Development of Ion sensor for Transition Metal Ion with Porphyrin Derivatives

电位离子传感器，如离子选择电极（ISEs）是非常有吸引力的装置，用于测量溶液的浓度。离子的选择性很大程度上取决于离子载体的性质。影响离子感测的主要因素是配位原子的类型、适合于目的离子的空穴大小和亲脂性。由于过渡金属的离子半径非常接近，因此判别过渡金属离子非常困难。然而，基于上述概念的分子设计并不能解决这一问题。我们注意到卟啉衍生物具有各种生物分子的基本框架。实际上，卟啉衍生物与液晶，5,10,15,20-四苯基卟啉是重点。在过渡金属离子中，基于该卟啉的电极对Ag+离子表现出较高的选择性。

Potentiometric ion sensors such as ion-selective electrodes (ISEs) are very attractive devices for the measurement of the concentration of solutions. The ion selectivities are greatly governed by the properties of ionophores. The main factors which influence the ion sensing are the type of the coordination atom, the hole size suitable for the purpose ion, and the lipophilicity. The discrimination of transition metal ion is very difficult, because ionic radius of transition metal is similar to each other. However, the molecular design based on above concept can not solve this problem. We noticed porphyrin derivatives with the basic framework of various biomolecules. Actually, the porphyrin derivative with the liquid crystal, 5,10,15,20-tetraphenylporphyrin was focused. Among of the transition metal ions, the electrode based on this porphyrin showed the high selectivity for Ag+ ion.