摘要：In the radiolabelling process, the frequency of routine analytical testing must be defined with a risk assessment based on different factors (Pharmeuropa Vol. 26 No. 2, 5.19). Aim of this study is to define the criteria based on the risk assessment required for setting the frequency of analytical controls. 331 preparations of three different radiopharmaceuticals labeled with 99mTc were examined analyzing temporal trends of radiochemical purity values, potential correlation between radiochemical purity values and total radioactivity content of bulk as well as potential correlation between radiochemical purity values and radioactivity concentration of bulk. The analysis shows no direct correlation between percentage of radiochemical purity and total radioactivity content of preparation and between radiochemical purity values and radioactivity concentration in final bulk solution. Moreover, the routine analytical controls executed for one year on each preparation made it possible to determine how the analytical values do not have inter-operator dependency and there is no evidence of specific temporal trends over time. The study is aimed to assess any eventual criticality related with radiochemical purity tests, determine the possibility of a parametric release and the optimal frequency of tests, without reducing the level of safety of the preparations. This will produce a substantial reduction of costs and of radiation exposure to ionizing radiation of the staff dedicated to Quality Control procedures.
