Determination of thickness, dielectric constant of thiol films, and kinetics of adsorption using surface plasmon resonance.

This paper describes the formation of a self-assembled monolayer of 11-mercaptoundecanoic acid (MUA) under different concentrations on a gold sensor disk, monitoring in situ and in real time using surface plasmon resonance spectroscopy (SPR). The film thickness and dielectric constant were determined for a fully formed monolayer using one-color approach SPR. The kinetic studies of the film formation in ethanol solution indicated that the self-assembled monolayer is formed in a two-step adsorption process. In this sense, this unpublished route was applied on the basis of a model where many molecules are adsorbed at an initial step and then can be desorbed and/or rearranged to form a perfect monolayer.