Synthesis And Application Of Near-infrared Fluorescence Probe For The Detection Of Bisulfite

Bisulfite?HSO₃^–?is a common form of environmental pollutants in the environment,and it is often used as a preservative in food and pharmaceuticals,making it extremely easy for human to ingest HSO₃^– from the outside.However,excessive exogenous HSO₃^– may cause a series of respiratory diseases such as asthma.At the same time,HSO₃^– is produced in human bodies and,as one of the active sulfur species,it is closely related to the occurrence of cardiovascular diseases and nervous system diseases.Therefore,it is important to develop efficient and accurate analytical methods for HSO₃^– detection,especially those that enable qualitative and quantitative detection in body and food samples.Fluorescent probes are considered to be excellent detection techniques due to their high selectivity and sensitivity as well as real-time and non-invasive imaging.Among them,near-infrared fluorescent probes have become the research focus because of their long excitation and emission wavelength,excellent accuracy,and anti-interference features.In this paper,4-methylquinolinium salt and tetrahydrooxonium salt were selected as electron acceptor,respectively,while N-ethylcarbazole 3-carbaldehyde and p-dimethylaminobenzaldehyde were used as electron donors,and C=C was the recognition site in the probe to bisulfite.Three hydrogen sulfite fluorescent probes WY,LY and XC with red-emitting fluorescence were developed.The recognition was achieved due to the nucleophilic addition between probes and bisulfite,accompanying with changes in UV and fluorescence spectra.In simulated conditions,all these three probes feature red-emission(LY(?_max=650 nm),XC(?_max=684 nm),and WY(?_max=430/620 nm))and can specific,sensitive,qualitative and quantitative detect HSO₃^–.When it comes to application,these three probes can be successfully applied for the detection of HSO₃^– in food,like white wine and white sugar.WY,LY and XC can also be made as test plate for HSO₃^– detection in water samples without the aid of instruments.Moreover,qualitative detection of exogenous HSO₃^– in zebrafish and nude mice was also achieved by using these three probes and it is worth noting that XC can be used to detect HSO₃^–/H₂O₂-regulated redox cycles in vivo and in vitro.