An electrochemical sensor for the determination of Cu(II) using a modified electrode with ferrocenyl crown ether compound by square wave anodic stripping voltammetry

An electrochemical sensor based on a glassy carbon electrode modified with ferrocenyl imine [(eta(5)-C5H4CH=N-4'-benzo-15-crown-5)Fe(eta(5)-C5H5)] (FcIB15C5) has been developed for the determination of Cu(II) using square wave anodic stripping voltammetry (SWASV). The metalloligand was synthesized from ferrocene-carboxaldehyde and 4'-aminobenzo-15-crown-5. The metalloligand FcIB15C5 was characterized by FT-IR, H-1 - C-13 NMR spectroscopies and mass spectrometry and was obtained as a single isolated isomer (E-configuration). The optimum conditions for the prepared electrode were as follows: BrittonRobinson buffer with pH = 6.0, FcIB15C5 concentration = 0.3 mM, accumulation potential (E-acc) = -0.8 V and accumulation time (t(acc)) = 90 s. A linear range was observed from 10 to 70 mu g L-1 with a limit of detection (LOD) of 0.11 mu g L-1. The proposed procedure was validated with TMDA-64.2 and CRM-TMDW certified reference materials, and it showed good accuracy and precision. The methodology was applied to a mining effluent and urine samples with satisfactory results. (C) 2017 Elsevier B.V. All rights reserved.