A fluorescence "turn-on" probe for the detection of HSO3- based on a pyrene-functionalized mesoporous silica material

The sensitive detection of bisulfite residues (HSO3-) is of great importance for ecosystems and public health. In order to overcome the problems of poor water dispersion stability and low sensitivity of HSO3- detection systems, an organic-inorganic hybrid mesoporous silica material PYA-SBA-15 was prepared, by introducing a pyrene fluorophore and different kinds of nitrogen-containing functional groups onto SBA-15. PYA-SBA-15 was developed as a fluorescent probe for the detection of HSO3- with high selectivity and sensitivity, and PYA-SBA-15 was applied for detecting HSO3- in practical samples such as tap water (RSD < 2.3%). Upon adding HSO3-, the fluorescence intensity of PYA-SBA-15 at 383 and 398 nm enhanced significantly, which was attributed to the Michael addition reaction between the carbon-nitrogen double bonds in PYA-SBA-15 and HSO3-. This work provided a simple and effective strategy for designing HSO3- detection systems with superior properties, such as "turn-on" fluorescence response and application in an aqueous environment without resorting to organic solvents.