基于聚乙烯亚胺稳定的荧光聚多巴胺/Fe2+的开-关型荧光传感技术检测草甘膦OA

As a widely used broad-spectrum herbicide worldwide,glyphosate(GLY)residues in the ecological environment and agricultural products pose potential threats to human health.Therefore,development of efficient and sensitive detection methods for GLY is of great significance.In this study,a novel"on-off"fluorescence sensor for GLY detection was developed based on the interaction among polyethyleneimine-stabilized fluorescent polydopamine(PEI-PDA),ferrous ion(Fe2+),and GLY.The prepared PEI-PDA exhibited green fluorescence emission at 530 nm.The fluorescence of PEI-PDA was slightly quenched by Fe2+through dynamic quenching,and the subsequent addition of GLY further diminished the fluorescence intensity.Under optimized conditions,the sensor exhibited a linear response to GLY concentration in the range of 0.5-500 μmol/L,with a limit of detection(S/N=3)of 0.64 μmol/L.The proposed method had high sensitivity,excellent specificity,and rapid response.The spiked recoveries in real sample analysis ranged from 88.03%to 105.44%,providing a simple and reliable novel sensing strategy for detection of GLY in the environment.