Differential pulse voltammetric determination of trace Os(IV) at a sol-gel-ceramic-carbon powder-9-phenyl-3-fluorone composite electrode in flow systems

Abstract

A composite electrode containing sol-gel-ceramic/carbon-powder/chemical-modifier as components was fabricated. This electrode was electrochemically viable and stable under both still and flow conditions. When the chemical modifier used was phenylfluorone, the composite electrode was useful for the sensitive and selective determination of Os(IV) under continuous flow and flow injection regimes. For these two modes, the detection limits were found to be 2.4 × 10-9 M Os(IV) (S/N = 3) and 3.8 ng (500 μL injection of 3.98 × 10-8 M Os(IV), S/N = 3), respectively. Selected substances were investigated for possible interferences. The developed method was utilized for the determination of Os(IV) in various backgrounds.