Single-Piece Solid Contact Cu(2+)-Selective Electrodes Based on a Synthesized Macrocyclic Calix[4]arene Derivative as a Neutral Carrier Ionophore

Herein, a facile route leading to good single-walled carbon nanotubes (SWCNT) dispersion or poly (3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) based single-piece nanocomposite membrane is proposed for trace determination of Cu(2+) ions. The single-piece solid contact Cu(2+)-selective electrodes were prepared after drop casting the membrane mixture on the glassy-carbon substrates. The prepared potentiometric sensors revealed a Nernstian response slope of 27.8 ± 0.3 and 28.1 ± 0.4 mV/decade over the linearity range 1.0 × 10(−3) to 2.0 × 10(−9) and 1.0 × 10(−3) to 1.0 × 10(−9) M with detection limits of 5.4 × 10(−10) and 5.0 × 10(−10) M for sensors based on SWCNTs and PEDOT/PSS, respectively. Excellent long-term potential stability and high hydrophobicity of the nanocomposite membrane are recorded for the prepared sensors due to the inherent high capacitance of SWCNT used as a solid contact material. The sensors exhibited high selectivity for Cu(2+) ions at pH 4.5 over other common ions. The sensors were applied for Cu(2+) assessment in tap water and different tea samples. The proposed sensors were robust, reliable and considered as appealing sensors for copper (II) detection in different complex matrices.