Dye-substrate interactions evidenced by fluorescence correlation spectroscopy

Abstract

In this report, we discuss how the nature of the substrate-water interaction may modify the free diffusion of single molecules, then influencing fluorescence correlation spectroscopy measurements. Our results show a strong influence, up to a few micrometers from the interface, of the surface polarity. This effect is assessed through the relative weight of the two dimension diffusion process observed close to the surface.