Electrochemistry of 5F-MDMB-PICA synthetic cannabinoid using a boron-doped diamond electrode with short anodic-cathodic pretreatment: A simple screening method for application in forensic analysis

This work presents, for the first time, the electrochemical detection of methyl(2S)-2-{[1-(5-fluoropentyl)-1H-indole-3-carbonyl]amino}-3,3-dimethyl butanoate (5F-MDMB-PICA), which is one of the most reported syn-thetic cannabinoids (SCs) in seized forensic samples. The 5F-MDMB-PICA detection is based on adsorptive stripping differential pulse voltammetry (AdSDPV) using a boron-doped diamond electrode (BDDE) with short anodic-cathodic pretreatment. This SC exhibited an irreversible oxidation process at around +1.2 V on a BDDE (vs. Ag|AgCl|KCl(sat.)) in 0.1 mol L-1 H2SO4. The proposed method presents a wide linear range (1.0 to 100 mu mol L-1) for 5-MDMB-PICA determination and a low limit of detection (0.09 mu mol L-1). The selectivity for 5F-MDMB-PICA detection at the BDDE using AdSDPV was evaluated using six other SCs and no interference was observed. In addition, the BDDE showed a good stability of 5F-MDMB-PICA electrochemical responses. Addition-recovery studies in real seized samples presented results close to 100%. Therefore, the combination of BDDE with AdSDPV demonstrates a great potential for a simple and fast screening of 5F-MDMB-PICA and an on-site application in forensic analysis.