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Updated: Jun 5, 2026

Automated System for Single Molecule Fluorescence Measurements of Surface-immobilized Biomolecules
Published on: November 2, 2009
A photoprotection strategy for microsecond-resolution single-molecule fluorescence spectroscopy
Luis A Campos1, Jianwei Liu, Xiang Wang
1Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain.
Abstract:
Time resolution of current single-molecule fluorescence techniques is limited to milliseconds because of dye blinking and bleaching. Here we introduce a photoprotection strategy that affords microsecond resolution by combining efficient triplet quenching by oxygen and Trolox with minimized bleaching via the oxygen radical scavenger cysteamine. Using this approach we resolved the single-molecule microsecond conformational fluctuations of two proteins: the two-state folder α-spectrin SH3 domain and the ultrafast downhill folder BBL.
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