Q-band EPR biodosimetry in tooth enamel microsamples: feasibility test and comparison with x-band.
A comparative study of electron paramagnetic resonance dosimetry in Q- and X-bands has shown that Q-band is able to provide accurate measurements of radiation doses even below 0.5 Gy with tooth enamel samples as small as 2 mg. The optimal amount of tooth enamel for dose measurements in Q-band was found to be 4 mg. This is less than 1% of the total amount of tooth enamel in one molar tooth. Such a small amount of tooth enamel can be harmlessly obtained in an emergency requiring after-the-fact radiation dose measurement. The other important advantage of Q-band is full resolution of the radiation-induced EPR signal from the native, background signal. This separation makes dose response measurements much easier in comparison to conventional X-band measurements in which these overlapping signals necessitate special methods for doses below 0.5 Gy. The main disadvantages of Q-band measurements are a higher level of noise and lower spectral reproducibility than in X-band. The effect of these negative factors on the precision of dose measurements in Q-band could probably be reduced by improvement of sample fixation in the resonance cavity and better optimization of signal filtration to reduce high-frequency noise.
Romanyukha
A
A
Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA. aromanyukha@usuhs.mil
Mitchell
C A
CA
Schauer
D A
DA
Romanyukha
L
L
Swartz
H M
HM
D003743:Dental Enamel; D004578:Electron Spin Resonance Spectroscopy; D005240:Feasibility Studies; D006801:Humans; D008963:Molar; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*