Rapid analytical method of 90 Sr in urine sample: Rapid separation of Sr by phosphate co-precipitation and extraction chromatography, followed by determination by triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS)

• Published in: Applied radiation and isotopes 2019-08, Vol.150, p.103
• Main Authors: Tomita, Jumpei, Takeuchi, Erina
• Format: Article
• Language: English
• Subjects: Chemical Precipitation; Chromatography; Humans; Japan; Limit of Detection; Occupational Exposure - analysis; Phosphates; Radiation Exposure - analysis; Radiometry - methods; Strontium Radioisotopes - isolation & purification; Strontium Radioisotopes - toxicity; Strontium Radioisotopes - urine; Tandem Mass Spectrometry - methods
• ISSN: 1872-9800
• DOI: 10.1016/j.apradiso.2019.05.026

A rapid analytical method for determining Sr in urine samples (1-2 L) was developed to assess the internal exposure of workers in a radiological emergency. Strontium in a urine sample was rapidly separated by phosphate co-precipitation, followed by extraction chromatography, and the Sr activity was determined by triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). Measurement in the MS/MS mode with an O reaction gas flow rate 1 mL min showed no tailing of Sr at m/z = 90 up to 50 mg L Sr. The interferences of Ge, Se and Zr at m/z = 90 were successfully removed by phosphate co-precipitation, followed by extraction chromatography with a tandem column of Pre-filter, TRU and Sr resin. This analytical method was validated by the results of the analyses of synthetic urine samples (1.2-1.6 L) containing a known amount of Sr along with 1 mg of each of Ge, Se, Sr and Zr. The turnaround time for Sr purification from the urine sample and the Sr measurement by ICP-MS/MS was about 10 h. The detection limit of Sr was approximately 1 Bq per urine sample, which was lower than 15 Bq per urine after a day of intake giving 5 mSv of unplanned exposure of worker limited by Nuclear Regulation Authority of Japan.