Zinc Selective Ionophores for Potentiometric and Optical Sensors

Abstract
Iminodiacetamide derivatives were synthesized and studied as ionophores in plasticized poly(vinyl chloride) membranes with potentiometric and optical transduction. The N-benzyl and N-phenyl derivatives proved to have a distinct zinc selectivity preferring Zn2+ over Ca2+, Na+ by factors of 6×105 and 3×104. respectively. All ionophores exhibit a serious proton interference (log KPot Zn ++, H + - 6) which suggests that all application of this type of ionophores based sensors are limited to hydrogen ion buffer solution at pH ≥ 6.