Preparation and application of a highly sensitive conjugated polymer-copper (Ⅱ) composite fluorescent sensor for detecting hydrazine in aqueous solution

At first, a conjugated polymer (poly(2,5-bis(4-(bis(pyridin-2-ylmethyl)amino) butoxyl)-1,4-Phenylethynylene-1,4-poly(phenylene ethynylene), PPE-DPA) was synthesized based on our earlier report. In this work, a highly selective and sensitive composite fluorescent sensor (PPE-DPA-Cu²⁺), which was PPE-DPA complexed with copper ions, has been developed and used to measure trace amounts of hydrazine in environmental water samples. The experiment conditions were investigated. Under optimized conditions, the sensor shows satisfactory detection performance, which can highly sensitively detect hydrazine with a linear range of 0–70 nmol L⁻¹ and detection limit as low as 5.4 × 10⁻¹⁰ mol L⁻¹ (S/N = 3). Meanwhile, the sensor exhibits high selectivity and strong anti-interference ability for various cations, anions, common reducing agents and organic amines. This sensor has been applied to detect hydrazine in the real water samples, and the recovery of hydrazine was 92.3%–112.0% after added standard solution of hydrazine. Satisfactory results indicate that the sensor is expected to be utilized for quantitative detection of hydrazine in environmental samples.