ABSTRACT
Different techniques have been reported in the literature to
investigate the electrical properties of proteins. In this field, optical
techniques play an important role, which, in most cases, make
use of visible fluorescent proteins (VFPs) [Lidke et al. (2004)]
and of confocal microscopy analysis, like in fluorescence resonance
energy transfer (FRET) and fluorescence lifetime imaging (FLIM)
techniques [Pompa et al. (2004); Wallrabe (2005); Wallrabe et al.
(2002)]. Other important tools for the investigation of this kind
of systems are offered by the surface plasmon resonance (SPR)
technique [Bieri et al. (1999); Neumann et al. (2002); Vidic et al.
(2008, 2006)] and by atomic force microscopy (AFM) [Andolfi
(2006); Bizzarri and Cannistraro (2012); Kivioja et al. (2009);
Raccosta et al. (2013); Wu et al. (2009, 2012); Zhao et al. (2004)].
In particular, the AFM technique represents a very powerful tool
for structural biology studies since it gives access to the molecular
architecture [Biasco (2004); Fotiadis et al. (2002)] and it can be
used to follow and characterize receptor immobilization on selected
biostructured surfaces.
