糞便サンプル中の237Npの生物検定法

Fecal radiobioassay is a crucial and sensitive tool for estimating internal exposure and intake of actinides following radioactive or nuclear incidents. This study developed an analytical method to determine^²³⁷Np in feces, utilizing TEVA resin for separation and purification, followed by detection with inductively coupled plasma mass spectrometry (ICP-MS). By introducing^²⁴²Pu as a chemical homologue tracer, which shares similar chemical behavior with^²³⁷Np in the tetravalent state, we effectively monitored the chemical recovery of the target nuclide. We systematically optimized sample pretreatment steps, such as calcination temperature and redox conditions, along with key parameters in the TEVA resin separation process, including sample acidity and elution volume, significantly enhancing the separation and purification efficiency of^²³⁷Np. Experimental results indicated average chemical recoveries of 79% for^²³⁷Np and 82% for^²⁴²Pu. Furthermore, multiple repeated experiments effectively verified the method's accuracy and reliability. The established analytical procedure is practical and yields stable results, providing robust technical support for accurately quantifying^²³⁷Np in feces, with significant applications in radiation protection and public health monitoring.