In this work, boron carbon oxynitride quantum dots (BCNO QDs) were prepared by a one-step hydrothermal process of ethanolamine and boric acid. BCNO QDs exhibited blue fluorescence with the optimal excitation/emission fluorescence peak at 335 and 420 nm, respectively. As an efficient fluorescence quencher, manganese dioxide (MnO₂) nanosheets can effectively quench the fluorescence of BCNO QDs via the inner filter effect (IFE). Acetylcholinesterase (AChE) catalyzes the hydrolysis of acetylcholine (ATCh) to produce thiocholine (TCh). TCh can reductively degrade MnO₂ nanosheets to generate Mn²⁺, thereby recovering the fluorescence of BCNO QDs. Organophosphorus pesticides (OPs) can inhibit the activity of AChE enzymes, thereby preventing the production of TCh and the decomposition of MnO₂ nanosheets, resulting in the fluorescence “turn-off”. Therefore, the concentration of OPs can be detected by measuring the fluorescence intensity change of AChE-ATCh-MnO₂-BCNO-QDs system. Under optimal experimental conditions, the dynamic detection range of paraoxon is 0.1–250 ng mL⁻¹, and the detection limit is 0.03 ng mL⁻¹. Meanwhile, the reaction system also showed concentration-dependent visual color changes from colorless to brownish. Furthermore, we prepared a portable BCNO QDs test paper. By using a smartphone to identify the RGB values of the reaction solution and the corresponding test paper, we carried out the digital image chromaticity analysis, which can shorten the detection time and reduce the detection cost, and provide an effective solution for the rapid detection of OPs on site.

在这项工作中，硼碳氮氧化物量子点（BCNO QDs）是通过乙醇胺和硼酸的一步水热法制备的。BCNO QD 呈现蓝色荧光，最佳激发/发射荧光峰分别位于 335 和 420 nm。作为一种高效的荧光猝灭剂，二氧化锰 (MnO ₂ ) 纳米片可以通过内过滤效应 (IFE) 有效地猝灭 BCNO QDs 的荧光。乙酰胆碱酯酶 (AChE) 催化乙酰胆碱 (ATCh) 水解生成硫代胆碱 (TCh)。TCh 可以还原降解 MnO ₂纳米片以生成 Mn ²⁺，从而恢复 BCNO QD 的荧光。有机磷农药 (OPs) 可以抑制 AChE 酶的活性，从而阻止 TCh 的产生和 MnO ₂纳米片的分解，从而导致荧光“关闭”。因此，可以通过测量AChE-ATCh-MnO ₂ -BCNO-QDs系统的荧光强度变化来检测OPs的浓度。在最佳实验条件下，对氧磷的动态检测范围为0.1-250 ng mL ^-1，检测限为0.03 ng mL ^-1. 同时，反应体系也表现出浓度依赖性的视觉颜色从无色到褐色的变化。此外，我们准备了便携式 BCNO QDs 试纸。通过使用智能手机识别反应液和相应试纸的RGB值，进行数字图像色度分析，可以缩短检测时间，降低检测成本，为快速检测试剂盒提供有效的解决方案。 OP 现场。