Calibration and evaluation of the MTS-N dosimeter for absorbed dose measurement in blood components

The use of ionizing radiation has significantly expanded, particularly in the healthcare sector, where the irradiation of blood components prevents transfusion-associated graft-versus-host disease (TA-GvHD). The ISO ASTM 51939:2017 standard establishes a minimum dose of 25 Gy for this procedure, requiring a precise and traceable dosimetric system. This study investigates the calibration of MTS-N thermoluminescent dosimeters at the Gamma Irradiation Laboratory (LIG) of CDTN, which currently uses radiochromic films for routine dosimetry. The dosimeters were calibrated using a RISØ TL/OSL DA-20 reader, and the results indicated that doses above 5 Gy caused reader saturation, distorting the TL emission curve. The introduction of attenuating filters maintained linearity up to 25 Gy, and the calibration coefficient was determined as 6.774×10⁻⁷ Gy/Count, confirming the system’s suitability for dosimetry in blood irradiation at LIG/CDTN.