title: Chiral sensing using an achiral europium(III) complex by induced circularly polarized luminescence.
abstract: [Eu(bda)(2)](-) (bda = 2,2'-bipyridine-6,6'-dicarboxylic acid) produces intense circularly polarized luminescence (CPL) in aqueous solutions in the presence of (S)-2-pyrrolidone-5-carboxylic acid upon UV irradiation, although the molecular structure of the europium(III) complex is achiral. The mechanism for the induction of CPL was preliminarily attributed to distortions induced by association with an amino acid to generate chirality in the achiral complex. The optical anisotropy factor (g(lum) value) for the (5)D(0) → (7)F(1) transition was 0.03 in the presence of 1.0 mol dm(-3) of the amino acid. Analysis of the CPL intensity as a function of the amino acid concentration gave an association constant between those of [Eu(bda)(2)](-) and the amino acid, K(aso) = 0.55 ± 0.09 mol(-1) dm(3). These results demonstrate the potential of [Eu(bda)(2)](-) to act as a luminescent chiral-sensing reagent in microscopic spectroscopy.
authors.affiliation: Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555, Japan. miwamura@sci.u-toyama.ac.jp
authors.forename: Munetaka
authors.initials: M
authors.lastname: Iwamura
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kimura
authors.forename: Risa
authors.initials: R
authors.lastname: Miyamoto
authors.forename: Koichi
authors.initials: K
authors.lastname: Nozaki
mesh_terms: D015082:2,2'-Dipyridyl / Q000737:chemistry*; D016880:Anisotropy; D056831:Coordination Complexes / Q000737:chemistry*; D005063:Europium / Q000737:chemistry*; D007700:Kinetics; D049449:Luminescence; D008163:Luminescent Measurements; D008859:Microscopy, Polarization; D015335:Molecular Probes / Q000737:chemistry*; D015394:Molecular Structure; D009539:Nicotinic Acids / Q000737:chemistry*; D011761:Pyrrolidonecarboxylic Acid / Q000737:chemistry; D012996:Solutions; D013050:Spectrometry, Fluorescence; D013237:Stereoisomerism; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry
chemical_list: D056831:Coordination Complexes; D015335:Molecular Probes; D009539:Nicotinic Acids; D012996:Solutions; D014867:Water; D005063:Europium; D015082:2,2'-Dipyridyl; D011761:Pyrrolidonecarboxylic Acid