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Updated: Jul 18, 2026

Ground State Depletion Super-resolution Imaging in Mammalian Cells
Published on: November 5, 2017
Major signal increase in fluorescence microscopy through dark-state relaxation
Gerald Donnert1, Christian Eggeling, Stefan W Hell
1Max Planck Institute for Biophysical Chemistry, Department of NanoBiophotonics, Am Fassberg 11, 37077 Göttingen, Germany.
Abstract:
We report a substantial signal gain in fluorescence microscopy by ensuring that transient molecular dark states with lifetimes >1 micros, such as the triplet state relax between two molecular absorption events. For GFP and Rhodamine dye Atto532, we observed a 5-25-fold increase in total fluorescence yield before molecular bleaching when strong continuous-wave or high-repetition-rate pulsed illumination was replaced with pulses featuring temporal pulse separation >1 micros. The signal gain was observed both for one- and two-photon excitation. Obeying dark or triplet state relaxation in the illumination process signifies a major step toward imaging with low photobleaching and strong fluorescence fluxes.
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