Preparation of "no-carrier-added" technetium-99m complexes: Determination of the total technetium content of generator eluents

Abstract

The total concentration of pertechnetate in 99Mo/99mTc generator eluents can be readily determined by ion exchange HPLC with u.v. detection. Tracking of a 7450 mCi generator through its useful clinical life leads to values of [TcO4-] in the range 10-7-10-6M, and values of the ratio (moles total technetium)/(mCi 99mTc) in the range (3-35) × 10-12 mol/mCi. Trace amounts (ca. 0.01%) of non-pertechnetate, 99mTc-containing impurities are detected, and generators of one manufacturer yield eluents with a large number of u.v. absorbing impurities. The total concentration of pertechnetate in generator eluents is important in determining whether or not chemistry developed with macroscopic concentrations of 99Tc "carrier" can be translated to the "no-carrier-added" 99mTc level. Success or failure of this translation could depend on whether the reaction controlling product formation is first- or second-order in technetium concentration. © 1982.