Heterogeneity of fluorescence determined by the method of area-normalized time-resolved emission spectroscopy.

Heterogeneity of fluorescence due to multiple fluorophores or emitter species is a common problem in using fluorescent molecules to probe the structure, dynamics, and properties of microheterogeneous media (micelles, membranes, proteins, etc.) and biological media. Time-resolved emission spectra (TRES) and area-normalized TRES (TRANES) are useful to identify unambiguously emission from a single species (homogeneity) and emission from two species (dual emission). The features in TRANES spectra that are characteristic of solvation dynamics associated with single species and two species, and many other cases are also described.