a sugar alcohol, standards consisting of such mixtures have been prepared and were used to train a partial least squares regression model to quantify the fentanyl concentration in the mixture. Extensive details of the spectral pre-processing, and model development are provided. The model was then used to evaluate the fentanyl concentration of samples brought to the service by people who use drugs. This demonstrates that portable infrared absorption spectroscopy can be used not only to identify components in drug mixtures, but also to determine concentrations of fentanyl in complex mixtures as seen in illicit opioids.