Diketopyrrolopyrrole-based fluorescent conjugated polymer for application of sensing fluoride ion and bioimaging

Diketopyrrolopyrrole (DPP)-based polymer (P1) was designed as the conjugated amplifying polymer for sensing fluoride ion and bioimaging. The delocalized electronic structure of this polymer was composed by copolymerization of DPP and fluorene monomers in the main chain. Some unalkylation imide moieties in DPP monomer (1) offered emission traps for the excited state (exciton) transport. Fluoride ion was induced as quencher to interrupt electronic energy transfer (EET) by strong deprotonated interaction. The obvious quenching of fluorescence and red-to-purple color change shows P1 can act as the great promise sensor for the detection of fluoride ion. Furthermore, P1 was fabricated to polymeric nanoparticles for bioimaging. This report provides a feasible way to construct the useful fluorescent sensing and bioimaging materials. (C) 2014 Elsevier B.V. All rights reserved.