Abstract In continuation of our investigation on the bithiophene structure as potential β- amyloid probes, a series of (E)-5-styryl-2, 2′-bithiophene (SBTP) derivatives was designed and synthesized. In vitro binding showed that all of them displayed high binding affinities to Aβ 1–42 aggregates (K i= 0.10–41.05 nM). Moreover, two radio-iodinated probes,[125 I]-(E)- 5-(4-iodostyryl)-2, 2′-bithiophene ([125 I] 8) and [125 I]-(E)-5-iodo-5′-(4-methoxystyryl)- ...