A novel electrochemical method for ofloxacin determination based on interaction of ofloxacin with cupric ion
An indirect electrochemical sensing strategy for the determination of ofloxacin (OFL) was developed using cupric ion (Cu2+) as an electrochemical probe. The method was based on the complexation of OFL with Cu2+, which was investigated by UV-visible spectrophotometry and differential pulse voltammetry (DPV). When OFL was added into the electrolyte solution containing Cu2+, the electro-reduction peak current of Cu2+ on glassy carbon electrode (GCE) was decreased. Some influencing factors in terms of pH, quiet time, and reaction time were systematically studied. Under optimal conditions, the Cu2+ reduction peak current difference (ΔI
 p) before and after adding OFL was found to be linear to the concentration of OFL in the range from 1.0 × 10−7 to 1.0 × 10−4 M. The detection limit (3S/N) was 8.2 × 10−8 M. Moreover, the proposed sensor displayed high selectivity and good reproducibility, which was successfully applied to the detection of OFL in pharmaceutical tablet and chicken fodder.