Selective Nanosensing of Copper (ii) Ion Using L-lysine Functionalized Gold Cysteamine Self-assembled Monolayer

Fabrication of a cysteamine (CA) self-assembled monolayer (SAM) modified gold electrode insitu functionalized with L-Lysine (Lys) is presented and described. The fabricated electrode was used for highly selective and sensitive accumulation and the determination of copper ions (Cu) in a nanomolar concentration. Techniques like cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) with an external redox probe (p-Benzoquinone) were used to investigate the layer-by-layer self assembly modification on a gold electrode, monolayer structure and the ion permeation through it. The differential pulse voltammetric (DPV) method was used for determination of Cu. The results indicated that DPV peaks currents have a linear relationship with pCu in the concentration range of 1.0×10 1×10 M, with a correlation coefficient of 0.9982. The detection limit could be estimated 1.2×10 M according to the IUPAC recommendation (3σ).