2010, DeRocco et al., "Four-color single-molecule fluorescence with noncovalent dye labeling to monitor dynamic multimolecular complexes", BioTechniques, vol 49, no 5, pg. 810. We confirmed that the same sample when measured with our two-color smFRET microscope yielded consistent FRET efficiency results (0.31) when using γ specific for that instrument (0.94).
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