Voltammetric determination of ampicillin and penicillin G at a mercury meniscus modified silver amalgam electrode

Abstract

Due to the toxicity of mercury, an alternative electrode has to be constructed still having the unique properties of mercury electrode. Thus, mercury meniscus modified silver amalgam electrode (m-AgSAE) was constructed to overcome this problem and to be the suitable replacement commercial mercury electrode. The voltammetric behavior of antibiotic drugs (ampicillin and penicillin G) had been studied using m- AgSAE with Ag/AgCl (3M KCl) as the reference and the measurement was conducted in Britton-Robinson buffer (BRB). Differential pulse voltammetry (DPV) and adsorptive stripping voltammetry (AdSV) techniques were used to conduct these studies. This study was done to observe and study the capability of m-AgSAE properties that can match with commercial mercury electrode. The optimal conditions for ampicillin and penicillin G determination were successfully evaluated in the concentration range of 10 μmol/L to 90 μmol/L. The limits of detection for ampicillin and penicillin G at m- AgSAE were found to be 3.8 μmol/L and 2.5 μmol/L respectively. Using the optimum conditions, the practical application of the newly developed method has been verified on the determination of ampicillin and penicillin G in spiked samples of drinking and river water.