Figure 2.

Spectral shape and energy transfer vs. bound ligands at 20°C using short-linker donor. The emission data were acquired beginning 150 μsec after the excitation pulse, thereby eliminating all prompt fluorescence. The curves are normalized at 545 nm. Inset is the enlarged view from 555 to 580 nm to emphasize the sensitized emission. The differences in sensitized emission indicate different amounts of energy transfer. Total integration time was 5–10 seconds (200–400 excitation pulses) with 0.35-nm resolution.