Kazemi Sayed Habib, Shanehsaz Maryam, Ghaemmaghami Mostafa
Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran.
Analytical Chemistry Research group, Research Institute of Petroleum Industry (RIPI), Tehran, Iran.
Mater Sci Eng C Mater Biol Appl. 2015;52:151-4. doi: 10.1016/j.msec.2015.03.058. Epub 2015 Mar 26.
In this article we report the application of non-Faradaic mode of electrochemical impedance spectroscopy (EIS) for determination of potassium ion (K(+)) concentration using a guanine rich K(+)-selective aptasensor (K(+)-aptasensor). This is a simple, electroactive probe free, sensitive and reproducible method allowing determination of K(+) ion concentration without any disturbance from electroactive probes used in similar works based on the Faradaic EIS method. Herein, a wide linear range of K(+) ion concentrations (1 μM-0.1mM) with a 200 nM limit of detection was achieved which is better than most of the previously reported Faradaic biosensing methods. The proposed method maintains valuable applications when it is used for K(+) determination in the presence of potentially important interferences in biological media. Thus, application of the non-Faradaic EIS method for sensing the concentration of K(+) ion with the presented K(+)-aptasensor can find an important role in clinical assay.
在本文中，我们报告了非法拉第模式的电化学阻抗谱（EIS）在使用富含鸟嘌呤的钾离子（K⁺）选择性适配体传感器（K⁺ - 适配体传感器）测定钾离子（K⁺）浓度方面的应用。这是一种简单、无需电活性探针、灵敏且可重复的方法，能够在不受基于法拉第EIS方法的类似研究中所用电活性探针干扰的情况下测定K⁺离子浓度。在此，实现了K⁺离子浓度的宽线性范围（1 μM - 0.1 mM），检测限为200 nM，这优于大多数先前报道的法拉第生物传感方法。当该方法用于在生物介质中存在潜在重要干扰物的情况下测定K⁺时，仍具有重要应用价值。因此，使用所提出的K⁺ - 适配体传感器，非法拉第EIS方法在检测K⁺离子浓度方面的应用在临床检测中可发挥重要作用。
