Abstract:

A carbon paste electrode used as the working electrode, the electrochemical behavior of erythromycin[JP] ethylsuccinate(EEs) was investigated by cyclic voltammetry(CV) and differential pulse voltammetry(DPV), a novel method was proposed for the determination of EEs. The results showed two irreversible anodic peaks appeared at 0.83 V and 0.97 V, respectively in 0.1 mol/L PBS buffer solution(pH=8.0), indicating that there were two-step irreversible oxidations. Quantitative measurements by chronoamperometry(I-t) showed that the peak currents were proportional to erythromycin ethylsuccinate concentration in the range of 2.0×10-7~2.8×10-6 and 2.8×10-6~3.1×10-5 mol/L, respectively, with the detection limit(S/N=3) of 1.0×10-7 mol/L. The recovery was in the range of 95.0%～98.8% with a RSD of 3.4%(n=3). The method showed a high selectivity and sensitivity, and could be used for the determination of EEs in the drugs with satisfactory result.

Key words: erythromycin ethylsuccinate, carbon paste electrode, electrochemical determination, chronoamperometry (I-t)