Green Voltammetric Detection of Ophthalmic Drug Nepafenac Using Pencil Graphite Electrode as a Responsive Disposable Electrochemical Sensor

Abstract In this study, the electrochemical properties of nepafenac, used after eye surgery operations, were investigated on a disposable pencil graphite electrode. Cyclic and square wave voltammetry techniques were used to investigate the electrochemical properties of nepafenac. Two peaks at potentials of approximately +0.33 V and +1.03 V in the anodic direction and two peaks at potentials of approximately +0.29 V and +0.08 V in the cathodic direction were observed on the surface of the disposable pencil electrode in acetate (pH 4.8) medium with the cyclic voltammetry technique. The analytical performance of the developed voltammetric technique had good linearity in the concentration range of 0.30 µM to 3.5 µM at pH 4.8. The LOD value of this voltammetric method in acetate (pH 4.8) medium was calculated as 0.035 µM (8.90 ng mL −1 ). For reproducibility, the relative standard deviation (RSD) values for Ia and IIa anodic peak current/potential were found to be 1.45%/0.43% and 1.28%/0.25%, respectively. The voltammetric method was successfully applied to urine and pharmaceutical preparations and the results were compared with the spectrophotometric method.