Breaking the diffraction limit of light-sheet fluorescence microscopy by RESOLFT
Authors: Hoyer P, de Medeiros G, Balázs B, Norlin N, Besir C, Hanne J, Kräusslich HG, Engelhardt J, Sahl SJ, Hell SW, Hufnagel L
CellNetworks People: Hell Stefan, Kräusslich Hans-Georg
Journal: Proc Natl Acad Sci U S A. 2016 Mar 29;113(13):3442-6. doi: 10.1073/pnas.1522292113

We present a plane-scanning RESOLFT [reversible saturable/switchable optical (fluorescence) transitions] light-sheet (LS) nanoscope, which fundamentally overcomes the diffraction barrier in the axial direction via confinement of the fluorescent molecular state to a sheet of subdiffraction thickness around the focal plane. To this end, reversibly switchable fluorophores located right above and below the focal plane are transferred to a nonfluorescent state at each scanning step. LS-RESOLFT nanoscopy offers wide-field 3D imaging of living biological specimens with low light dose and axial resolution far beyond the diffraction barrier. We demonstrate optical sections that are thinner by 5-12-fold compared with their conventional diffraction-limited LS analogs.