Prodan is a solvatochromic fluorescent probe.1 It exhibits absorbance/emission maxima of 347/416 nm, respectively, in toluene, with both parameters increasing as solvent polarity increases. The emission maximum is also influenced by the phase state of membranes, such as in multilamellar vesicles containing 1,2-dipalmitoyl-sn-glycero-3-PC wherein the emission maximum of prodan shifts from approximately 440 nm in the gel phase to approximately 490 nm in the liquid crystalline phase.2 Prodan has been used to probe the microenvironmental conditions of biological and synthetic membranes.2,3

|1. Kucherak, O.A., Didier, P., MÉly, Y., et al. Fluorene analogues of prodan with superior fluorescence brightness and solvatochromism. J. Phys. Chem. Lett. 1(3), 616-620 (2010).|2. Parasassi, T., Krasnowska, E.K., Bagatolli, L., et al. Laurdan and prodan as polarity-sensitive fluorescent membrane probes. J. Fluoresc. 8(4), 365-373 (1998).|3. Mennucci, B., Caricato, M., Ingrosso, F., et al. How the environment controls absorption and fluorescence spectra of PRODAN: A quantum-mechanical study in homogeneous and heterogeneous media. J. Phys. Chem. B 112(2), 414-423 (2008).