title: A ratiometric fluorescent detection of Zn(II) in aqueous solutions using pyrene-appended histidine.
abstract: A fluorescent chemosensor, Py-His, based on histidine was easily synthesized in solid phase synthesis. Py-His displayed a highly sensitive ratiometric response to Zn(II) with potent binding affinity (Ka = 1.17 × 10(13)M(-2)) in aqueous solutions. The detection limit of Py-His for Zn(II) was calculated as 80.8 nM. Moreover, Py-His distinguished Zn(II) and Hg(II) by different ratiometric response type; the chemosensor showed a more enhanced increase of excimer emission intensity to Zn(II) than Hg(II). Upon addition of Ag(I) and Cu(II), Py-His showed a turn-off response mainly due to the quenching effect of these metal ions. The binding stoichiometry (2:1 or 1:1) of Py-His to target metal ions played a critical role in the fluorescent response type (ratiometric and turn off response) to target metal ions. The role of imidazole group of Py-His for ratiometric detection of Zn(II) was proposed by pH titration experiments.
authors.affiliation: Bioorganic Chemistry Laboratory, Department of Chemistry and Chemical Engineering, Inha University, 100 Inha-ro, Nam-Gu, Incheon 402-751, Republic of Korea.
authors.forename: Ponnaboina
authors.initials: P
authors.lastname: Thirupathi
authors.forename: Keun-Hyeung
authors.initials: KH
authors.lastname: Lee
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry; D006639:Histidine / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000737:chemistry; D008670:Metals / Q000737:chemistry; D011721:Pyrenes / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry; D015032:Zinc / Q000032:analysis*
chemical_list: D005456:Fluorescent Dyes; D007477:Ions; D008670:Metals; D011721:Pyrenes; D012996:Solutions; D014867:Water; D006639:Histidine; C030984:pyrene; D015032:Zinc
keywords: Chemosensor; Fluorescence; Pyrene; Ratiometric; Zn(II)