The use of 90Sr/90Y generator for electrochemical separation of 90Y from 90Sr

摘要

90Y is a radioisotope and decay product of 90Sr for therapeutic purpose due to its suitable half-life T1/2=64.1h. The half-life of 90Sr is longer (T1/2=28,9 years) and have a high skeleton uptake. To obtain a radionuclide with a high level of purity is necessary to separate 90Y from the bulk of 90Sr. The most promising approach to separate 90Y from the bulk of 90Sr is using the electrochemical 90Sr/90Y generator. udOur group is a part of the project for development of therapeutic radiopharmaceuticals based on 177Lu and 90Y labelled monoclonal antibodies and peptides. A significant step in development of those radiopharmaceuticals is separation of 90Y from the bulk of 90Sr. One part of the groupused an electrochemical 90Sr/90Y generator. The separation of 90Yfrom mixture of 90Sr and 90Y is based on the selective deposition of 90Y on a platinum electrode. This is attributed to the difference in electrode potential of Sr2+ and Y3+ ions in acidic media (90Sr have Eº = -2.89 V and 90Y have Eº = - 2.27 V). By controlled applications of potential can be achieved selectively electrodeposited of 90Y on the platinum cathode. This process of electrochemical separation involved two electrolysis cycles - the first for separation of 90Y from the bulk of 90Sr and the second for purification of 90Y. The first electrolysis was performed at pH 2-3, at a potential of -2.5 V using pure Pt as cathode and anode. The second electrolysis was performed at same conditions. The cathode from the first cycle containing 90Y was used for anode in the second step coupled with a circular platinum electrode as the cathode. During second cycle 90Y was leached from the platinum plate and was deposited on circular platinum cathode. udWe can conclude that electrochemical separation of 90Y from 90Sr with 90Sr/90Y generator is of high importance for radiopharmacy and for obtaining a pure 90Y, who can be used for radiolabeling of various targeting molecules for the treatment of cancer.ududud