Abstract
The degradation of ampicillin and penicillin G has been carried out by oxidation method using mixed metal oxides (MMO) electrodes as the anode. The objective of this paper was to study the electrochemical properties of several types of antibiotic drugs using electroanalytical techniques and to evaluate the efficiency of commercial MMO electrodes for the degradation of the drugs by anodic oxidation.
For electrochemical studies, the determination of ampicillin and penicillin G has been carried out by differential pulse cathodic stripping voltammetry (DPCSV) at a hanging mercury drop electrode (HMDE) using Britton Robinson buffer (BRB). Ampicillin showed a clear peak current at potential -0.25 V at BRB pH 7 with initial and accumulation potential of 0 V, accumulation time of 30 seconds and with 0.02 V/s of scan rate.
For penicillin G determination, the following optimum conditions were used: BRB pH 12, initial potential -0.3 V, accumulation potential of 0 V, and accumulation time of 30 seconds with 0.02 V/s of scan rate. For electrodegradation studies, two mixed metals oxide (MMO) titanium based electrodes have been used in three different mediums: BRB pH 4, tap water and BRB pH 10.
For MMO electrode based on (Ru-Ir-TiO2 (20:30:50)-10 micron), the best medium for degradation of ampicillin was at pH 4 with 100 % degradation in 15 minutes: for penicillin G, pH 10 is the best medium for the degradation. For (Ru-Ir-TiO2 (40:10:50)-10 micron, similar results were obtained i.e. pH 4 was the best medium for ampicillin and pH 12 for penicillin G.