The relationship between the selectivity of six drug ion-selective electrodes with anionic species of hetero-poly acid as exchange site and the structural and thermodynamical parameters of the metal ion has been inves...The relationship between the selectivity of six drug ion-selective electrodes with anionic species of hetero-poly acid as exchange site and the structural and thermodynamical parameters of the metal ion has been investigated experimentally and theoretically. The electrode selectivity is controlled mainly by the extractibility or hydrophobicity of the metal ion, but not by the ion-association-complex formation process. Linear relationship exists between the pK_(ij) value and the structural parameter z^2/(r + 0.85) and the thermodynamic parameter of hydration (△G_h) of the metal ion. Better correlation is obtained for the pK_(ij)vs. (z^2/r)^(-k) relationship.展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘The relationship between the selectivity of six drug ion-selective electrodes with anionic species of hetero-poly acid as exchange site and the structural and thermodynamical parameters of the metal ion has been investigated experimentally and theoretically. The electrode selectivity is controlled mainly by the extractibility or hydrophobicity of the metal ion, but not by the ion-association-complex formation process. Linear relationship exists between the pK_(ij) value and the structural parameter z^2/(r + 0.85) and the thermodynamic parameter of hydration (△G_h) of the metal ion. Better correlation is obtained for the pK_(ij)vs. (z^2/r)^(-k) relationship.