Abstract:
A novel potentiometric and voltammetric sensor based on an ionophore (E)-3-(((2-((2 aminoethyl)amino)
ethyl)imino)methyl)-4H-chromen-4-one (ICU) has been developed for the detection of Cu(II). The
influence of variables including the amount of ionophore, plasticizers, anion excluder sodium
tetraphenylborate (NaTPB) and multiwalled carbon nanotubes (MWCNTs) on the performance of the
potentiometric sensor was studied. Under optimized conditions, the sensor has a wide linear range of
concentration (1.0 107
–1.0 101 mol L1
) and a low detection limit of 1.0 107 mol L1 for Cu(II)
ions with a stable response in a working pH range of 4.0–7.0. This electrode was also used as an
indicator electrode in the potentiometric titration of Cu(II) ions with EDTA. ICU is a promising molecule
with potential as a voltammetric sensor for Cu(II) species in DMSO medium in a concentration range of
2.5 106 mol L1 to 4.3 104 mol L1 and with a low detection limit of 9.3 109 mol L1
. Scanning
electron microscopy combined with energy dispersive X-ray spectra was used to confirm the interaction
between Cu(II) ions and the ionophore on the surface of the electrode. The proposed ionophore is
highly selective for Cu(II) ions over a number of metal ions. It was successfully applied for the
determination of Cu(II) ions in different real life samples from daily use items. Theoretical calculations
also support the complexation behavior of Cu(II) with ICU.
