Determination of silver ions based on the electrogenerated chemiluminescence of silver ions/peroxydisulfate

Abstract

In this work, a simple, sensitive, and selective method for the determination of silver ions (Ag⁺) was proposed on the basis of the enhancement of Ag⁺ on the electrogenerated chemiluminescence (ECL) of peroxydisulfate (S₂O₈²⁻), which can be attributed to the obvious electrocatalytic reduction of S₂O₈²⁻ by Ag⁺, giving rise to more abundant sulfate radical anion (SO₄^•−). Under optimal conditions, a linear range from 4 to 500 nM (R = 0.997) with a detection limit of 2.5 nM (S/N = 3) was achieved for the detection of Ag⁺. The Ag⁺/S₂O₈²⁻ ECL system could not only provide an assay protocol for the determination of Ag⁺ but also offer an effective way to enhance the ECL of S₂O₈²⁻, which may act as a promising platform for the detection of other species such as 4-chlorophenol.

Graphical abstract

ECL-potential curves of 0.1 M PBS (pH 8.5) containing (a) 500 nM AgNO₃, (b) 50 mM K₂S₂O₈, (c) 500 nM AgNO₃ and 50 mM K₂S₂O₈

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