Millions of people worldwide are affected by naturally occurring arsenic in groundwater. The development of a low-cost, highly sensitive, portable assay for rapid field detection of arsenic in water is important to identify areas for safe wells and to help prioritize testing. Herein, a novel paper-based fluorescence assay was developed for the on-site analysis of arsenic, which was constructed by the solid-phase fluorescence filter effect (SPFFE) of AsH-induced the generation of silver nanoparticles (AgNPs) toward carbon dots. The proposed SPFFE-based assay achieves a low arsenic detection limit of 0.36 μg/L due to the efficient reduction of Ag by AsH and the high molar extinction coefficient of AgNPs. In conjunction with a smartphone and an integrated sample processing and sensing platform, field-sensitive detection of arsenic could be achieved. The accuracy of the portable assay was validated by successfully analyzing surface and groundwater samples, with no significant difference from the results obtained through mass spectrometry. Compared to other methods for arsenic analysis, this developed system offers excellent sensitivity, portability, and low cost. It holds promising potential for on-site analysis of arsenic in groundwater to identify safe well locations and quickly obtain output from the global map of groundwater arsenic.

中文翻译：

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基于银纳米粒子形成固相荧光滤光效应的砷现场检测试剂盒

全世界有数百万人受到地下水中自然存在的砷的影响。开发一种低成本、高灵敏度、便携式的快速现场检测水中砷的方法对于确定安全井区域并帮助确定测试的优先顺序非常重要。在此，开发了一种用于现场分析砷的新型纸基荧光测定法，该测定法是通过AsH的固相荧光滤光效应（SPFFE）诱导银纳米颗粒（AgNP）向碳点的生成而构建的。由于 AsH 有效还原 Ag 以及 AgNP 的高摩尔消光系数，所提出的基于 SPFFE 的检测方法实现了 0.36 μg/L 的低砷检测限。与智能手机和集成样品处理和传感平台相结合，可以实现砷的现场敏感检测。通过成功分析地表水和地下水样本，验证了便携式测定的准确性，与通过质谱获得的结果没有显着差异。与其他砷分析方法相比，该开发的系统具有出色的灵敏度、便携性和低成本。它在地下水砷的现场分析方面具有广阔的前景，可以确定安全的井位并快速从全球地下水砷地图中获取输出。