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

Abstract

Sulfur dioxide (SO₂) is considered as the fourth gas signal molecule after nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H₂S). It plays important roles in several physiological processes. Therefore, the design and synthesis of nanoprobes for the detection of SO₂ 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 SO₂ derivatives. The proposed ratiometric fluorescence assay allows the determination of HSO₃⁻ 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 HSO₃⁻ over other chemical species including H₂S and biological mercaptans. Quantitation of HSO₃⁻ in cell lysates by using the nanoprobe is demonstrated.