New Fluoranthene FLUN-550 as a Fluorescent Probe for Selective Staining and Quantification of Intracellular Lipid Droplets

A new class of live cell permeant, nontoxic fluoranthene-based fluorescent probe (FLUN-550) having a high Stokes shift in aqueous medium has been discovered. It showed selective staining of lipid droplets (LDs, dynamic cytoplasmic organelles) at a low concentration without background noise in in vitro live cell imaging of 3T3-L1 preadipocytes, J774 macrophages, MCF7 breast cancer cells, and single-celled, parasitic protozoa Leishmania donovani promastigotes and in vivo nonparasitic soil nematode C. elegans.