Rapid determination of ultra-trace plutonium in large volume of urine samples by tandem quadrupole inductively coupled plasma-mass spectrometry

Abstract Rapid bioassay method for plutonium in urine samples are employed to assess the possible internal dose resulting from exposure to plutonium in the event of a radiological and nuclear emergency. In this work, a rapid method for the determination of plutonium isotopes (239Pu and 240Pu) in large volume of urine samples was developed using tandem quadrupole ICP-MS combined with a high-efficiency sample introduction system (APEX-Ω). The mixture gases of NH3 and He was employed to effectively eliminate the tailing of 238U and the uranium hydride ions (238U1H+and 238U1H2+) and significantly improve the measurement sensitivity of plutonium. The method was validated by analyzing urine samples spiked with known amounts of 239Pu and 240Pu ranging from 1 to 60 fg. The detection limits for the method were estimated to be 0.83 fg for 239Pu, 0.14 fg for 240Pu in 1 L of urine.