Potassium ion-selective membrane electrodes based on 1,3-alternate calix[4]crown-5-azacrown-5.
A series of 1,3-alternate calix[4]azacrown ethers for which the monoaza and unsymmetrical crowned-azacrown with different side arms were examined as an ionophore for ion-selective polymeric membrane electrode toward potassium ion. Among them, the electrode based on calix[4]crown-5-azacrown-5 with a phenyl group exhibited near Nernstian response for K(+) ions over a wide concentration range (1x10(-5) to 1x10(-1) M) with a limit of detection of 2x10(-6) M. It has a fast response time of approximately 2-3 s and can be used for at least 2 months without observing any major deterioration. Selectivity coefficients indicated that interference from all common alkali, alkaline and transition metal ions was very small.
Kim
Sungeun
S
School of Chemistry and Molecular Engineering, Center for Molecular Catalysis, Seoul National University, Seoul 151-742, South Korea.
Kim
Hasuck
H
Noh
Kwan Ho
KH
Lee
Seoung Ho
SH
Kim
Sung Kuk
SK
Kim
Jong Seung
JS