Simultaneous Electrochemical Determination of Paracetamol and Caffeine using Activated Glassy Carbon Electrode

Herein, we report simultaneous electrochemical determination of Paracetamol (PAR) and Caffeine (CAF) at activated glassy carbon electrode (aGCE) using cyclic voltammetry (CV) and square wave voltammetry (SWV). Comparison was made for cyclic voltammetric response of PAR and CAF at bare glassy carbon electrode (bGCE) and aGCE in 0.1 M phosphate buffer solution (PBS) of pH 7.0. The experimental result showed that the redox process of PAR was both diffusion and adsorption controlled, whereas the oxidation reaction of CAF is diffusion controlled at aGCE. The aGCE showed a linear response to PAR in the concentration range of 10-180 μM when the concentration of CAF was kept constant (25 µM). Similarly, the linear range for CAF was from 10 -95 μM at a constant concentration of 10 μM PAR. The detection limit (LOD) of PAR and CAF was found to be 2.55 μM, 2.36 μM (3σ/m), respectively. The validity of the demonstrated method was checked by using commercial tablet which contain different amount of PA and CAF and satisfactory percent recoveries were obtained.