Self assembled gold nanoparticle films on thiol-terminated Substrates for the determination of dopamine and ascorbic acid

The design of new nanoscale materials has acquired ever greater importance in recent years due to their wide-ranging applications in various fields. Among these materials, metallic nanoparticles are of great interest due to their important properties and their numerous possible applications [1, 2]. The metal nanoparticles have size dependent unique chemical, electrical and optical properties and are very promising for practical applications in diverse fields [3]. The nanoparticles are very different from bulk materials and their electronic, optical and catalytic properties originate from their quantum scale dimensions (< 2 nm) [4].In this work the use of gold nanoparticles (GNs) chemically modified electrode to the electroanalysis of ascorbic acid (AA) and dopamine (DA) was studied. The GNs could be efficiently immobilized on binary mixed self-assembled monolayers (SAMs) on a gold surface composed of 1, 6-hexanedithiol (HDT) and 1-octanethiol (nano-Au / SAMs gold electrode). The result showed that the GNs modified electrode could clearly resolve the oxidation peaks of AA and DA, enabling determination of AA and DA in the presence of each others