SODIUM-SELECTIVE POLYMERIC MEMBRANE ELECTRODES BASED ON CALIX[4]ARENE DERIVATIVES

Four kinds of lipophilic calix[4]aryl ester derivatives (A)-(D) have been designed for Na+-selective polymeric membrane electrodes. On the ion selectivity of (A)-based electrode, the phenyl ether type membrane solvent, especially FPNPE is superior to the diester type ones in Na+ selectivity against K+. On the contrary, in the Na+ electrode of (B), de-tert-butylated derivative of (A), the diester type solvent, DOP gave good result.,The selectivity coefficients for Na+ with respect to K+ (-log k(Nak)(Pot)) being nearly 2.5. The (B)/DOP-based Na+-selective electrode was successfully applied to Na+ assay in human blood sera.