Improved Method for Gamma Irradiation of Donor Tissue

Performance of cooling materials and their composites in maintaining freezing temperature during irradiation and transportation of bone allografts

“…1 Dry ice (DI) is the most common cooling material used for packaging. [3][4][5] Bones at UMMC Bone Bank are stored in À80 C deep freezers. During transportation and irradiation process, bones are maintained below À40 C by packing the bones in 20 kg DI in a polystyrene box.…”

“…Maintaining frozen temperature is required throughout sterilization process to minimize detrimental effects of radiation on biomechanical properties due to free radical formation through indirect effects of radiation. 4,[6][7][8][9] Hamer et al 10 found that femur rings irradiated at À78 C on DI were less brittle due to less collagen damage as compared to bones irradiated at room temperature. Eagle et al 11 kept tissues at a low temperature of À79 C in 15 kg DI in polystyrene-insulated transport boxes during the transport to and from the gamma facility.…”

“…In addition, thermally insulated packaging can maintain product temperatures within acceptable ranges thus slow down the deterioration of the product in the distribution environment until it reaches the consumer. 19 Although DI is the common cooling material for maintaining bones in frozen state throughout irradiation process or during long-distance and overseas dispatch, 4,20,21 it is a conundrum and an uphill task especially when the cost of DI keeps increasing and there were times when supply of DI was limited or not available in some parts of Malaysia.…”