A Novel Fluorescent Sensor Based on Aryl-furfural Functionalized Barbituric Acid for Recognition and Separation of Hg2+/Fe3+

A novel fluorescent sensor based on 5-(3-nitrophenyl)-furan-2-carbaldehyde functionalized barbituric acid derivative (QS) was successfully synthesized. QS was characterized by H-1 NMR, C-13 NMR and MS. The maximum fluorescence emission wavelength of QS in dimethyl sulfoxide (DMSO) solution was determined to be 498 nm and green fluorescence was emitted under 365 tun ultraviolet lamp. QS showed different fluorescence identification ability for aqueous solution of Hg2+ and Fe3+. Hg2+ can enhance the fluorescence of probe QS to orange, and Fe3+ quenches its fluorescence, thus realizing real-time detection. The limits of detection of QS for Hg2+ and Fe3+ are 3.25 x 10(-8) and 4.0 x 10(-8) mol. L-1, respectively. The fluorescence measurements and MS studies suggest that the binding stoichiometry ratios of QS with Hg2+ and Fe3+ are recognized as 1 : 1, respectively. The possible modes of QS with Hg2+ and Fe3+ are proposed. The addition of H2PO4- caused the fluorescence of QS-Fe recover, indicating that QS can be used for cyclic detection of More importantly, the separation percentages of the solid QS for Hg2+ and Fe3+ are 92.0% and 91.8% in aqueous solution, respectively, indicating that it has excellent ingestion capacity.