Voltammetric determination of erythromycin in water samples using a boron-doped diamond electrode: Voltammetric determination of erythromycin in water samples

A new, simple, sensitive, and low-cost voltammetric method using an as-grown boron-doped diamond electrode was developed for the determination of erythromycin in environmental (water) samples. Erythromycin provided an irreversible oxidation peak at a potential of + 0.87 V versus Ag/AgCl/KCl (3 mol/L) electrode in an ammonium acetate buffer (pH 5). Under optimal experimental conditions, square-wave voltammetry was used for the determination of erythromycin. The calibration curves showed good linearity in a concentration range from 6.8 to 68.1 μmol/L with the coefficient of determination R2 = 0.9993. The limit of detection of the proposed method was 1.1 μmol/L. Very good repeatability (n = 7) at three different concentration levels (6.8, 13.6 and 20.4 μmol/L) was obtained (RSD of 2.4, 1.8, 1.6, respectively). The developed square-wave method was successfully applied to the determination of erythromycin in several different water samples with good recovery (from 89 to 107%).