A novel electrochemiluminescence sensor for the determination of diphenidol based on a nano-TiO2/silica sol/PVP/Ru(bpy)32+ modified gold electrode
Abstract
An electrochemiluminescence (ECL) method was developed for the determination of diphenidol based on the sensitizing effect of diphenidol on Ru(bpy)32+, and a nano-TiO2/silica sol/PVP/Ru(bpy)32+ modified gold electrode was prepared for the simple, sensitive and accurate determination of diphenidol; moreover, both the electrochemical behavior and the electrochemical luminescence behavior of Ru(bpy)32+ and Ru(bpy)32+–diphenidol were investigated. The results show that the proposed electrode possessed very good electrochemical activity and electrochemiluminescence response to the Ru(bpy)32+–diphenidol system under the optimum experimental condition, and the linearity of diphenidol concentration to ECL intensity was achieved in the concentration of diphenidol from 1.0 × 10−7 mol L−1 to 1.0 × 10−4 mol L−1 and the detection limit (S/N = 3) was 6.49 × 10−10 mol L−1. Through the parallel determination of 1.0 × 10−5 mol L−1 diphenidol for 7 times, the RSD of results was 3.00%; moreover, the recovery ranging from 96.4% to 105.6% was obtained in the detection of diphenidol tablets and the RSD was 3.75% (n = 5). The proposed method exhibited high selectivity and sensitivity, and the procedure was simplified for sample processing; thus, it could be applied for the analysis of diphenidol with satisfactory results.