Generator-produced 99m TcO4-: carrier free.

A solution of 99m-TCO4-minus, as eluted from a 99Mo-99mTc radionuclide generator contains a greater chemical quantity of technetium than that attributable to the metastable isomer alone. The isomeric transition of the radionuclide of interest, 99mTc, gives rise to a determinable and chemically significant quantity of technetium carrier, 99Tc. A method is presented for calculating the total chemical quantity of technetium in a generator eluate.