There is a need for β-amyloid plaque (Aβ)-binding compounds that can be used for detecting plaques common in Alzheimer's Disease (AD).  The common dye, Congo Red, binds to Aβ[1].  It is proposed that certain Congo Red derivatives, such as (E,E)–1–fluoro–2,5–bis(3–hydroxycarbonyl–4–hydroxy)styrylbenzene (FSB), may be used for non-invasive detection of Aβ using ¹⁹F magnetic resonance imaging (MRI)[2]. 

      To enhance the intensity of the ¹⁹F MRI signals, we synthesized (E,E)–1,2,4,5–tetrafluoro–3,6–bis(3–hydroxycarbonyl–4–hydroxy)styrylbenzene(TFSB) as a  poly-fluorinated Aβ imaging ligand.  In addition to the tetrafluorophenyl core of the bis-stilbene skeleton, fluorine was also incorporated in the form of symmetrical trifluoromethyl groups.  We have shown that TFSB, along with several other bis-stilbene derivatives, bind specifically to Aβ plaques as demonstrated by in vitro staining of APP mouse brain sections.  We intend to study ¹⁹F MRI signal intensities using NMR and in vivo APP mouse models with MRI.  Through a systematic approach of fluorinated Aβ-binding ligand design and synthesis, a non-invasive probe for AD using ¹⁹F MRI may be developed.  This approach has promise not only to help detect AD in its early stages but also to allow study of the progression of the disease in patients.