A unique colorimetric and ratiometric reversible fluorescent probe for HSO3−/H2O2 detection and imaging in real water samples, rice leaves and roots

A reversible colorimetric and ratiometric fluorescent probe (QG-Py) was developed for HSO3− detection. The probe showed large changes in absorbance and emission wavelength shift both with 155 nm when reacted with NaHSO3. Furthermore, probe QG-Py exhibited high selectivity and sensitivity to NaHSO3 with quantitative analysis in real water samples through colorimetric and ratiometric methods. Interestingly, the reaction product (QG-Py-SO3H) displayed structural recovery to QG-Py induced by H2O2, accompanied with reversible optical properties. Probe QG-Py was established to visualize HSO3−/H2O2 in MCF-7 cells. Importantly, QG-Py was also successfully applied for HSO3−/H2O2 detection and imaging in rice roots and leaves, providing better understanding of the influence of SO2 derivatives to crops, as well as a new and simple method for evaluating environmental pollution of SO2.