Taek Dong CHUNG*, Suk-Kyu CHANG**, Jongseo PARK and Hasuck
KIM
Department of Chemistry and Center for Molecular Catalysis,
Seoul National University, Seoul 151-742, KOREA
*Institute of Biomedical Engineering, Seoul National University, Seoul 110-744, KOREA
**Department of Chemistry, Chung-Ang University, Seoul 156-756, KOREA
Bis(15-crown-5 ether) derivatized from a xanthene-4,5-dicarboxylic acid
skeleton was studied as an ionophore for a new K+-selective electrode.
The polymeric liquid membrane based on this ionophore exhibits
Nernstian behavior and optimization of experimental conditions for
potentiometric analysis offers a wide linear dynamic range, reasonable
detection limit, good durability and hysteresis within a limited error.
Due to the well-preorganizedstructure, the selectivity over Na+ is
comparable to those of commercialized K+-selectiveionophores and
the interferences by some cations such as Rb+ and Cs+ are reduced.
Except slightly slow response, the enhanced recognition ability is
reminiscent of the naturalantibiotic valinomycin.
Keywords Bis(15-crown-5 ether), potassium ion-selective electrode,
potentiometric analysis