A 6-acetyl-2-naphthol based two-photon fluorescent probe for the selective detection of nitroxyl and imaging in living cells

A novel two-photon HNO fluorescent probe (TP-HNO) was easily constructed and prepared by combining 6-acetyl-2-naphthol and 2-(diphenylphosphino)-benzoate. TP-HNO exhibited high selectivity (more than 140-fold off–on fluorescence response) and high sensitivity (the detection limit is 78 nM) to HNO in solution. TP-HNO was also applied for two-photon imaging of HNO in living cells and in tissues.