Electrochemiluminescence of an electrocatalytic action of etimicin on Tris(2,2'-bipyridyl)ruthenium(II) immobilized in Nafion modified carbon paste electrode.

A sensitive electrochemiluminescence (ECL) detection of etimicin at Tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy)(3) (2+)]-Nafion modified carbon paste electrodes was developed. The immobilized Ru(bpy)(3) (2+) shows good electrochemical and photochemical activities. Electrochemical and electrochemiluminescence characterizations of the modified carbon electrodes were made by means of cyclic voltammetry and electrochemical impendence spectroscopy. The modified electrode showed an electrocatalytic response to the oxidation of etimicin, producing a sensitized ECL signal. The ECL sensor showed a linear response to etimicin in the range of 8.0-160.0 ng mL(-1) with a detection limit of 6.7 ng mL(-1). This method for etimicin determination possessed good sensitivity and reproducibility with a coefficient of variation of 5.1% (n = 7) at 100 ng mL(-1). The ECL sensor showed good selectivity and long-term stability. Its surface could be renewed quickly and reproducibly by a simple polish step.