Venue: Edificio Povo 2, via Sommarive nr. 9, Povo (Tn) - Room B105
At 4:00 p.m.
- Paolo Bianchini - Nanophysics Department, Istituto Italiano di Tecnologia, Genova, Italy
A recognized advantage of optical microscopy, since Galileo Galilei's “occhialino” times, lies in the fact that allows non-invasive three-dimensional (3D) imaging of live cells at the submicron scale with high specificity and localization accuracy. In general, it is a well-known paradigm the given inability of a lens-based optical microscope to discern details that are closer together than half of the wavelength of light. Recently the 2014 Nobel Prize in Chemistry “for the development of super-resolved fluorescence microscopy” had honoured Eric Betzig, Stefan Hell and William E. Moerner as the pioneers of this development. Therefore the viewpoint for improving resolution moved from optical solutions to the side of the fluorescent molecule to be detected taking into account the concepts raised by Toraldo di Francia in the 50s and Lukosz late in the 60s. Today, for the most popular imaging mode in optical microscopy, i.e. fluorescence, the diffraction barrier is crumbling and the term “optical nanoscopy”, coined earlier, comes to be a real far field optical microscope available for the scientific community, opening a new window for the understanding of molecular interactions within the biological cell. Within this framework, focusing on the saturated depletion of the markers' fluorescent state by stimulated emission we have pointed our attention to different modalities for realizing STED (stimulated emission depletion) approach. Finally we will discuss targeted and stochastic readout methods and individual molecule 3D super resolution within selective plane illumination. A variety of architectures will be outlined in regard to specific applications demanding for nanoscale investigations.