Lai Chun-Ze, Joyer Marti M, Fierke Melissa A, Petkovich Nicholas D, Stein Andreas, Bühlmann Philippe
Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota, 55455.
J Solid State Electrochem. 2009 Jan 1;13(1):123-128. doi: 10.1007/s10008-008-0579-2.
Solid-contact ion-selective electrodes (SC-ISEs) can exhibit very low detection limits and, in contrast to conventional ISEs, do not require an optimization of the inner filling solution. This work shows that subnanomolar detection limits can also be achieved with SC-ISEs with three-dimensionally ordered macroporous (3DOM) carbon contacts, which have been shown recently to exhibit excellent long-term stabilities and good resistance to the interferences from oxygen and light. The detection limit of 3DOM carbon-contacted electrodes with plasticized poly(vinyl chloride) as membrane matrix can be improved with a high polymer content of the sensing membrane, a large ratio of ionophore and ionic sites, and conditioning with a low concentration of analyte ions. This permits detection limits as low as 1.6×10(-7) M for K(+) and 4.0×10(-11) M for Ag(+).
固态接触式离子选择电极（SC-ISEs）能够呈现出极低的检测限，并且与传统离子选择电极不同的是，它不需要对内充溶液进行优化。这项工作表明，具有三维有序大孔（3DOM）碳接触的SC-ISEs也能够实现亚纳摩尔级的检测限，最近已证明这种电极具有出色的长期稳定性以及对氧气和光干扰的良好抗性。以增塑聚氯乙烯为膜基质的3DOM碳接触电极的检测限，可通过传感膜的高聚合物含量、离子载体与离子位点的大比例以及用低浓度分析物离子进行预处理来提高。这使得钾离子（K(+)）的检测限低至1.6×10(-7) M，银离子（Ag(+)）的检测限低至4.0×10(-11) M。
