Nile red is a lipophilic stain. Nile red stains intracellular lipid droplets yellow. In most polar solvents, Nile red will not fluoresce; however, when in a lipid-rich environment, it can be intensely fluorescent, with varying colors from deep red to strong yellow-gold emission. Wikipedia Molar mass: 318.369 g/mol Formula: C20H18N2O2 3D model (JSmol): Interactive image CompTox Dashboard (EPA): DTXSID7064653 ECHA InfoCard: 100.028.151 PubChem CID: 65182