Zhang Fuyuan, Liu Linyang, Ni Shengnan, Deng Jiankang, Liu Guo-Jun, Middleton Ryan, Inglis David W, Wang Shuo, Liu Guozhen
ARC Centre of Excellence in Nanoscale Biophotonics (CNBP), Macquarie University, North Ryde, NSW 2109, Australia.
Graduate School of Biomedical Engineering, Faculty of Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
Nanomaterials (Basel). 2019 Jan 16;9(1):104. doi: 10.3390/nano9010104.
In order to satisfy the need for sensitive detection of Aflatoxin M1 (AFM1), we constructed a simple and signal-on fluorescence aptasensor based on an autocatalytic Exonuclease III (Exo III)-assisted signal amplification strategy. In this sensor, the DNA hybridization on magnetic nanobeads could be triggered by the target AFM1, resulting in the release of a single-stranded DNA to induce an Exo III-assisted signal amplification, in which numerous G-quadruplex structures would be produced and then associated with the fluorescent dye to generate significantly amplified fluorescence signals resulting in the increased sensitivity. Under the optimized conditions, this aptasensor was able to detect AFM1 with a practical detection limit of 9.73 ng kg in milk samples. Furthermore, the prepared sensor was successfully used for detection of AFM1 in the commercially available milk samples with the recovery percentages ranging from 80.13% to 108.67%. Also, the sensor performance was evaluated by the commercial immunoassay kit with satisfactory results.
为了满足对黄曲霉毒素M1（AFM1）进行灵敏检测的需求，我们基于一种自动催化的核酸外切酶III（Exo III）辅助信号放大策略构建了一种简单的、信号开启型荧光适配体传感器。在该传感器中，磁性纳米珠上的DNA杂交可由目标AFM1触发，导致单链DNA释放，从而引发Exo III辅助的信号放大，在此过程中会产生大量G-四链体结构，然后与荧光染料结合，产生显著放大的荧光信号，进而提高了灵敏度。在优化条件下，这种适配体传感器能够检测牛奶样品中的AFM1，实际检测限为9.73 ng/kg。此外，所制备的传感器成功用于检测市售牛奶样品中的AFM1，回收率在80.13%至108.67%之间。同时，通过商业免疫分析试剂盒对传感器性能进行评估，结果令人满意。
