Given the importance of food safety, it is highly desirable to develop a convenient, low-cost, and practical sensor for organophosphorus pesticides (OPs) detection. Here, a fluorescent paper analytical device (FPAD) based on aggregation-induced emission (AIE) nanoparticles (PTDNPs-0.10) and two-dimension MnO₂ nanoflakes (2D-MnNFs) was developed for instrument-free and naked-eye analysis of OPs. PTDNP-MnNFs composites were obtained through 2D-MnNFs and PTDNPs-0.10 by electrostatic interaction and the fluorescence emission of PTDNPs-0.10 was quenched through fluorescence resonance energy transfer (FRET). When acetylcholinesterase (AChE) was present, acetylthiocholine (ATCh) was catalytically hydrolyzed into thiocholine, which reduced MnO₂ of PTDNP-MnNFs into Mn²⁺, subsequently blocking the FRET and enhancing the fluorescence. Upon the addition of OP, AChE activity was depressed and thus the FRET between 2D-MnNFs and PTDNPs-0.10 was not affected, resulting in a slight change in fluorescence. On the basis of the variation in fluorescence intensity, highly sensitive detection of OP was readily achieved with a detection limit of 0.027 ng/mL; on the basis of the variation in brightness of FPAD, instrument-free and visual detection of OP was realized using a smartphone with a detection limit of 0.73 ng/mL. The application of FPAD has significantly simplified the detection procedure and decreased the test cost, supplying a new approach for on-site detection of OPs.

考虑到食品安全的重要性，迫切需要开发一种方便，低成本且实用的有机磷农药（OPs）检测传感器。在这里，开发了一种基于聚集诱导发射（AIE）纳米颗粒（PTDNPs-0.10）和二维MnO ₂纳米薄片（2D-MnNFs）的荧光纸分析装置（FPAD），用于对OPs进行无仪器和肉眼分析。通过2D-MnNFs和PTDNPs-0.10通过静电相互作用获得PTDNP-MnNFs复合材料，并通过荧光共振能量转移（FRET）淬灭PTDNPs-0.10的荧光发射。存在乙酰胆碱酯酶（AChE）时，乙酰硫胆碱（ATCh）催化水解为硫胆碱，从而将PTDNP-MnNFs的MnO ₂还原为Mn ²⁺，随后阻止FRET并增强荧光。加入OP后，AChE活性降低，因此2D-MnNFs和PTDNPs-0.10之间的FRET不受影响，导致荧光略有变化。根据荧光强度的变化，可以轻松实现OP的高灵敏度检测，检测限为0.027 ng / mL；根据FPAD亮度的变化，使用检测限为0.73 ng / mL的智能手机实现了OP的无仪器和目视检测。FPAD的应用大大简化了检测程序，降低了测试成本，为OP的现场检测提供了一种新方法。