DCDAPH (1,1-dicyano-6-(4-N,N-dimethylaminophenyl)-1,3,5-hexatriene) is a far-red fluorescent probe that has proved to have affinity to Aβ plaques. It has been used for fluorescent staining of brain sections, as well as in vivo detection of Aβ1-42 aggregates by small animal near-IR imaging.