Collect. Czech. Chem. Commun. 2006, 71, 1333-1349

Terbium Binding in Highly Luminescent Polymer Complexes

Stanislav Kukla, Věra Cimrová and Drahomír Výprachtický*

Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovského nám. 2, 162 06 Prague 6, Czech Republic


Polymer ligands containing a covalently bonded quinolinone fluorophore and COOH (L1) or COONa (L2) binding sites were synthesized by the reaction of high-molecular-weight poly[styrene-alt-(maleic anhydride)] with 7-amino-4-methylquinolin-2(1H)-one and methanol and subsequent neutralization. The ligand-to-metal energy transfer and ligand binding properties in a series of [Tb(III)-ligand] complexes were investigated by steady-state and time-resolved luminescence spectroscopy in methanol or deuterated methanol. The intensity of the long-lived terbium(III) ion emission at 490, 545, 585 and 620 nm was greatly enhanced upon addition of L1 or L2. Based on the differences in luminescence data obtained for [Tb(III)-L1] and [Tb(III)-L2] complexes, a qualitative model for the interaction of terbium(III) ion with L1 and L2 is put forward. The experimental luminescence decay curves were double-exponential (τ1, τ2) with predominating longer component (rel B1 > 85%) for both [Tb(III)-L1] and [Tb(III)-L2] complexes. About 2.5 or 2 methanol molecules were coordinated to Tb3+ in [Tb(III)-L1] or [Tb(III)-L2] complexes, respectively, whereas ca. 6.5 methanol molecules were coordinated to Tb3+ in methanol.

Keywords: Terbium luminescence; Resonance energy transfer; Quinolinone fluorophore; Functionalized polymers; Time-resolved fluorescence spectroscopy; Fluorescent materials; Lanthanides.

References: 42 live references.