Nile red is used to localize and quantitate lipids, particularly neutral lipid droplets within cells. Nile red is almost nonfluorescent in water and other polar solvents but undergoes fluorescence enhancement and large absorption and emission blue shifts in nonpolar environments (Excitation/emission maxima ∼552/636 nm in methanol).

We recommend dissolving in high-quality anhydrous DMSO or DMF to attain a stock concentration up to 1 mM.