Feasibility study of ethylone determination in seized samples using boron-doped diamond electrode associated with solid phase extraction

• Published in: Sensors and actuators. B, Chemical Vol. 259; pp. 1113 - 1122
• Main Authors: Scheel, Guilherme Luiz, de Oliveira, Fernanda Midori, de Oliveira, Leandro Luan Gonçalves, Medeiros, Roberta Antigo, Nascentes, Clésia Cristina, Tarley, César Ricardo Teixeira
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.04.2018; Elsevier Science Ltd
• Subjects: Adulterants; BDD electrode; Boron; Caffeine; Central nervous system; Diamond tools; Diamonds; Drugs; Ecstasy; Electrochemical analysis; Electrochemistry; Electrodes; Ethylone; Feasibility studies; Illicit drugs; Oxidation; Seizing; Silicon dioxide; Voltammetry; Ecstasy; Electrochemistry; Illicit drugs; Ethylone; BDD electrode
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.12.129

[Display omitted] •For the first time a voltammetric method has been reported for ethylone determination in seized street drugs.•The boron-doped diamond (BDD) electrode fouling was not observed and common adulterants did not exert interference on ethylone determination.•The association of boron-doped diamond (BDD) electrode with solid-phase extraction (SPE) was very useful to overcome the caffeine interference. Ethylone is a synthetic cathinone recently found in illicit drugs, due to its similar central nervous system-stimulation properties with ‘ecstasy’. Due to the necessity of a rapid and routine on-site determination of ethylone in illicit drugs, electrochemical techniques seem to be an advantageous analytical tool. In this report, a novel voltammetric method using a boron-doped diamond electrode to determinate ethylone was developed and applied in seized street drugs. Electrochemical behavior of ethylone was studied by cyclic, differential pulse (DPV) and square-wave voltammetry (SWV). Chemometric approach was applied for determining ethylone by DPV and SWV. Validation parameters, such as linear range, limit of quantification and detection, precision and accuracy, were evaluated by SWV. Adulterants typically found in seized street drugs were also evaluated as possible interfering compounds. It was observed that oxidation peaks of ethylone and caffeine overlapped, whose interference was further overcome by previous solid phase extraction with octadecyl silica (C18) as sorbent to eliminate the interfering effect of caffeine. The developed method was applied in seized samples and the accuracy was attested by comparison with HPLC-DAD. The results found using the developed electroanalytical methodology enabled to gather some information about the content and amount of ethylone present in seized street drugs found in Brazil.