Synthesis and Characterization of Gold Nanostructures and Their Activity Against Dopamine

Abstract

This research aims to study the incorporation and effective containment of gold nanostructures on a substrate electrode applied to electrochemical sensors for the detection of dopamine. gold nanoparticles (AuNPs) was synthesized using the protocol developed by Turkevich [1]. Additionally gold nanorods (AuNBs) were obtained using the method described by growth Nikoobakht [2]. These nanostructures have been incorporated into a metal substrate mediated self-assembled monolayers (SAMs) for a 4-mercaptopyridine (4MPy), which allows the confinement and effective communication of the nanostructure. Furthermore, to evaluate the anisotropic effect against dopamine response.Chemical and morphological characterization system were used: X-ray photoelectron spectroscopy (XPS), the atomic force microscopy (AFM) (fig 1A), the scanning tunneling microscopy (STM) (fig 1B), and electron microscopy transmission (TEM). Additionally, for the functional characterization of the system, the cyclic voltammetry was used to determine: 1. The crystallographic orientation of the gold substrate; 2. The electrochemically active bare gold substrate and the nanostructures incorporated area, 3. quimidesorción the SAMs; 4. The electrochemical redox response of two probes K3Fe (CN)6 and Ru (NH)6Cl3 to evaluate the anisotropic effect.Finally it was studied by voltammetric square wave detecting dopamine by preparing a calibration curve, which shows that as the concentration of neurotransmitter increases the signal, ie, the peak height ( Ip), it is proportional to the concentration, in both systems the same phenomenon occurs, however, for the device AuNBs formed with has a detection potential differing from the potential detection of a gold surfacer. Acknowledgements: Proyectos Fondecyt Nº 1131062 y 1140192 references: 1.Kimling, J., M. Maier, B., Okenve, Kotaidis V., Boleta, H., Plech *A., Turkevich. (2006). new method for synthesis of gold nanoparticles. J phys Chem 110, 15700. 2.Nikoobakht, B., Mostafa, A. El-Sayed*. (2007). Preparation and Growth Mechanism of Gold Nanorods (NRs) Using Seed-Mediated Growth Method. Chem Mater 15, 1957. Figure 1