Simultaneous Determination of Ranitidine and Metronidazole at Low Potential Using an Acid-Activated Glassy Carbon Electrode

A simple, highly sensitive and inexpensive electrochemical method was established using an activated glassy carbon electrode (AGCE) in an acidic condition for the determination of ranitidine (RT) and metronidazole (MT) simultaneously at a low potential range. The AGCE was characterized using various techniques such as electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and morphology was studied through field-emission scanning electron microscope (FE-SEM). The AGCE exhibited an electrocatalytic behavior towards the reduction of RT and MT in 0.5 M acidic solution. Both CV and DPV responses for the mixture of RT and MT gave well-resolved peaks at low potential. Analysis of these experiments helps us to predict interactions that took place on the surface of AGCE and RT and MT with each other for having different types of functional groups. Furthermore, AGCE also promoted the electron transfer process. The linear dynamic range of MT and RT was 0.5-580 mu M and 0.5-500 mu M, respectively with the regression coefficient 0.99. The detection limit (S/N=3) calculated for MT and RT was 0.062 mu M and 0.13 mu M, respectively. Decent results were obtained from the reproducibility and stability test. The performance of the sensor was evaluated for the possible interferences which show high selectivity. Additionally, the real sample analysis was carried out to understand our sensor's applicability in real life.