Water-Soluble Fluorescent Probe with Dual Mitochondria/Lysosome Targetability for Selective Superoxide Detection in Live Cells and in Zebrafish Embryos.

A novel water-soluble fluorescein-based fluorescent probe for superoxide detection was developed. The probe is fairly stable under neutral and acidic conditions. It can be used to detect superoxide both in solution with the detection limit of 2.2 μM and in living cells. Cell imaging experiments indicated that such a probe displayed good cell penetration and O2•- could be detected with PMA-stimulated HepG2 cells in both mitochondria and lysosome. Such a probe is the first dual mitochondria- and lysosome- targetable fluorescent chemodosimeter. Additionally, O2•- in intact live zebrafish embryos was successfully visualized under PMA-stimulated conditions, and the possible detection mechanism was studied as well.