A mitochondria-targeting highly specific fluorescent probe for fast sensing of endogenous peroxynitrite in living cells

•A highly specific fluorescent probe MBTBE for sensitively detecting ONOO− in living system was reported.•The probe exhibits excellent mitochondria targeting capability in HeLa cells.•The probe was successfully applied for monitoring the fluctuation of endogenous ONOO− levels in HeLa cells.•The scavenging of ONOO− induced by H2S was successfully observed with probe.