Omeprazole as a strong coreactant in the electrochemiluminescence of Ru(bpy)32+

Omeprazole (OPZ) as a high-efficiency coreactant in the electrochemiluminescence (ECL) of Ru(bpy)32+ on a bare Pt electrode has been studied in this paper. Based on the strong enhancement effect of OPZ on the ECL of Ru(bpy)32+, a simple, rapid and sensitive method for the determination of omeprazole has been established. Under the optimum conditions, the logarithmic ECL enhancement versus the logarithmic concentration of OPZ is linear over a wide concentration range of 2.0 × 10−7 to 5.0 × 10−4 M (r = 0.9945), with a detection limit of 2.0 × 10−8 M (6.9 ng/mL, S/N = 3) in a pH = 11.5 100 mM phosphate buffer solution containing 1.0 × 10−4 M Ru(bpy)32+. To demonstrate its applicability, the proposed method was applied in the determination of OPZ in capsules and the recoveries were ranged from 93.3%-106.7%. These provide a possibility to employ the new ECL method for OPZ detection in pharmaceutical preparations. According to the study of electrochemical behavior, ECL behavior and ECL emission spectrum of Ru(bpy)32+/OPZ system, a possible ECL mechanism was proposed.