A highly selective Cd(II) coordination polymer fluorescent probe for rapid detection of levofloxacin in water and milk

A new Cd(II) coordination polymer, {[Cd(L)(npht)]·4H2O}n (1) was successfully synthesized via hydrothermal method by 1,3-bis(5,6-dimethylbenzimidazol-1-yl)-2-propanol and 3-nitrophthalic acid as ligands. 1 expresses a double-annular shaped 1-D chain, which further extended into a 3-D supramolecular network through classic π···π stacking interactions. Based on the fluorescence resonance energy transfer (FRET) mechanism, 1 can be used as a promising fluorescence probe to detect levofloxacin (LEV) in water with limit of detection 2.1 × 10−8 mol/L and achieved a rapid detection process within 30 s. Thanks to the excellent stability of 1 which can be soaked for a long time without damage and exhibits a very stable reuse effect. After four cycles of use, the detection rate of LEV is only 8% lower than the first time. The performance of 1 for determination of LEV in water and milk was also investigated.
A stable Cd(II) coordination polymer {[Cd(L)(npht)]·4H2O}n (1) was hydrothermally synthesized and characterized. 1 served as a fluorescence sensor to detect levofloxacin in aqueous solution and milk.