Zhu Fengxi, Zhao Qiang
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Anal Methods. 2025 Feb 13;17(7):1487-1492. doi: 10.1039/d4ay02231a.
The serious contamination of ochratoxin A (OTA) in agricultural products has promoted the development of rapid, sensitive, and selective analytical methods for OTA monitoring. We demonstrated a competitive aptasensor for OTA detection using CRISPR/Cas12a as an effective signal amplifier. OTA competes with complementary DNA of the aptamer on the microplate to bind to the aptamer. Streptavidin bridges the biotinylated aptamer and biotinylated activator to convert the OTA input into Cas12a activation, which cleaves fluorescent DNA reporters. Under optimized experimental conditions, the aptasensor was demonstrated to work well for sensitive detection of OTA, with a linear range from 0.5 nM to 62.5 nM and a detection limit of 0.5 nM. Moreover, our method not only exhibits high selectivity, but also has satisfactory anti-interference ability against complex sample matrices. Taken together, the CRISPR/Cas12a-based competitive aptasensor offers a simple and sensitive platform for OTA detection, and it holds great promise for food security monitoring.
农产品中赭曲霉毒素A（OTA）的严重污染推动了用于OTA监测的快速、灵敏和选择性分析方法的发展。我们展示了一种使用CRISPR/Cas12a作为有效信号放大器的竞争性适体传感器用于OTA检测。OTA与微孔板上适体的互补DNA竞争结合适体。链霉亲和素桥接生物素化的适体和生物素化的激活剂，将OTA输入转化为Cas12a激活，从而切割荧光DNA报告分子。在优化的实验条件下，该适体传感器被证明可很好地用于OTA的灵敏检测，线性范围为0.5 nM至62.5 nM，检测限为0.5 nM。此外，我们的方法不仅具有高选择性，而且对复杂样品基质具有令人满意的抗干扰能力。综上所述，基于CRISPR/Cas12a的竞争性适体传感器为OTA检测提供了一个简单且灵敏的平台，在食品安全监测方面具有巨大潜力。
