A simple assay for the detection of Fe^3＋ in water by means of fluorescence spectroscopy was developed based on a commercially available reagent, Azomethine-H（A-H）, allowing sensing trace levels of Fe^3＋ with high...A simple assay for the detection of Fe^3＋ in water by means of fluorescence spectroscopy was developed based on a commercially available reagent, Azomethine-H（A-H）, allowing sensing trace levels of Fe^3＋ with high selectivity over other cations. A significant fluorescence quenching of A-H at 424 nm was found after its binding with Fe^3＋ in 100% aqueous solution at pH=7.0, while other physiologically relevant metal ions posed little interference. The fluorescence responses can be well described by the modified Stern-Volmer equation. A good linear relationship（Re=0.9904） was observed up to 1.6x10 5 mol/L Fe^3＋ ions. The detection limit, calculated via the 3tr IUPAC（international union of pure and applied chemistry） criteria, was 1.95x10-7 mol/L. Moreover, the colorimetric and fluorescent response of A-H to Fe^3＋ can be conveniently detected by the naked eye, providing a facile method for visual detection of Fe^3＋. The proposed method was used to determine Fe^3＋ in water samples. Moreover, inverted fluorescence microscopy imaging using human umbilical vein endothelial cells shows that A-H can be used as an effective fluorescent probe for detecting Fe^3＋ in living cells.展开更多
A new and efficient fluorescent sensor 4＇-hydroxy-3＇-[（4-antipyrineimino）methyl]-4-biphenylcarboni- trile（L） was prepared for the selective detection of Zn2＋ in aqueous ethanol medium. When excited at 419 nm, t...A new and efficient fluorescent sensor 4＇-hydroxy-3＇-[（4-antipyrineimino）methyl]-4-biphenylcarboni- trile（L） was prepared for the selective detection of Zn2＋ in aqueous ethanol medium. When excited at 419 nm, the fluorescent intensity of sensor L at 507 nm was remarkably increased more than 54-fold after adding Zn2＋ ions. The strong green emission of the solution can be easily identified by naked eye tinder UV light. Thus, sensor L behaves as a naked eye fluorescent ＂turn on＂ detector for Zn2＋ ions. The fluorescence enhancement might be attributed to the in- hibition of excited state intramolecular proton transfer（ESIPT） and C==N isomerization as well as the chelation en- hanced fluorescence（CHEF） effect. The complex solution of sensor L with Zn2＋ ions exhibited reversibility with ethylene diamine tetraacetic acid（EDTA） and the probe could be recycled for further use. Notably, sensor L could clearly distinguish Zn2＋ from Cd2＋. The interaction of sensor L with zinc ions was investigated by means of FTIR, 1H NMR and HRMS spectroscopy. Furthermore, sensor L has been applied for cell imaging studies.展开更多
基金Supported by the Project of the Shanxi Scholarship Council, China（No.2011-008）, the Natural Science Foundation of Shanxi Province, China（No.2013011040-6） and the Project Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education, China.
文摘A simple assay for the detection of Fe^3＋ in water by means of fluorescence spectroscopy was developed based on a commercially available reagent, Azomethine-H（A-H）, allowing sensing trace levels of Fe^3＋ with high selectivity over other cations. A significant fluorescence quenching of A-H at 424 nm was found after its binding with Fe^3＋ in 100% aqueous solution at pH=7.0, while other physiologically relevant metal ions posed little interference. The fluorescence responses can be well described by the modified Stern-Volmer equation. A good linear relationship（Re=0.9904） was observed up to 1.6x10 5 mol/L Fe^3＋ ions. The detection limit, calculated via the 3tr IUPAC（international union of pure and applied chemistry） criteria, was 1.95x10-7 mol/L. Moreover, the colorimetric and fluorescent response of A-H to Fe^3＋ can be conveniently detected by the naked eye, providing a facile method for visual detection of Fe^3＋. The proposed method was used to determine Fe^3＋ in water samples. Moreover, inverted fluorescence microscopy imaging using human umbilical vein endothelial cells shows that A-H can be used as an effective fluorescent probe for detecting Fe^3＋ in living cells.
基金Supported by the Natural Science Foundation of Shanxi Province, China（No.2013011040-6）, the Project Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, the Ministry of Education of China.
文摘A new and efficient fluorescent sensor 4＇-hydroxy-3＇-[（4-antipyrineimino）methyl]-4-biphenylcarboni- trile（L） was prepared for the selective detection of Zn2＋ in aqueous ethanol medium. When excited at 419 nm, the fluorescent intensity of sensor L at 507 nm was remarkably increased more than 54-fold after adding Zn2＋ ions. The strong green emission of the solution can be easily identified by naked eye tinder UV light. Thus, sensor L behaves as a naked eye fluorescent ＂turn on＂ detector for Zn2＋ ions. The fluorescence enhancement might be attributed to the in- hibition of excited state intramolecular proton transfer（ESIPT） and C==N isomerization as well as the chelation en- hanced fluorescence（CHEF） effect. The complex solution of sensor L with Zn2＋ ions exhibited reversibility with ethylene diamine tetraacetic acid（EDTA） and the probe could be recycled for further use. Notably, sensor L could clearly distinguish Zn2＋ from Cd2＋. The interaction of sensor L with zinc ions was investigated by means of FTIR, 1H NMR and HRMS spectroscopy. Furthermore, sensor L has been applied for cell imaging studies.
