Electrochemically reduced graphene oxide/Poly-Glycine composite modified electrode for sensitive determination of l-dopa.

A facile preparation strategy based on electrochemical technique for the fabrication of glycine (Poly-Gly) and electrochemically reduced graphene oxide (ERGO) composite modified electrode was developed. The morphology of the developed composite (ERGO/Poly-Gly) was investigated using field emission scanning electron microscope (FE-SEM). The composite modified glassy carbon electrode (GCE) was characterized using fourier transform-infrared (FT-IR) spectroscopy, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The electrochemical characterization results revealed that ERGO/Poly-Gly modified GCE has excellent electrocatalytic activity. Further, it was employed for sensing of l-dopa in pH5.5. Differential pulse voltammetry (DPV) was used for the quantification of l-dopa as well as for the simultaneous resolution of l-dopa and uric acid (UA). The LOD (S/N=3) was found to be 0.15μM at the proposed composite modified electrode. Determination of l-dopa could also be achieved in the presence of potentially interfering substances. The sensor showed high sensitivity and selectivity with appreciable reliability and precision. The proposed sensor was also successfully applied for real sample analysis.