Highly sensitive and selective chemosensors for d-fructose based on electrostatic interaction in aqueous solution

Anionic water-soluble polyfluorene (PBPSO3Na) and cationic boronic acid functional viologens (BBVs) were synthesized and combined into three new two-component chemosensors of d-monosaccharides, respectively. The sensing abilities of the three chemosensors for detection of d-monosaccharides were determined by fluorescence in a pH 7.4 buffer solution. The results show that o-BBV/PBPSO3Na and m-BBV/PBPSO3Na ensembles both have high selectivity and sensitivity for d-fructose with reversible “on–off” fluorescence responses. Due to different substituted positions of boronic acid groups in BBVs and electrostatic interactions of three BBVs with PBPSO3Na, the sensing order to d-fructose is m-BBV/PBPSO3Na > o-BBV/PBPSO3Na > p-BBV/PBPSO3Na.