Li Chen, Liu Yuan, Guo Yiqing, Guo Wang, Zhang Xinai, Zhang Wen, Zou Xiaobo, Sun Zongbao
Department of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
Zhenjiang Institute for Food and Drug Control, Zhenjiang 212000, China.
Food Chem. 2025 Nov 15;492(Pt 1):145243. doi: 10.1016/j.foodchem.2025.145243. Epub 2025 Jun 26.
Although electrochemical sensors offer a convenient approach for cyanide detection, they often require multiple components or complex instrumentation. To address this limitation, we designed a covalent organic framework-encapsulated thionine-modified silver‑gold composite (Ag-Au@COF-Thi) sensor that integrates sensitivity and simplicity into a single platform. AgAu nanoparticles are embedded within a COF matrix, with Thi stably adsorbed on the Au surface to provide an internal reference. The sensor is integrated into a miniaturized electrochemical platform, enabling point-of-care cyanide detection via dual-signal readout: target (I) and reference (I). After each cycle, the sensor breaks down the silver-cyanide complex and restores the electrode surface, ensuring repeatable performance. Under optimal conditions, the I/ I signal ratio correlates linearly with cyanide concentration from 1 ng/mL to 0.5 μg/mL, achieving a detection limit of 0.82 ng/mL. This sensor effectively quantifies cyanide in Baijiu and fermented grains, offering a promising method for food contamination monitoring.
尽管电化学传感器为氰化物检测提供了一种便捷的方法，但它们通常需要多个组件或复杂的仪器设备。为了解决这一局限性，我们设计了一种共价有机框架封装的硫堇修饰银金复合材料（Ag-Au@COF-Thi）传感器，该传感器将灵敏度和简易性集成到了一个单一平台中。银金纳米颗粒嵌入在共价有机框架基质内，硫堇稳定吸附在金表面以提供内部参考。该传感器集成到一个小型化电化学平台中，通过双信号读出实现即时护理氰化物检测：目标信号（I）和参考信号（I）。每个循环后，传感器会分解银氰络合物并恢复电极表面，确保可重复的性能。在最佳条件下，I/I信号比与氰化物浓度在1 ng/mL至0.5 μg/mL范围内呈线性相关，检测限达到0.82 ng/mL。该传感器能有效定量白酒和发酵谷物中的氰化物，为食品污染监测提供了一种有前景的方法。
