Fundamental investigation on sup(99m)Tc generator (Dynatec) developed recently

The sup(99m)Tc injection used for RI (radioisotope) angiography, which is one of the recent inspection methods in nuclear medicine, is required to be of high specific activity. With this situation, the facilities to use sup(99m)Tc generators seem to increase with increasing patients in future. Since the author has had a chance to use the 99Mo-sup(99m)Tc generator, Dynatec, lately developed by Dynabot RI Research Laboratory, the application experiences are described about the advantages of the generator, elution pattern, leakage dose rate and others. The Dynatec, different from the conventional Dynacow sup(99m)Tc kit, can elute the sup(99m)TcO4- of high specific activity with a small quantity of physiological sodium chloride solution, and enables to make milking simply in a short time. The feature of the Dynatec is the capability of obtaining solution of constant specific activity, because it can set the quantity of eluate at 15 ml, 10 ml and 5 ml. The leakage dose from the generator is as very small as 0.1 mR/hr at the distance of 1 m. However, it is preferable to carry out milking operation by employing the shield of lead or others to decrease radiation exposure for the operators. It is desirable that the processes from milking to labelling and subdivision into syringes are fully automated in the future. (Wakatsuki, Y.)