A new ratiometric fluorescence assay based on resonance energy transfer between biomass quantum dots and organic dye for the detection of sulfur dioxide derivatives.

Sulfur dioxide (SO 2 ) is considered as the fourth gas signal molecule after nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H 2 S). It plays important roles in several physiological processes. Therefore, the design and synthesis of nanoprobes for the detection of SO 2 derivatives in cells is of great significance. Herein, we report a new ratiometric fluorescence nanoprobe based on resonance energy transfer (RET) between biomass quantum dots (BQDs) and organic dye (DMI) for the detection of SO 2 derivatives. The proposed ratiometric fluorescence assay allows the determination of HSO 3 - in the range of 1.0 to 225 μM with a detection limit of 0.5 μM. Importantly, the proposed ratiometric fluorescence nanoprobe exhibits a high photostability and good selectivity for HSO 3 - over other chemical species including H 2 S and biological mercaptans. Quantitation of HSO 3 - in cell lysates by using the nanoprobe is demonstrated.