Easily fixed simple small ESIPT molecule with aggregation induced emission for fast and photostable “turn-on” bioimaging

An excited state intramolecular proton transfer (ESIPT) fluorogen, due to its easy hydrogen bonding and AIE characteristics, has demonstrated a fast and selective light-up of the cytoplasm of HeLa cells within 20 seconds. Moreover, the low-cost material preparation, fair cytocompatibility, good photostability and wide pH application range all indicate its great potentials for commercialization.