title: Ratiometric fluorescence chemosensor based on tyrosine derivatives for monitoring mercury ions in aqueous solutions.
abstract: Ratiometric fluorescent chemosensors 1 and 2 were synthesized based on tyrosine amino acid derivatives with a pyrene fluorophore. 1 and 2 showed high selectivity for Hg(II) ions among 13 metal ions in aqueous solutions. Both 1 and 2 sensitively detected Hg(II) ions in aqueous solutions by ratiometric response without interference of any of the other tested metal ions including Cu(II), Cd(II), Pb(II), and Ag(I) ions. 1 and 2 had tight binding affinities (5.72 × 10(13) M(−2), 1.15 × 10(13) M(−2)) for Hg(II) with nano-molar detection limits. The binding mode was characterized with the help of organic spectroscopic data, which revealed that the methoxyphenyl moieties of 1 and 2 played a vital role in the coordination of Hg(II). The deprotonation of the sulfonamide group is not a critical process for the binding of mercury ions. The methoxyphenyl moiety, sulfonamide group, and the C-terminal amide moiety of 1 and 2 as ligands for Hg(II) played crucial roles in the stabilization of the 2:1 complexes.
authors.affiliation: Bioorganic Chemistry Lab. Center for Design and Applications of Molecular Catalysts, Department of Chemistry and Chemical Engineering, Inha University, 253 Yonghyun-Dong, Nam-Gu, Incheon, 402-751, Korea. leekh@inha.ac.kr.
authors.forename: Ponnaboina
authors.initials: P
authors.lastname: Thirupathi
authors.forename: Ponnaboina
authors.initials: P
authors.lastname: Saritha née Gudelli
authors.forename: Keun-Hyeung
authors.initials: KH
authors.lastname: Lee
mesh_terms: D001665:Binding Sites; D004785:Environmental Pollutants / Q000032:analysis*; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry; D008024:Ligands; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis*; D015394:Molecular Structure; D060327:Solid-Phase Synthesis Techniques; D012996:Solutions; D013050:Spectrometry, Fluorescence; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D004785:Environmental Pollutants; D005456:Fluorescent Dyes; D008024:Ligands; D012996:Solutions; D014867:Water; D014443:Tyrosine; D008628:Mercury