The synthesis and characterization of [¹²⁴I]IMPY, a thioflavin-S derivative, in transgenic mouse models of Alzheimer's disease

6-[124I]iodo-2-(4′-N,N-dimethylamino)-phenylimidazo[1,2 -a]pyridine ([124I]IMPY) was synthesized and characterized as a positron-emitting probe to identify Alzheimer's disease in transgenic mouse models. A significant reduction in radioactivity retention in the hippocampus and frontal cortex by co-incubation with nonradioactive IMPY was observed. Highly specific retention of radioactivity in beta-amyloid-rich regions of brain sections was also noted. This study demonstrated that [124I]IMPY was a promising probe for the mouse model and may be useful for positron emission tomography to image beta-amyloid plaques in the human brain.