A new polyfluorene bearing pyridine moieties: a sensitive fluorescent chemosensor for metal ions and cyanide

To develop sensitive and selective CN- chemosensors, a new polyfluorene (P2) bearing pyridine moieties was designed and obtained conveniently, the fluorescence of which could be completely quenched by Cu2+ ions at the concentration as low as 5.67 x 10(-7) mol L-1 in diluted solutions. By utilizing the much higher stability constant of the complex of CN- and Cu2+, the quenched fluorescence of the solution of P2 by Cu2+ ions could recover upon the addition of trace CN- anions, with the detection limit as low as 3.3 x 10(-7) mol L-1, making P2 a novel, sensitive and selective cyanide probe.