en Radiation Biology Radiation Biology تحقيق بديع Original Research <p> </p><p class="MsoNormal" style="DIRECTION: rtl unicode-bidi: embed TEXT-ALIGN: center mso-pagination: none"><span dir="ltr" style="FONT-WEIGHT: bold COLOR: black DIRECTION: ltr unicode-bidi: embed language: EN-GB mso-ansi-language: EN-GB">ABSTRACT</span></p><p></p><p class="MsoNormal" style="TEXT-JUSTIFY: kashida TEXT-KASHIDA-SPACE: 80% TEXT-ALIGN: justify mso-pagination: none"><span style="FONT-WEIGHT: bold COLOR: black language: EN-GB mso-ansi-language: EN-GB">Backgrounds:</span><span style="COLOR: black language: EN-GB mso-ansi-language: EN-GB"> MD-55-2 is one of the Radiochromic film models with the sensitivity suitable for dose measurements ranging from 5 to 100 Gy.<span style="mso-spacerun: yes">  </span>However, this lower limit makes the film impractical for its applications in many areas such as brachytherapy source dosimetry.</span></p><p></p><p class="MsoNormal" style="TEXT-JUSTIFY: kashida TEXT-KASHIDA-SPACE: 80% TEXT-ALIGN: justify mso-pagination: none"><span style="FONT-WEIGHT: bold COLOR: black language: EN-GB mso-ansi-language: EN-GB">Materials and methods:</span><span style="COLOR: black language: EN-GB mso-ansi-language: EN-GB"> In this project, the useful range of the film has been extended by using a multilayer film technique. In this technique, single-, double-, and triple- layers of films were exposed to the doses ranging from 0.5 to 10 Gy using a Co-60 photon beam. Calibration curves for corresponding layers of films were obtained with a spectrophotometer using a 680nm wavelength.</span></p><p></p><p class="MsoNormal" style="TEXT-JUSTIFY: kashida TEXT-KASHIDA-SPACE: 80% TEXT-ALIGN: justify mso-pagination: none"><span style="FONT-WEIGHT: bold COLOR: black language: EN-GB mso-ansi-language: EN-GB">Results:</span><span style="COLOR: black language: EN-GB mso-ansi-language: EN-GB"> The results indicated that the sensitivities of double and triple layers were approximately 200% and 300%, respectively, higher than a single-layer film.<span style="mso-spacerun: yes">  </span>The impact of multilayer film arrangement on the energy dependence of the MD-55-2 Radiochromic film has also been examined using 100KVp, 80 KVp, and 6 MV X-ray beams. The results indicated an insignificant (within 5%) change in film responses with the beam energy. </span></p><p></p><p class="MsoNormal" style="TEXT-JUSTIFY: kashida TEXT-KASHIDA-SPACE: 80% TEXT-ALIGN: justify mso-pagination: none"><span style="FONT-WEIGHT: bold COLOR: black language: EN-GB mso-ansi-language: EN-GB">Conclusion:</span><span style="COLOR: black language: EN-GB mso-ansi-language: EN-GB"> Therefore, the multilayer technique enhances the Radiochromic film sensitivity and expands its application to the low dose range in field of brachytherapy source dosimetry.<span style="mso-spacerun: yes">  </span></span></p><p></p><p class="MsoNormal" style="DIRECTION: rtl unicode-bidi: embed TEXT-ALIGN: right mso-pagination: none"><span dir="ltr" style="DIRECTION: ltr FONT-FAMILY: "> </span></p><p></p> 11 16 http://ijrr.com/browse.php?a_code=A-10-1-111&slc_lang=en&sid=1 H. Pourbeigi hpour_ir@yahoo.com 79003194753284600330 79003194753284600330 Yes A.S. Meigooni 79003194753284600331 79003194753284600331 No H. Ghafourian 79003194753284600332 79003194753284600332 No R.A. Koona 79003194753284600333 79003194753284600333 No M.H. Zahmatkesh 79003194753284600334 79003194753284600334 No