Comprehensive studies published in Micron, 2010:
The paper describes for the first time that optical resolution of cellular structures in the lamda/10 range (about 50 nm) can be achieved even in label-free cells using the localization microscopy SPDM (Spectral Precision Distance/Position Determination Microscopy).
Beside a substantial resolution improvement of autofluorescent structures, SPDM revealed cellular objects with are not detectable under conventional fluorescence imaging conditions.
Rainer Kaufmann, Patrick Müller, Michael Hausmann, Christoph Cremer: Imaging label-free intracellular structures by localisation microscopy. Micron (2010), doi:10.1016/j.micron.2010.03.06