title: Fluorescent metal-organic framework MIL-53(Al) for highly selective and sensitive detection of Fe3+ in aqueous solution.
abstract: Fluorescent metal-organic frameworks (MOFs) have received great attention in sensing application. Here, we report the exploration of fluorescent MIL-53(Al) for highly selective and sensitive detection of Fe(3+) in aqueous solution. The cation exchange between Fe(3+) and the framework metal ion Al(3+) in MIL-53(Al) led to the quenching of the fluorescence of MIL-53(Al) due to the transformation of strong-fluorescent MIL-53(Al) to weak-fluorescent MIL-53(Fe), allowing highly selective and sensitive detection of Fe(3+) in aqueous solution with a linear range of 3-200 μM and a detection limit of 0.9 μM. No interferences from 0.8 M Na(+); 0.35 M K(+); 11 mM Cu(2+); 10 mM Ni(2+); 6 mM Ca(2+), Pb(2+), and Al(3+); 5.5 mM Mn(2+); 5 mM Co(2+) and Cr(3+); 4 mM Hg(2+), Cd(2+), Zn(2+), and Mg(2+); 3 mM Fe(2+); 0.8 M Cl(-); 60 mM NO2(-) and NO3(-); 10 mM HPO4(2-), H2PO4(-), SO3(2-), SO4(2-), and HCOO(-); 8 mM CO3(2-), HCO3(-), and C2O4(2-); and 5 mM CH3COO(-) were found for the detection of 150 μM Fe(3+). The possible mechanism for the quenching effect of Fe(3+) on the fluorescence of MIL-53(Al) was elucidated by inductively coupled plasma-mass spectrometry, X-ray diffraction spectrometry, and Fourier transform infrared spectrometry. The specific cation exchange behavior between Fe(3+) and the framework Al(3+) along with the excellent stability of MIL-53(Al) allows highly selective and sensitive detection of Fe(3+) in aqueous solution. The developed method was applied to the determination of Fe(3+) in human urine samples with the quantitative spike recoveries from 98.2% to 106.2%.
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology (Nankai University), Synergetic Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, China.
authors.forename: Cheng-Xiong
authors.initials: CX
authors.lastname: Yang
authors.forename: Hu-Bo
authors.initials: HB
authors.lastname: Ren
authors.forename: Xiu-Ping
authors.initials: XP
authors.lastname: Yan
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D007501:Iron / Q000032:analysis* / Q000652:urine; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry*; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D005456:Fluorescent Dyes; D009942:Organometallic Compounds; D012996:Solutions; D012997:Solvents; D014867:Water; D000535:Aluminum; D007501:Iron