A pillar[5]arene-based three-component supramolecular copolymer for the fluorescence detection of spermine†

The supramolecular polymerization of a bis-pillar[5]arene dicarboxylic acid monomer () in the presence of a mixture of complementary bis-guests 1,12-dodecanediyl-bis-1,1′-1H-imidazole () and bis-N,N’-(6-(1H-imidazole)decyl)-perylene bisimide (), produces an AA/BB-type supramolecular copolymer // that retains the properties of the parent bi-component systems, that is, / solubility and / photoresponsiveness. The supramolecular copolymer showed stimuli-responsiveness, reacting to the presence of the cancer marker, spermine (), by disassemblying and releasing . Once released, the perylene bisimide monomer (quenched in the copolymer by host-to-guest electron transfer), showed a remarkable increase of emission intensity. ESI-MS data are fully consistent with the formation of the // copolymer, and AFM investigations on films cast from // and // + solutions demonstrated that the supramolecular copolymer sensing abilities are retained also in the solid state.