Trace Determination of Uranyl Ion Using a Blue Led as Excitation Source in Phase-Resolved Luminescence Spectroscopy

A phase-resolved luminescence system based on the use of a light emitting diode (LED) is applied to the trace determination of uranyl ion (UO2 2+). The system performance is evaluated, phase resolved spectra of UO2 2+ are shown as well as its lifetime determination using multifrequency phase resolved measurements. Analytical figures of merit are also presented for this system. A limit of detection (LOD) of 10 μg/L is obtained at the blue LED excitation wavelength of 460 nm and its results compare well with a conventional system. Also, a linear dynamic range of ca. 5 orders of magnitude is observed. In situ quenching correction of the analytical signal was evaluated and was applied to a real sample for uranyl determination.