Although methods based on mass spectrometry or immunoassays can meet the demands of paraquat detection, their application is limited by a lack of convenience or stability. Herein, a facile visual aptamer-based chromatographic strip (CS) was fabricated for the rapid paraquat detection using the cationic polyelectrolyte poly(diallyl dimethyl ammonium chloride) (PDDA) as a powerful capture molecule at test-line (T-line). The PDDA could capture the gold nanoparticles (AuNPs) through strong electrostatic interactions for visual detection. The proposed CS showed an excellent response for paraquat in the range of 20–150 μg·L⁻¹, and the limit of detection (LOD) was as low as 4.28 μg·L⁻¹. This detection method has good stability and specific selectivity, and can visually determine paraquat residues more than 30 μg·L⁻¹ by naked eye within 3 min. The results demonstrated that the prepared CS based on aptamer and cationic polyelectrolyte is an accurate and practicable tool for rapid analysis of pesticide residues.

虽然基于质谱或免疫分析的方法可以满足百草枯检测的需求，但它们的应用受限于缺乏便利性或稳定性。在此，使用阳离子聚电解质聚（二烯丙基二甲基氯化铵）（PDDA）作为测试线（T线）的强大捕获分子，制造了一种简便的基于适配体的可视化色谱条（CS），用于快速检测百草枯。PDDA 可以通过强静电相互作用捕获金纳米颗粒 (AuNPs) 以进行视觉检测。^{所提出的 CS 在 20-150 μg·L -1}范围内对百草枯表现出优异的响应，检测限 (LOD) 低至 4.28 μg·L ^-1. 该检测方法具有良好的稳定性和特异性选择性，可在3 min内用肉眼目测30 μg·L ^{-1以上的百草枯残留量。}结果表明，基于适配体和阳离子聚电解质制备的CS是一种准确、实用的农药残留快速分析工具。