An alternative method using microwave power saturate in fingernail/electron paramagnetic resonance dosimetry

Area of Science:

• Radiation Dosimetry
• Biophysics
• Analytical Chemistry

Background:

• Electron paramagnetic resonance (EPR) is a technique used for radiation dosimetry.
• Conventional EPR dosimetry methods using fingernails can have limitations, especially at low radiation doses.
• Fingernail dosimetry offers a potential method for retrospective dose assessment due to its accessibility.

Purpose of the Study:

• To develop and validate an alternative EPR dosimetry method for fingernail samples.
• To improve the accuracy and reliability of EPR dosimetry at low radiation doses (0-3 Gy).
• To address limitations of conventional methods when applied to fingernail dosimetry.

Main Methods:

• A two-step method involving dehydration of fingernail clippings at 70 °C for 72 hours to reduce water content.
• Measurement and fitting of EPR signals at successive microwave power levels.
• Application of a novel 'curvature' value derived from EPR signal amplitudes for dosimetry.

Main Results:

• Dehydration significantly improved the variability of EPR signals in fingernail samples.
• The new method, utilizing the 'curvature' value, demonstrated validity for low-dose dosimetry (0-3 Gy).
• The method showed promise as an alternative for specific scenarios where conventional dosimetry is unsuitable.

Conclusions:

• The proposed dehydration and 'curvature' analysis method offers a viable alternative for fingernail EPR dosimetry at low radiation doses.
• This approach enhances the reliability of EPR dosimetry for retrospective assessment of low-level radiation exposure.
• The method provides a practical solution for situations where conventional fingernail dosimetry is not optimal.