基于染料Genefinder和适配体的荧光传感体系检测赭曲霉毒素A

构建基于核酸染料Genefinder和适配体的荧光传感体系用于检测赭曲霉毒素A（ochratoxin A，OTA）。OTA适配体与其互补链形成双链结构，Genefinder染料与双链结构DNA结合后产生较强的荧光信号，加入OTA后，适配体与OTA结合形成四链体结构，双链打开，Genefinder染料荧光强度降低。结果表明，该荧光传感体系的线性范围为50 pg/L～300 ng/L，实际检出限为50 pg/L，对OTA有较强的选择性。这种简单、快速、特异性强的荧光传感体系具有广泛的应用前景。

A Fluorescent Sensing System Based on Genefinder and Aptamer for the Detection of Ochratoxin A

A fluorescence sensing system based on the nucleic acid dye Genefinder and aptamer was constructed for the detection of ochratoxin A (OTA) in this study. A double-stranded structure was formed by binding the OTA aptamer to its complementary strand. Binding of Genefinder to double-stranded DNA (dsDNA) generated a strong fluorescent signal. In the presence of OTA, the aptamer bound to it to form a quadruplex structure, melting the double strands and leading to a decrease of the fluorescence intensity of Genefinder. The results showed that the linear range of the sensing system was 50 pg/L–300 ng/L, and the detection limit was 50 pg/L. The sensing system had a high selectivity for OTA and could be widely applied as a simple and fast method.