Preparation and Application of Novel Fluorescence Chemical Sensor for Determining Trace Levels of Picronitric Acid Based on Water Soluble Conjugated Polymer

A water soluble conjugated polymer{poly[2, 5-bis(sodium 4-oxybutyrate)-1, 4-phenylethyny-lene-alt-1, 4-phenyleneethynylene], PPE-OBS}, was synthesized for the detection of picronitric acid(PA). PPE-OBS was characterized by means of mass spectrometry, NMR spectroscopy, infrared spectroscopy(IR), and so on. The experiment conditions and detection performance of PPE-OBS were systematically studied. The results show that the fluorescent quenching of PPE-OBS is the most efficient when the reaction time between PPE-OBS and PA is 20 min in the boric acid-sodium hydroxide buffer solution(pH=9.5). The results demonstrate that PPE-OBS as a sensor for PA has a good linear range from 1.0 to 60 μmol/L with the calculated limit of detection(LOD) to be 0.831 μmol/L. Meanwhile, PPE-OBS paper was applied to rapidly detecting PA in environmental water samples.