Conjugated polymer microspheres for "turn-off"/"turn-on" fluorescence optosensing of inorganic ions in aqueous media.

The synthesis and characterization of a novel water-compatible microsized material, based on fluorescent conjugated polymers (CPs), and its applicability for optical sensing of inorganic ions of environment interest (copper and cyanide) in water media is here described. Polyfluorene-based fluorescent CPs were synthesized and functionalized with imidazole moieties (selective recognition element) and a terminal double bond (covalently linked to an organic matrix) through a postfunctionalization strategy. Further, microspheres of the novel imidazole-functionalized fluorescent CPs, able to work in water media, were synthesized via a microemulsion and polymerization procedure. The synthesized imidazole-functionalized CP microspheres were then evaluated as fluorescence “turn-Off” sensing materials for Cu2+ detection in aqueous media. Analyte detection was based on the quenching effect of the Cu2+, selectively recognized by the imidazole group, on the polymer fluorescence emission. The developed optosensor exhib...