title: Detection of Sugars via Chirality Induced in Europium(III) Compounds.
abstract: Detection and resolution of simple monosaccharides are difficult tasks because their structure is quite similar. The present study shows that circularly polarized luminescence (CPL) induced in europium complexes provides very specific spectral patterns for fructose, mannose, glucose, and galactose. Differences were also observed between bare Eu(3+) ion and its complexes, when interacting with these sugars. The CPL spectra were measured on a Raman optical activity (ROA) spectrometer, which ensured high fluorescence intensity owing to the strong 532 nm laser excitation. The induced fluorescence was recorded in the same spectrum as the vibrational Raman bands. On the basis of the ligand field theory, most fluorescence spectral peaks could be assigned to f-shell europium transitions. Additional information on the interaction of the lanthanide with the sugar component was provided by measurement of time-dependent fluorescence, as formation of different complexes led to variations in fluorescence decay times. In nuclear magnetic resonance (NMR), the paramagnetic metal ion interacting with the sugars caused specific changes in (13)C chemical shifts. The spectroscopic data and molecular dynamics modeling showed that the interaction between the monosaccharides and Eu ion is rather weak due to the competition of the OH sugar groups with water molecules. However, multiple binding modes are possible, which contributes to the complexity and specificity of the spectra. The induced chirality and fluorescence spectra thus appear to be convenient means for monosaccharide detection and identification.
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences , Flemingovo náměstí 2, Prague, 16610, Czech Republic.
authors.forename: Tao
authors.initials: T
authors.lastname: Wu
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences , Flemingovo náměstí 2, Prague, 16610, Czech Republic.|Department of Analytical Chemistry, University of Chemistry and Technology , Technická 5, Prague, 16628, Czech Republic.
authors.forename: Jiří
authors.initials: J
authors.lastname: Průša
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences , Flemingovo náměstí 2, Prague, 16610, Czech Republic.|Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University , Hlavova 8, Prague, 12840, Czech Republic.
authors.forename: Jiří
authors.initials: J
authors.lastname: Kessler
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences , Flemingovo náměstí 2, Prague, 16610, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Dračínský
authors.affiliation: Faculty of Mathematics and Physics, Charles University , Ke Karlovu 3, Prague, 12116, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Valenta
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences , Flemingovo náměstí 2, Prague, 16610, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Bouř
mesh_terms: D005063:Europium / Q000737:chemistry*; D049449:Luminescence; D008163:Luminescent Measurements; D009682:Magnetic Resonance Spectroscopy; D056004:Molecular Dynamics Simulation; D013059:Spectrum Analysis, Raman; D000073893:Sugars / Q000032:analysis*
chemical_list: D000073893:Sugars; D005063:Europium