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

Abstract

An electrochemical sensor based on a glassy carbon electrode modified with ferrocenyl imine [(η5-C5H4CH=N-4′-benzo-15-crown-5)Fe(η5-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, 1H - 13C 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: Britton–Robinson buffer with pH=6.0, FcIB15C5 concentration=0.3mM, accumulation potential (Eacc)=−0.8V and accumulation time (tacc)=90s. A linear range was observed from 10 to 70μgL−1 with a limit of detection (LOD) of 0.11μgL−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.