A mitochondria-targeted fluorescent probe for the detection of endogenous SO2 derivatives in living cells

Abstract

A unique fluorescent probe (ZACA) for the monitoring of SO₂ derivatives was developed from coumarin and benzoindoles based on FRET and ICT. ZACA exhibited an active emission signal, large Stokes shift, wide emission window distance, and high photostability. It also possessed many advantages in the ratiometric detection of HSO₃⁻/SO₃²⁻ including low detection limit and high selectivity and sensitivity. Importantly, ZACA was successfully applied in the ratiometric detection of endogenous HSO₃⁻/SO₃²⁻ in living cells with excellent cellular imaging capability (1 μM) and mitochondria-targeting ability (co-localization coefficient: 0.91).