An aryleneethynylene fluorophore for cell membrane staining

► An aryleneethynylene-based fluorophore as a suitable cell membrane marker is demonstrated. ► Structural flexibility of the oligo-aryleneethynylene fluorophores. ► Chemical and fluorescence stability in a wide pH range. ► Fast staining and good photostability for live cell imaging. ► A new blue membrane marker for multicolor labeling in immunofluorescence experiments.