Toward a Highly Sensitive Fluorescence Sensing System of an Amphiphilic Molecular Rod: Facile Synthesis and Significant Solvent-Assisted Photophysical Tunability

  Macromolecules, 2011, 44 (4), 1009–1015

A conjugated polyelectrolyte with symmetrically assembled hydrophilic and hydrophobic side groups along the backbone has been successfully synthesized and demonstrated significant photophysical tunability with 65 nm of wavelength shift and 10-fold of intensity enhancement for the emission maximum, through solvent composition adjustment. The highest fluorescence quenching effect (I/I0 = 148) toward 10 μM of Fe3+ was achieved in the solution having a THF/H2O ratio of 30/70, which could be attributed to a delicate balance among the influencing factors for the fluorescence quenching systems, the initial fluorescence, the rate of energy migration, and the accessibility of the receptors. The amplified symmetrical aggregation?nonaggregation inversion and the asymmetrical cation sensitivity across the whole range of H2O/THF composition were consistent with the molecular design.