A Novel Water-soluble Triphenylamine-based Fluorescent Probes for Real-time Monitoring of HSO3⁻/SO32⁻ in Food Samples and Living Cells.

Abstract

Sulfur dioxide (SO₂) is ubiquitously present in environmental and biological samples, predominantly as HSO₃^-/SO₃^2- in aqueous solutions. While their controlled utilization underpins industrial and agricultural processes, excessive residual SO₂ poses severe threats to ecological sustainability and physiological homeostasis in organisms. To address the pressing need for rapid, real-time monitoring of these species, we developed a novel D-π-A structured fluorescent probe, TPA-SO₂, engineered through rational integration of triphenylamine as a robust electron-donating moiety. This probe exhibits excellent water solubility. Photophysical experiments revealed that the probe possesses high selectivity, instantaneous response (< 10 s), and a low detection limit (21.4 nM) for SO₂ derivatives in PBS solution. Experimental results demonstrate the probe's applicability for detecting SO₂ residues in various food products and for imaging SO₂ derivatives in living cells.