Translating potentiometric detection into non-enzymatic amperometric measurement of H2O2

TALANTA

卷:232

Article

Yin, Tanji^1,2,4,5  Wang, Hemin^1,2,3  Li, Jinghui^1,2,4,5  Yuan, Baiqing³  Qin, Wei^1,2,4,5 

[1] Chinese Acad Sci, Yantai Inst Coastal Zone Res YIC, Key Lab Coastal Environm Proc & Ecol Remediat, Yantai 264003, Shandong, Peoples R China

[2] YICCAS, Shandong Prov Key Lab Coastal Environm Proc, Yantai 264003, Shandong, Peoples R China

[3] Ludong Univ, Sch Chem & Mat Sci, Yantai 264025, Shandong, Peoples R China

[4] Pilot Natl Lab Marine Sci & Technol, Lab Marine Biol & Biotechnol, Qingdao 26620, Peoples R China

[5] Chinese Acad Sci, Ctr Ocean Megasci, Qingdao 266071, Shandong, Peoples R China

关键词: Ion-selective electrodes;    Amperometric readout;    H2O2;    Ca2+;    NO3-;   

DOI  :  10.1016/j.talanta.2021.122489

来源: Elsevier

【 摘 要 】

The developments of alternative signal readout strategies for the ion-selective electrodes (ISEs) are necessary in order to break through the limitation of the Nernst equation. In this work, a simple, convenient and easily operated strategy based on the non-enzymatic amperometric measurement of H2O2 is proposed to read out the potentiometric responses for the ISEs. The proposed amperometric signal readout based on H2O2 is carried out in a two compartment electrochemical cell configuration containing a detection cell and a sample cell, physically connected by a salt bridge. A glassy carbon (GC) electrode is placed in the detection cell to monitor the oxidation current of H2O2, and an ISE is placed in the sample cell to act as both the reference electrode and the potentiometric sensor for obtaining the ion activities. The oxidation of H2O2 is induced by a constant potential applied between the GC electrode and the ISE, and subsequently modulated by the potential change of the ISE in the presence of the primary ion. The proposed amperometric signal readout based on H2O2 shows the satisfied slope sensitivity and detection limit, which are better than or compared to those for the potentiometric responses for the ISEs. This work provides a general strategy for transforming the potential response of the ISEs into the amperometric readout, and is promising for detection of cations (eg., Ca2+) and anions (eg., NO3-) with high sensitivity and excellent selectivity.

【 授权许可】

Free