A novel method to determine ciprofloxacin by enhanced electrochemiluminescence of Tb(bpy)23+–K2S2O8 system in aqueous solution

Abstract

A simple and rapid electrochemiluminescence (ECL) method is developed by using Tb(bpy)₂³⁺–K₂S₂O₈ system for the determination of trace amounts of ciprofloxacin (CPFX). Conditions for ECL emission were optimized. Under optimized condition, the linear range of ECL intensity versus concentrations of CPFX is 6 × 10⁻⁸ to 1.0 × 10⁻⁶ mol dm⁻³ with a relative standard deviation (R.S.D.) of 3.8% (n = 11) and the detection limit is 1.4 × 10⁻⁹ mol dm⁻³ for CPFX. The ECL emission spectra (the peaks are at 490, 545, 585 and 620 nm) match the characteristic emission spectrum of Tb³⁺, indicating that the emission is from the excited state of Tb³⁺. The enhanced mechanism of Tb(bpy)₂³⁺–K₂S₂O₈ ECL system was proposed. This method was successfully applied to determine CPFX in tablets.