en Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;">Background: People occasionally undergo medical diagnostic X-ray examinations and expose their red blood cells to radiation. Radiation that is generated from medical diagnostic X-ray machines is widely used in medical diagnoses. One of the important parameters is kilo-voltage (kV) that is applied across the X-ray tube in medical diagnostic X-ray machines. Kilo-voltage influences the radiation dosage. The aim of this study is to determine the hemolysis, osmotic fragility, and fluorescence anisotropy value on irradiated red blood cells as a function of kV during medical diagnostic X-ray examinations. &nbsp;Materials and Methods: The kV, kilo-voltage that is applied across an&nbsp; X-ray tube, of a medical diagnostic X-ray machine was operated at 50, 70 and 100 kV. We determined the hemolysis, osmotic fragility, and fluorescence anisotropy value in red blood cells at 0.5 and 4 hours post-irradiation. In order to determine hemolysis and osmotic fragility, the release of hemoglobin was measured by spectrophotometry technique. 1,6-diphenyl-1,3,5-hexatriene (DPH) was used as a molecular probe for determining fluorescence anisotropy value by fluorescence anisotropy technique. Non-irradiated red blood cells served as the control. Results: For the 50, 70, and 100 kV of medical diagnostic X-rays, the hemolysis, osmotic fragility, and fluorescence anisotropy values of irradiated red blood cells at 0.5 and 4 hours post-irradiation did not significantly change when compared to the control.&nbsp; Conclusion: Our results suggested that 50, 70, and 100 kV of medical diagnostic X-ray did not influence hemolysis, osmotic fragility, and fluorescence anisotropy values of irradiated red blood cells.<br> &nbsp;</div> Medical diagnostic X-ray, red blood cell, hemolysis, osmotic fragility, fluorescence anisotropy. 123 127 http://ijrr.com/browse.php?a_code=A-10-1-710&slc_lang=en&sid=1 M. Tungjai mtungjai@gmail.com 7900319475328460015632 7900319475328460015632 Yes Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, 110 Intawaroroj Rd., Sripoom, Chiang Mai, 50200, Thailand N. Phathakanon 7900319475328460015633 7900319475328460015633 No Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, 110 Intawaroroj Rd., Sripoom, Chiang Mai, 50200, Thailand P. Ketnuam 7900319475328460015634 7900319475328460015634 No Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, 110 Intawaroroj Rd., Sripoom, Chiang Mai, 50200, Thailand J. Tinlapat 7900319475328460015635 7900319475328460015635 No Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, 110 Intawaroroj Rd., Sripoom, Chiang Mai, 50200, Thailand S. Kothan 7900319475328460015636 7900319475328460015636 No Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, 110 Intawaroroj Rd., Sripoom, Chiang Mai, 50200, Thailand