基于靶标诱导滚环扩增的无标记适配体生物传感器快速检测赭曲霉毒素A

该文构建一种基于靶标诱导滚环扩增（rolling circle amplification，RCA）的无标记适配体快速检测赭曲霉毒素A（ochratoxin A，OTA）生物传感器。该生物传感器探针由RCA 引物与OTA 适配体两部分组成，在OTA 存在的环境中，OTA 适配体特异性识别靶标，探针结构被打开，RCA 引物与环状DNA 模板（circular DNA template，CT）结合开启RCA 反应，加入核酸染料SYBR Gold 产生荧光信号。此生物传感器具有较高的特异性，检测限为6.6×10-2 nmol/L，线性检测范围为6.6×10-2～660 nmol/L，可用于具体的分析检测。此生物传感器无需复杂化学修饰且操作简单，在食品安全检测中具有良好的应用前景。

A Label⁃Free Aptamer Biosensor for Rapid Detection of Ochratoxin A Based on Target⁃Induced Rolling Circle Amplification

A label?free aptamer biosensor was developed for the rapid detection of ochratoxin A（OTA）based on target?induced rolling circle amplification（RCA）.The probe of the biosensor consisted of two parts：RCA primer and OTA aptamer.In the presence of OTA，the probe could be opened，in which the OTA aptamer spe?cifically recognized the target，and the RCA primer bound to the circular DNA template（CT）to initiate the RCA.The SYBR Gold nucleic acid dye was added to generate a fluorescence signal.This biosensor had high specificity and a limit of detection as low as 6.6×10-2 nmol/L，with a wide linear detection range of 6.6×10-2 to 660 nmol/L.Furthermore，this biosensor can be successfully applied in the detection of OTA.This biosensor does not require complex chemical labeling and is simple to operate，which has promising applications in food safety detection.