Advanced characterization

Development and implementation of advanced characterization methods: Friction measurements, conductive AFM and Surface Potential, Force Volume measurements. These techniques allow the characterization of physical and chemical properties of the surfaces, and are complemetary (and simultaneous) with respect to the topographic analysis.
The Surface Potential technique measures the local tip-surface contact potential: this measurement provides information about the conductivity, oxidation state, contaminant presence on the surface or just underneath.
Force Volume is often perfomed using a chemically functionalizated tip: it is possibile to measure the interaction between specific molecules pair (proteins, antibodyes, etc.). This technique allows measurement in the pico Newton range.

Force Volume experiment: a biotynilated SiO2 particle previously attached to a tipless cantilever has been brought in contact with a mica surface functionalizated with a streptavidin layer. 256 force-distance curves were analyzed; the resulting occurrence of detaching forces is show in dark-green. After that, both the surface and the cantilever were rinsed with a surfactant solution, then rinsed in PBS.