A sensitive molecular imprinted electrochemical sensor based on gold nanoparticles decorated graphene oxide: Application to selective determination of tyrosine in milk

In present study, a sensitive imprinted electrochemical sensor based on cubic gold nanoparticles (cAuNPs) involved in 2-aminoethanethiol (2-AET) functionalized graphene oxide (GO) modified glassy carbon(GC) electrode was developed for determination of tyrosine (Tyr). The prepared nanomaterials were characterized by using scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and reflection-absorption infrared spectroscopy (RAIRS). Tyr imprinted film was constructed by cyclic voltammetry (CV) for 20 cycles in the presence of 80 mM phenol in phosphate buffer solution (pH 7.0) containing 20 mM Tyr. The imprinted electrochemical sensor was validated according to the ICH guideline and found to be linear, sensitive, precise and accurate. The linearity range and the detection limit were obtained as 1.0 x 10(-9) to 2.0 x 10(-8) M and 1.5 x 10(-10) M, respectively. The developed imprinted sensor was successfully applied to milk samples. In addition, the stability and reproducibility of the prepared molecular imprinted electrode were investigated. The excellent long-term stability and reproducibility of the prepared Tyr imprinted electrodes make them attractive in electrochemical sensors. (C) 2014 Elsevier B.V. All rights reserved.