TcO4 ----> Tc4+ (reduction; gain = 3e)
Sn2+ ----> Sn4+ (oxidation; loss = 2e)
Pertechnetate is the oxidizing agent; stannous ion is the reducing agent. In the presence of a chelating agent (a compound with electronegative character that is capable of binding radiometal cations), the metal ion is tightly bound in the center of the octahedral structure
Other methods are useful in formation of Tc-99m compounds. In addition, special procedures are availkable for preparation of Tc-99m RBC's
