PREPARATION OF A CHEMICALLY CHARACTERIZED PENICILLAMINE-TC-99M COMPLEX

Abstract

In the reaction labeling penicillamine with 99mTc, several different chemical states of 99mTc were observed to occur with slight changes in the labeling conditions, such as the concentrations of penicillamine, 99mTcO4-, SnCl2 and H ion. The effects of these conditions were studied on the formation of the monomer complex, complex I, in which 99mTc is coordinated with the penicillamine as 99mTcO+2. Complex I formation competes with 99mTcO+2 hydrolysis, which leads to other 99mTc complexes. On this basis, the specific labeling conditions for complex I formation were established. Highly reproducible in vivo behavior in mice and rats was obtained with this chemically controlled complex I.