Graphene oxide-perylene derivative nanocomposite thin films on ITO for amperometric NADH sensing

Abstract

Perylene derivative dyes (PDDs) have attracted considerable attention in optoelectronic and sensing applications due to their highly conjugated structures and remarkable fluorescence properties, enabling efficient redox mediation. In this study, two novel PDDs (P-12 and P-13) were synthesized and reported for the first time. Together with three previously reported derivatives, these compounds were used to prepare nanocomposites with graphene oxide (GO) via ultrasonic mixing. The resulting GO/PDD nanocomposites were subsequently drop-cast onto indium tin oxide-coated glass (ITO) to fabricate GO/PDD/ITO electrodes for amperometric detection of nicotinamide adenine dinucleotide (NADH). Comprehensive characterization using UV-Vis spectroscopy, SEM, FTIR, Raman, XPS, and XRD confirmed the successful integration of PDD molecules onto GO sheets and the formation of stable thin films. Electrochemical studies revealed that the GO/P-5/ITO electrode exhibited the highest electrocatalytic activity toward NADH oxidation, attributed to enhanced electron transfer mediated by PDD molecules within the otherwise poorly conductive GO matrix. Under optimized conditions, the sensor showed a linear response over the range of 10.9-800 & micro;M, with a limit of detection of 3.3 & micro;M and a sensitivity of 0.30 & micro;A & micro;M-1 cm-2. The sensor exhibited satisfactory recoveries in isotonic serum, whereas matrix-dependent signal suppression was observed in complex samples such as energy drink and milk due to interfering electroactive species. These findings indicate that the developed platform is more suitable for low-interference biological media. These results highlight that GO/PDD/ITO electrodes provide a promising platform for efficient NADH sensing.