NEUTRAL CARRIER-BASED ION-SELECTIVE ELECTRODE WITH SIMILAR SENSITIVITY TO DIFFERENT MONOVALENT CATIONS AS A DETECTOR IN ION CHROMATOGRAPHY

A variety of neutral carrier-type ionophores were employed to prepare cation-selective electrodes for use as a detector in single-column ion chromatography. A polymer membrane electrode doped with a new siloxan e-based bis-crown ether exhibited similar selectivity to ammonium and all alkali metal ions except lithium. The lithium ion selectivity was induced by further incorporating an appropriate amount of lithium iono phore ETH 1810 into the bis-crown ether-doped membrane. A single-ionop hore membrane electrode doped with monensin-methyl ester, known as a s odium ionophore, was shown to exhibit the most comparable sensitivity towards all alkali metal ions and ammonium ion.