Dual-functional fluorescent probe for rapid monitoring of bisulfite and viscosity in biosystem and foods.

This study introduces MYT, a novel bifunctional fluorescent probe engineered within a single molecular architecture to concurrently detect bisulfite/sulfur dioxide (HSO3-/SO2) species and measure local viscosity. The probe exhibits an ultrafast response to bisulfite, reaching signal stability within a mere 10 s. Through two well-resolved emission channels, MYT enables the efficient and precise quantification of both HSO3-/SO2 and viscosity. The sensor demonstrates outstanding analytical capability for HSO3-/SO2, featuring a remarkably low limit of detection of 0.182 μM. Live-cell imaging studies confirm MYT's capacity to monitor viscosity alterations in living organisms, specifically in zebrafish. Furthermore, the probe allows for detailed visualization of HSO3-/SO2 fluctuations within rice root tissues. Its practical utility was further established by successfully quantifying HSO3-/SO2 levels in food and water specimens, with recovery rates spanning 92.9% to 107.6%. This underscores the probe's excellent tolerance to complex matrices and its significant potential for environmental monitoring and biological applications.