A 4-Methylumbelliferone-based Fluorescent Probe for Sodium New Houttuyfonate

A new fluorogenic probe for sodium new houttuyfonate (SNH) was proposed. 4-Methylumbelliferyl-2,4-dinitrobenzenesulfonate (4-MUDNBS) was a nonfluorescent compound and was synthesized via the one-step reaction of 4-methylumbelliferone (4-MU) with 2,4-dinitrobenzenesulfonyl chloride. In basic media, SNH was decomposed to produce sodium sulfite, which then reacted with 4-MUDNBS to yield highly fluorescent 4-MU, hence leading to the fluorescence increase of the reaction solution. A linear correlation existed between the emission intensity and the concentration of SNH within the range from 0.5 to 15 mu g center dot mL(-1) with a detection limit of 0.15 mu g center dot mL(-1) (3 sigma). The effect of substituents on the benzenesulfonyl moiety of the probe is discussed, and the presence of electronegative groups is favorable for the proposed cleavage reaction.