Bakker Eric, Pretsch Ernö
Auburn University, USA.
Anal Chem. 2002 Aug 1;74(15):420A-426A. doi: 10.1021/ac022086f.
During the last decade, the capabilities of potentiometric analysis have changed fundamentally in that the lower limit of detection (LOD) of ion-selective electrodes (ISEs) has improved by a factor of up to one million and the discrimination factor of interferences from ions by up to one billion. These spectacular improvements are related to the control of ion fluxes through the ion-selective membrane. Nowadays, ISEs can be used for trace measurements in environmental samples. However, by reducing the volume of the samples, the LOD in terms of the amount of analytes has been reduced to the attomole range. This is promising for bioanalysis using metal nanoparticle labels. Other recent progress includes the excellent fundamental understanding of the working mechanism, the introduction of a novel kind of calibration procedure that reduces the demands on signal stability and reproducibility, and the advent of pulsed amperometric methods.
在过去十年中，电位分析的能力发生了根本性变化，离子选择性电极（ISE）的检测下限（LOD）提高了高达一百万倍，对离子干扰的区分因子提高了高达十亿倍。这些显著的改进与通过离子选择性膜控制离子通量有关。如今，ISE可用于环境样品中的痕量测量。然而，通过减少样品体积，以分析物量计的LOD已降至阿托摩尔范围。这对于使用金属纳米颗粒标记物的生物分析很有前景。最近的其他进展包括对工作机制有了出色的基本理解、引入了一种新型校准程序，该程序降低了对信号稳定性和重现性的要求，以及脉冲安培法的出现。
