The behavior of neutral amine oxime chelates labelled with Tc at tracer level.

Neutral 99mTc-chelates were formed with propylene amine oxime, 3,3'-(1,3-propanediyldiimino)bis-(3-methyl-2-butanone)-dioxime and other PnAO analogues. Even though the other amine oxime ligands form neutral chelates with 99mTc, the stability, lipophilic and the brain uptake characteristics are less desirable than [99mTc]-PnAO. These results demonstrate that slight modifications in the amine oxime ligand backbone produces significant effects on the chemical and biological behavior of the [99mTc]dioxime chelates.