A novel near-infrared ratiometric fluorescent probe for SO2 detection with a large emission shift

Abstract

Due to the toxicity of SO₂ to the respiratory tract, ingesting an excess of SO₂ can cause some respiratory diseases and lung cancer. Thus, the development of efficient methods for the detection of SO₂ in biological environments is of great importance. In this work, a ratiometric fluorescent probe, MQC, was constructed and applied for SO₂ detection with good selectivity and sensitivity. Probe MQC displayed a near-infrared emission at 715 nm, which underwent a 245 nm blue-shift (470 nm) upon the addition of SO₂. Meanwhile, a color change from fuchsia to colorless was observed before and after the treatment of probe MQC with SO₂. Biological imaging experiments were performed on probe MQC to detect intracellular SO₂ in living cells.