School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei 230009, China.
School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei 230009, China.
J Hazard Mater. 2023 Jun 5;451:131171. doi: 10.1016/j.jhazmat.2023.131171. Epub 2023 Mar 7.
Engineering efficient dual-mode portable sensor with built-in cross reference correction is of great significance for onsite reliable and precise detection of organophosphorus pesticides (OPs) and evading the false-positive outputs, especially in emergency case. Currently, most nanozyme-based sensors for OPs monitoring primarily replied on the peroxidase-like activity, which involved unstable and toxic HO. In this scenario, a hybrid oxidase-like 2D fluorescence nanozyme (PtPdNPs@g-CN) was yielded by in situ growing PtPdNPs in the ultrathin two-dimensional (2D) graphitic carbon nitride (g-CN) nanosheet. When acetylcholinesterase (AChE) hydrolyzed acetylthiocholine (ATCh) to thiocholine (TCh), it ablated O• from the dissolved O catalyzed by PtPdNPs@g-CN's oxidase-like activity, hampering the oxidation of o-phenylenediamine (OPD) into 2,3-diaminophenothiazine (DAP). Consequently, with the increasing concentration of OPs which inhibited the blocking effect by inactivating AChE, the produced DAP caused an apparent color change and a dual-color ratiometric fluorescence change in the response system. Through integrating into a smartphone, a HO-free 2D nanozyme-based onsite colorimetric and fluorescence dual-mode visual imaging sensor for OPs was proposed with acceptable results in real samples, which holds vast promise for further development of commercial point-of-care testing platform in early warning and controlling of OPs pollution for safeguarding environmental health and food safety.
构建内置交叉参考校正的高效双通道便携式传感器对于现场可靠、精确检测有机磷农药（OPs）和避免假阳性结果具有重要意义，尤其是在紧急情况下。目前，大多数基于纳米酶的 OPs 监测传感器主要依赖于过氧化物酶样活性，其中涉及不稳定和有毒的 HO。在这种情况下，通过在超薄二维（2D）石墨相氮化碳（g-CN）纳米片中原位生长 PtPdNPs，生成了一种混合氧化酶样 2D 荧光纳米酶（PtPdNPs@g-CN）。当乙酰胆碱酯酶（AChE）水解乙酰硫代胆碱（ATCh）生成硫代胆碱（TCh）时，它会从 PtPdNPs@g-CN 的氧化酶样活性催化的溶解氧中消耗 O•，从而阻碍邻苯二胺（OPD）被氧化成 2,3-二氨基吩噻嗪（DAP）。因此，随着 OPs 浓度的增加，它会抑制 AChE 的失活作用，从而导致反应体系中产生的 DAP 引起明显的颜色变化和双通道比率荧光变化。通过集成到智能手机中，提出了一种无 HO 的 2D 纳米酶现场比色和荧光双通道可视化成像传感器，用于 OPs 的检测，在实际样品中取得了可接受的结果，为进一步开发用于环境健康和食品安全的 OPs 污染预警和控制的商业即时检测平台提供了广阔的前景。
