Abstract
The first asymmetric potentiometric UO2(II) microsensor is introduced. 5,11,17,23-tetra-tertio butyl(25,27),-bis)2-)n-]2-hydroxy-5-dinitridphenilonitrilidine) amino etoxy(26,28)-di hydroxy calix[4]arene (HAECA) was synthesized. It was found that HAECA can be used as an excellent ionophore in construction of UO2(II) microsensor. The best performance was obtained with a membrane composition containing 20% PVC, 73% dibutyl phthalate, 5% HAECA, and 2% sodium tetraphenyl borate. The proposed microsensor exhibits a Nernstian slope of 28.5 ± 0.3 mV per decade over a wide concentration range of 1.0 ×10−10–1.0 × 10−4 M and a detection limit of 6.0 × 10−11 M. The potentiometric response of the sensor is independent to the pH of the solution in the range of 2.2–3.6.
The authors express their appreciation to the University of Tehran Research Council for financial support of this work.