Deposition of hydroquinone-thiosulfate on gold by means of anodic oxidation

Abstract

The realization of chemo- and biosensor microarrays by direct micro- and nanopatterning of organized molecular monolayers was the main objective of the present project. Therefore hydroquinone-thiosulfate (naphthoquinone–thiosulfate respectively) has been deposited from aqueous solutions on gold electrodes, by means of anodic oxidation. The oxidation was initiated by an anodic pulse protocol, and the resulting monolayers were characterized by cyclic voltammetry. The investigations extended from the deposition mechanism and the deposition parameters to the fast and selective micro- and nanopatterning of these films. The deposition mechanism was elucidated and the deposition parameters were optimized. This direct micropatterning method for molecular monolayers has an advantage over classical methods, in that, different functionalized layers are not contaminated by each other and furthermore, the method is relatively simple and cheap. The deposition of hydroquinone-thiosulfate from aqueous solution opens up the possibility of creating multifunctional microarrays for many applications including the immobilization of biomolecules.