Di-4-ANEPPS A89223 (E)-3-(4-(2-(6-(dibutylamino)naphthalen-2-yl)vinyl)pyridin-1-ium-1-yl)propane-1-sulfonate
Di-4-ANEPPS is a fast-response voltage-sensitive dye that partitions into lipid bilayers and reports changes in membrane electric fields through rapid, intensity-based fluorescence responses. It is widely used for optical measurements of membrane potential and fast electrical activity in excitable cells as well as in model membranes such as liposomes and supported/planar bilayers.