Synthesis and Electrochemical Behavior of a New Water Soluble Ca2+-selective Ionophore
Based on Calix[4]arene-triacid-monoquinone
Taek Dong Chung,? �#060;/SUP> Sun Kil Kang, Hasuck Kim,* Joo Ryun Kim,??#060;/SUP> Weon Seok Oh,??#060;/SUP> and Suk-Kyu Chang*??#060;/P>
Department of Chemistry and Center for Molecular Catalysis, Seoul National University, Seoul 151-742, Korea ??#060;/SUP>Department of Chemistry, Chung-Ang University, Seoul 156-756, Korea ? �#060;/SUP>Institute of Medical and Biological Engineering, Medical Research Center, Seoul National University, Seoul 110-799, Korea (Received July 31 1998) A new water-soluble calix[4]arene-triacid-monoquinone 3 has been synthesized and its ion binding properties in aqueous solution were investigated by means of voltammetry and UV-visible spectrophotometry. The electrochemical behavior of 3 is dependent on the concentration of Ca2+ ion rather than that of other alkaline earth metal ions as well as alkali metal cations. The selective response toward Ca2+ was achieved even in the presence of a large excess (> 1000-fold) of interfering Na+ ion.