Monitoring acetylcholinesterase (AChE) is crucial in clinical diagnosis and drug screening. Traditional methods for detecting AChE usually require the addition of intermediates like acetylthiocholine, which complicates the detection process and introduces interference risks. Herein, we develop a direct colorimetric assay based on alkaline iron formate nanosheets (Fe(HCOO)(OH)·HO NSs, Fef NSs) for the detection of AChE without any intermediates. The as-prepared Fef NSs exhibit oxidase-like activity, catalyzing the generation of O, O and OH, which leads to a color change from colorless to blue when exposed to 3,3′,5,5′-tetramethylbenzidine. AChE directly inhibits the oxidase-like activity of Fef NSs, resulting in a hindered color reaction, enabling the detection of AChE. The biosensor has a linear detection range of 0.1–30 mU/mL, with a minimum detection limit of 0.0083 mU/mL (S/N = 3), representing a 100-fold improvement in detection sensitivity over the traditional Ellman's method. Satisfactory results were obtained when analyzing real AChE samples. Attractively, a method for the quantitative detection of AChE by a smartphone is established based on the Fef NSs. This method enables instant acquisition of AChE concentrations, achieving real-time visualized detection.

中文翻译：

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Fe(HCOO)2.6(OH)0.3 直接检测乙酰胆碱酯酶。在智能手机平台上具有氧化酶样活性的 H2O 纳米片

监测乙酰胆碱酯酶（AChE）对于临床诊断和药物筛选至关重要。传统检测AChE的方法通常需要添加乙酰硫代胆碱等中间体，这使得检测过程变得复杂并引入干扰风险。在此，我们开发了一种基于碱性甲酸铁纳米片（Fe(HCOO)(OH)·HO NSs，Fef NSs）的直接比色测定法，用于检测AChE，无需任何中间体。所制备的 Fef NS 表现出类似氧化酶的活性，催化 O、O 和 OH 的生成，当暴露于 3,3',5,5'-四甲基联苯胺时，颜色会从无色变为蓝色。 AChE 直接抑制 Fef NS 的氧化酶样活性，导致显色反应受阻，从而实现 AChE 的检测。该生物传感器的线性检测范围为0.1~30 mU/mL，最低检测限为0.0083 mU/mL（S/N = 3），检测灵敏度比传统Ellman方法提高了100倍。分析真实的 AChE 样品时获得了令人满意的结果。引人注目的是，基于 Fef NS 建立了一种通过智能手机定量检测 AChE 的方法。该方法能够即时获取AChE浓度，实现实时可视化检测。