Direct electrogenerated chemiluminescence detection in high-performance liquid chromatography for determination of ofloxacin

Ofloxacin (OFLX) exhibited strong electrogenerated chemiluminescence (ECL) in NaNO₃ solution with a dual-electrode system when constant current was exerted. Based on this observation, a sensitive direct ECL method coupled with high-performance liquid chromatography (HPLC) separation was developed for determination of OFLX in human serum. Factors affected the ECL emission were investigated. Under the optimal conditions, the ECL intensity has a linear relationship with the concentration of OFLX in the range of 1.0 × 10⁻⁸ to 4.0 × 10⁻⁶ g mL⁻¹ and the detection limit was 4 × 10⁻⁹ g mL⁻¹ (S/N = 3). The proposed method was sensitive, simple and convenient to operate.