Skip to main content
. 2010 Nov 3;99(9):3102–3111. doi: 10.1016/j.bpj.2010.09.005

Figure 4.

Figure 4

Sources of static heterogeneity. (A) Sources of static heterogeneity on T1B18 dsDNA standard probed in the presence of different heterogeneity sources. Single position: static heterogeneity on a single molecule in a single position on the FOV. Multiple positions: single molecule moved between multiple different positions on the field of view (FOV) using a scanning stage. Multiple molecules: multiple molecules from a single FOV only. Multiple FOV: multiple molecules from multiple FOVs. Measurement parameters: Integration time, 100 ms; duration of measurement, 5 s; 80 photons/ms per molecule. Results for multiple molecules and multiple FOV from three separately prepared samples, >400 molecules per sample, ∼20 FOV per sample. Results for single position and multiple positions are from 19 molecules, each measured for 5 s in ≥4 different positions within an area of ∼1 FOV, yielding in total 84 distinct, randomly distributed positions across the FOV. This dataset is necessarily small, because only molecules within a small area could be used, and all molecules retained in the analysis were excited for >20 s without bleaching. (B) Magnitudes of static heterogeneity sources calculated using results from panel A. (C) Intermolecular heterogeneity investigated using dsDNA FRET standards shown in Fig. 1. Measurement parameters: Integration time, 100 ms; duration of measurement, 5 s; 80 photons/ms per molecule; three sample repeats for each measurement; >20 FOV per sample; >190 molecules per sample.