College of Chemistry and Chemical Engineering, Yunnan Normal University, Yunnan, Kunming 650092, PR China; Baoshan College of Traditional Chinese Medicine, Yunnan, Baoshan 678000, PR China.
College of Chemistry and Chemical Engineering, Yunnan Normal University, Yunnan, Kunming 650092, PR China.
Food Chem. 2025 Feb 1;464(Pt 1):141540. doi: 10.1016/j.foodchem.2024.141540. Epub 2024 Oct 5.
Ochratoxin A (OTA) poses significant risks to human health, being potentially nephrotoxic, carcinogenic, genotoxic, and immuno-toxic. In this work, we developed a dual-mode aptasensor for OTA analysis, integrating colorimetric, electrochemical, and smartphone-based detection. The bifunctional Fe-MIL-88 metal-organic framework, acting as both a nanozyme capable of catalyzing the 3,3',5,5'-tetramethylbenzidine substrate and an electrochemical signal amplifier, enabled OTA quantification through current response or changes in color and absorbance intensity. Besides, the spatial confinement effect enhances the local concentration of Fe-MIL-88 signal probes through rolling circle amplification reaction, thereby contributing to a substantial enhancement in sensitivity. The proposed technique is simple, disposable, highly sensitive and selective, enabling OTA detection in the range of 1 fg/mL to 250 ng/mL, with a limit of detection of 0.22 fg/mL (3σ rule). Furthermore, we successfully detected OTA in corn, wheat, and red wine samples, with results good concordance with those obtained using commercial enzyme-linked immunoassay kits.
赭曲霉毒素 A（OTA）对人类健康构成重大风险，具有潜在的肾毒性、致癌性、遗传毒性和免疫毒性。在这项工作中，我们开发了一种用于 OTA 分析的双模式适体传感器，集成了比色、电化学和基于智能手机的检测。双功能 Fe-MIL-88 金属有机骨架既可以作为一种纳米酶，能够催化 3,3',5,5'-四甲基联苯胺底物，也可以作为电化学信号放大器，通过电流响应或颜色和吸光度强度的变化来定量 OTA。此外，空间限制效应通过滚环扩增反应增强了 Fe-MIL-88 信号探针的局部浓度，从而大大提高了灵敏度。该技术简单、一次性、高灵敏度和选择性，可在 1 fg/mL 至 250 ng/mL 的范围内检测 OTA，检测限为 0.22 fg/mL（3σ 规则）。此外，我们成功地检测了玉米、小麦和红酒样品中的 OTA，与商业酶联免疫试剂盒获得的结果具有良好的一致性。
