Spirobifluorene-based dyes: an old core for supramolecular application

Since the first synthesis of the spirobifluorene core in 1930, spirobifluorene-based molecules have been applied in several technological fields due to their chemical stability and versatility, especially in past few years.[1] For example, our group investigated the electrochemiluminescent properties of novel high emitting spirobifluorene-based molecules.[2,3] However, the use of spirobifluorene derivatives in water as well as onto surface is very limited.[4] In this communication, we present novel application for highly emitting spirobifluorene derivatives in aqueous solution as well as in solid state. In particular, the incorporation of the hydrophobic dye in bilayer membrane allowed obtaining fluorescent beta-cyclodextrin vescicles as host-guest model to investigate quenching and recognition processes in water.[5] Besides, a suitable chemical modification allowed solubilizing spirobifluorene in aqueous solution for the first time and using for supramolecular detection of protein in nanomolar scale.[6] Finally, self-assembled monolayers of spirobifluorene derivatives covalently bound to electrode surface permit controlling the orientation of the molecules onto surface.[7]