preprints.org > chemistry > analytical chemistry > doi: 10.20944/preprints202202.0300.v1

Preprint Article Version 1 Preserved in Portico This version is not peer-reviewed

Version 1 : Received: 22 February 2022 / Approved: 24 February 2022 / Online: 24 February 2022 (04:00:15 CET)

Illicit drug consumption is posing critical concerns in our society causing health issues, crime-related activities, and the disruption of border trade. The smuggling of illicit drugs urges the development of new tools for rapid on-site identification in cargos. Current methods used by law enforcement officers rely on presumptive color tests and portable spectroscopic techniques. However, these methods sometimes exhibit inaccurate results due to commonly used cutting agents, the colorful nature of the sample or because the drugs are smuggled (hidden or mixed) in common goods. Interestingly, electrochemical sensors can deal with these specific problems. Herein, an electrochemical device is presented that uses affordable screen-printed electrodes for the electrochemical profiling of illicit drugs by square-wave voltammetry (SWV). The identification of the illicit compound is based on the oxidation potential of the analyte. Hence, a library of electrochemical profiles is built upon the analysis of illicit drugs and common cutting agents. This library allows the design of a tailor-made script that enables the identification of each drug through a user-friendly interface (laptop or mobile phone). Importantly, the electrochemical test is compared by analyzing 48 confiscated samples with other portable devices based on Raman and FTIR spectroscopy as well as a laboratory standard method (i.e. gas chromatography – mass spectrometry). Overall, the electrochemical results obtained through the analysis of different samples from confiscated cargos at an end-user site, present a promising alternative to current methods, offering low-cost and rapid testing in the field.

Electrochemical sensors; square-wave voltammetry; screen-printed electrodes; electrochemical profiling; illicit drugs; forensic analysis; Raman spectrometer; on-site detection; FTIR spectrometer

CHEMISTRY, Analytical Chemistry