Enhanced Fluorescence of Eu‐Gd‐Oxolinic Acid‐CTMAB System and Its Application to the Determination of Europium (III) at Ultra‐Trace Amount

Abstract

A fluorescence enhancement phenomenon in the europium‐oxolinic acid (OA)‐CTMAB fluorescence system was observed when Gd³⁺ was added. The fluorescence intensity of the systems was measured (λex = 345 nm, λem = 612 nm) at pH 7.25. Under optimum conditions, a linear relationship between the enhanced fluorescence intensity and the Eu³⁺ concentration in the range of 2.0 × 10⁻¹⁰ − 1.0 × 10⁻⁷ mol/l was observed. The detection limit of Eu³⁺ was 5.2 × 10⁻¹² mol/l (S/N = 3). This method was used for the determination of trace amounts of europium in rare earth samples with satisfactory results.

Keywords:

• Columinescence
• Europium
• Oxolinic acid

Acknowledgements

This work was supported by the Natural Science Foundation of Shandong Province (No. Y2003B02).