A bioassay method for²³⁷Np in fecal samples.

Area of Science:

• Environmental Science
• Analytical Chemistry
• Nuclear Science

Background:

• Fecal radiobioassay is essential for internal actinide exposure assessment.
• Accurate quantification of neptunium-237 (²³⁷Np) in biological samples is critical for radiation protection.

Purpose of the Study:

• To develop and validate a robust analytical method for determining ²³⁷Np in human feces.
• To optimize sample pretreatment and separation techniques for enhanced efficiency and accuracy.

Main Methods:

• Utilized TEVA resin for selective separation and purification of ²³⁷Np.
• Employed Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for sensitive detection.
• Introduced ²⁴²Pu as a chemical homologue tracer to monitor recovery.

Main Results:

• Optimized calcination temperature, redox conditions, sample acidity, and elution volume for TEVA resin separation.
• Achieved average chemical recoveries of 79% for ²³⁷Np and 82% for ²⁴²Pu.
• Demonstrated method's accuracy and reliability through repeated experiments.

Conclusions:

• The developed analytical procedure is practical, stable, and provides accurate quantification of ²³⁷Np in feces.
• This method offers robust technical support for radiation protection and public health monitoring following radioactive incidents.