Cobalt hexacyanoferrate electrodeposited on electrode with the assistance of laponite: The enhanced electrochemical sensing of captopril

In this work, Co2+ ions were initially intercalated into the layers of laponite and then cobalt hexacyanoferrates (CoHCFe) were electrogenerated on the surface of laponite-Co2+ modified ITO via square wave voltammetry (SWV). At scan rate of 10 mV s(-1), the electrochemical response of the ITO/ laponite/CoHCFe showed two pairs of well-defined redox peaks located about 0.44 and 0.672 V vs. SCE, attributed to the redox reaction of Co-II/Co-III and Fe-II/Fe-III, respectively. The modified electrode was highly electrocatalytic to the captopril oxidation. Moreover, the ITO/laponite/CoHCFe exhibited an enhanced analytical performance for amperometric detection of captopril with two enlarged linear ranges from 3.0 x 10(-7) to 1.27 x 10(-4) M and 1.63 x 10(-4) to 3.76 x 10(-4) M and a low detection limit (0.29 mu M). The modified electrode was used for electrocatalytic determination of captopril in some real samples. (C) 2016 Elsevier Ltd. All rights reserved.