Development of ^99mTc‐thioflavin‐T derivatives for detection of systemic amyloidosis

Abstract

Abstract In a search for a 99m Tc‐labelled tracer agent for imaging of amyloid plaques in patients with systemic amyloidosis (SA), we have conjugated three bifunctional chelating ligands, namely S ‐benzyl‐mercaptoacetyl‐l‐aspartyl(tBu)‐glycine, HYdrazinoNICotinic acid and nitrilotriacetic acid, to the 2‐phenylbenzothiazole core of thioflavin‐T (ThT), which has known affinity for amyloid. The compounds were successfully synthesized and labelled with technetium‐99m. Their structure was confirmed by radio‐LC‐MS analysis. After i.v. injection in normal mice, all three 99m Tc‐labelled ThT derivatives were excreted almost exclusively via liver and intestines. This indicates that the new tracer agents have not the required biokinetics for application as a probe for detection of SA in the abdominal region. Copyright © 2008 John Wiley & Sons, Ltd.