Development of a Cu@ERGO-p(L-Lys) Modified GCE Electrochemical Sensor for the Simultaneous Detection of Ascorbic Acid, Dopamine, and Uric Acid

In this work, a sensitive sensing platform was developed using a glassy carbon electrode (GCE) to simultaneously determine AA, DA, and UA. Cu nanostructures, the poly-L-Lysine (p(L-Lys)), and the electrochemically reduced graphene oxide (ERGO) modified GCE (GCE/Cu@ERGO-p(L-Lys)) was developed via the electrodeposition of Cu and electropolymerization of the ERGO-p(L-Lys). Simultaneous detection makes analysis more efficient and cost-effective by reducing the need for multiple sensors. The GCE/Cu@ERGO-p(L-Lys) was characterized by electrochemical impedance spectroscopy, cyclic voltammetry, and scanning electron microscopy. The limit of detection values for AA, DA, and UA analytes were 0.16, 0.033, and 0.021 mu M, respectively, while the linear ranges were 0.53-50.0, 0.11-100.0, and 0.070-0.75 mu M. The proposed sensor was found to be applicable for the determination of target analytes in fetal bovine serum samples. The proposed GCE/Cu@ERGO-p(L-Lys) hybrid composite modified electrode is a promising material for simultaneous determination in biological fluids with excellent analytical performance and anti-interference effect.

The developed GCE/Cu@ERGO-p(L-Lys) sensor was characterized by SEM, EIS, and CV techniques.The GCE/Cu@ERGO-p(L-lys) sensor was successfully performed to detect AA, DA, and UA simultaneously.The proposed sensor was simple, rapid, stable, reproducible, high selectivity.The limit of detection values for AA DA, and UA analytes were 0.16 mu M, 0.033 mu M, and 0.021 mu M respectively.The developed sensor is a promising material for the analysis of biomolecules in bodily fluids.