ENERGY-TRANSFER BETWEEN 1,3-DIMETHYLXANTHINE AND EUROPIUM(III) IN AQUEOUS-SOLUTION

Luminescence of 1,3-dimethylxanthine in solution is impaired owing to collisional deactivation by solvent molecules and matrix interferences. Energy absorbed by 1,3-dimethylxanthine has been transferred to trivalent europium which emits narrow-band radiation in a region distant from background interferences. The enhanced luminescence of trivalent europium was utilized for the determination of 1,3-dimethylxanthine in buffered aqueous solution. An analytically useful range from 1.1 × 10-5-5.0 × 10-4 M and a detection limit of 1.1 × 10-5 M were obtained. The methodology for the analytical procedure was determined. © 1990.