Skip to main content
. 2013 Apr 18;8(4):e57018. doi: 10.1371/journal.pone.0057018

Figure 7. Operational regime of different FRET methods.

Figure 7

Conventional smFRET and fluorometric assays are difficult to perform in the intermediate concentration regime (100 pM to 1 nM, shaded area). Quasi-bulk smFRET and microplate-scanning FRET (μpsFRET), on the contrary, allow us to accurately determine FRET efficiencies in this regime and effectively close the gap between single molecule and ensemble FRET spectroscopy. A large range of sample concentrations is now amenable to fast, high throughput estimation of bulk FRET efficiencies (μpsFRET) as well as to a detailed analysis of conformational heterogeneity within the ensemble (quasi-bulk smFRET).