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

Abstract

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 × 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 × 10⁻⁷ mol L⁻¹, making P2 a novel, sensitive and selective cyanide probe.