Au nanoparticles/hollow molybdenum disulfide microcubes based biosensor for microRNA-21 detection coupled with duplex-specific nuclease and enzyme signal amplification

作者：Shuai, Hong-Lei; Huang, Ke-Jing^*; Chen, Ying-Xu; Fang, Lin-Xia; Jia, Meng-Pei

来源：Biosensors and Bioelectronics, 2017, 89: 989-997.

DOI：10.1016/j.bios.2016.10.051

• Hollow molybdenum disulfide microcubes
• Duplex-specific nuclease
• MicroRNAs
• Enzyme signal amplification
• Electrochemical biosensor

An ultrasensitive electrochemical biosensor for detecting microRNAs is fabricated based on hollow molybdenum disulfide (MoS2) microcubes. Duplex-specific nuclease, enzyme and electrochemical chemical chemical redox cycling are used for signal amplification. Hollow MoS2 microcubes constructed by ultrathin nanosheets are synthesized by a facile template-assisted strategy and used as supporting substrate. For biosensor assembling, biotinylated s5DNA capture probes are first immobilized on Au nanoparticles (AuNPs)/MoS2 modified electrode in order to combine with streptavidin-conjugated alkaline phosphatase (SA-ALP). When capture probes hybridize with miRNAs, duplex-specific nuclease cleaves the formative duplexes. At the moment, the biotin group strips from the electrode surface and SA-ALP is incapacitated to attach onto electrode. Then, ascorbic acids induce the electrochemical chemical chemical redox cycling to produce electrochemical response in the presence of ferrocene methanol and tris (2-carboxyethyl) phosphine. Under optimum conditions, the proposed biosensor shows a good linear relationship between the current variation and logarithm of the microRNAs concentration ranging from 0.1 fM to 0.1 pM with a detection limit of 0.086 fM (S/ N=3). Furthermore, the biosensor is successfully applied to detect target miRNA-21 in human serum samples.

• 出版日期2017-3-15
• 单位信阳师范学院