Effect of gamma-radiation on the Sn(II) content,radiochemical purity,in-vitro stability and biological distribution of some99mTc-labelled freeze dried kits

Gamma-irradiation can be used for the sterilization of some^99mTc-labelled freeze dried kits. In connection with this the effect of -radiation on Sn(II) content, radiochemical purity,in-vitro stability and biological distribution of some currently used^99mTc-labelled kits has been investigated. For irradiation the certain radiation sterilization doses (25 and 50 kGy) were used. A variable decrease of Sn(II) content was observed in all -irradiated kits. The losses are in the order of 10–25% compared with the Sn(II) content of original ones. The colour of the irradiated kits did not changed except DTPA which developed yellow colour after irradiation. For the irradiated and original kits nearly the same pH were found. The irradiated kits seemed to undergo partial decomposition or chemical alteration which led to some deviation of the biological distribution of them.