Fig. 5.

Three excitation-emission spectral signatures. (a) Excitation spectra of Cerulean (Sex D) and Venus (Sex A) (Left), and emission spectra of Cerulean (Sem D) and Venus (Sem A) (Right). These spectra were measured by recording the excitation and emission spectra of living HepG2 cells separately expressing donor (Cerulean) and acceptor (Venus). (b) Fitted pseudo-color images of three excitation-emission spectral signatures (S_D, S_A, S_S) from the excitation and emission spectra (a) using Eq. (2).