rGO/ZnO Nanocomposite Modified Carbon Paste Electrode as Sensor for Tyrosine Analysis

Tyrosine is an important amino acid with wide application in human body. So, we try for fabrication of a fast electrochemical tyrosine sensor based on carbon paste electrode modified with reduced graphene oxide/ZnO nanocomposite (rGO/ZnO-NC/CPE). In the first step, we synthesized rGO/ZnO by chemical precipitation method and characterized by SEM and EDAX methods. The rGO/ZnO-NC/CPE showed highly catalytic activity to tyrosine electro-oxidation in aqueous solution. The anodic peak current of tyrosine increased with concentration of this amino acid in the ranges of 0.1–400 μM with limit of detection ~0.07 μM. The performance of rGO/ZnO-NC/CPE was check for the analysis of tyrosine in water and pharmaceutical serum samples.