Rapid determination of plutonium in urine using flow injection on-line preconcentration and inductively coupled plasma mass spectrometry

A rapid technique for the determination of Pu in urine samples using flow injection (FI) on-line preconcentration, desolvation nebulization using a highly sensitive APEX device and inductively coupled plasma mass spectrometry with a dynamic reaction cell (ICP-DRC-MS) was developed. Using the DRC avoided the necessity to separate Pu from U, and thus made the technique more rapid. Effective preconcentration and matrix separation for urine samples was achieved using TRU resin as the ion exchanger. A detection limit for Pu-242 of 1.9 pg L-1 was achieved for raw, undigested urine samples using a 10 ml sample volume. The reproducibility of the method was demonstrated by recovery measurements performed on urine that had been collected from several non-exposed volunteers and spiked with Pu. Tl-205 and Lu-175 were used as an internal standard and yield tracer, respectively. The method provides a rapid (similar to 11 min) means of measuring Pu in urine with no off-line sample pre-treatment, at levels below the regulatory requirements for drinking water.