Affinity-Modulated Molecular Beacons on MoS2 Nanosheets for MicroRNA Detection
Affinity-Modulated Molecular Beacons on MoS2 Nanosheets for MicroRNA Detection
复制标题
MoS2 纳米片上的亲和力调制分子信标用于 MicroRNA 检测
DOI：
10.1021/acsami.8b14035
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发表时间：
2018
影响因子：
9.5
通讯作者：
Li Li
中科院分区：
文献类型：
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作者：
Xiao Mingshu;Ch;rasekaran Arun Richard;Ji Wei;Li Fan;Man Tiantian;Zhu Changfeng;Shen Xizhong;Pei Hao;Li Qian;Li Li
近年来，DNA功能化的层状过渡金属二卤代化合物在构建生物传感器方面引起了极大的兴趣。在这项工作中，我们报道了将多胞嘧啶(PolyC)尾巴固定在二硫化钼(MoS_2)纳米片上的双嵌段分子信标作为检测microRNA的探针。聚C段吸附在MoS2上，分子信标段可用于与靶点杂交；双链特异性核酸酶通过靶点循环提供信号放大。通过改变聚C的长度，调节探针在MoS2上的密度，抑制酶裂解的寡核苷酸的吸附，从而获得更高的猝灭效率。聚C介导的分子信标在MoS2上具有非常低的背景信号、超高的灵敏度(检测下限∼3.4fm)、检测单个核苷酸错配的特异性和从血清样本中检测目标microRNA的选择性。该检测平台在临床诊断和生物医学研究中对miRNAs的定量分析具有很大的潜力。
DNA-functionalized layered two-dimensional transition-metal dichalcogenides have attracted tremendous interest for constructing biosensors in recent years. In this work, we report diblock molecular beacons with poly-cytosine (polyC) tails anchored on molybdenum disulfide (MoS2) nanosheets as probes for microRNA detection. The polyC block is adsorbed on MoS2and the molecular beacon block is available for hybridization to the target; duplex-specific nuclease provides signal amplification by target recycling. By changing the length of polyC, we regulate the density of probes on MoS2and inhibit the adsorption of enzyme-cleaved oligonucleotides, thereby leading to higher quenching efficiency. PolyC-mediated molecular beacons on MoS2have very low background signal, ultrahigh sensitivity (limit of detection ∼3.4 fM), specificity to detect a single nucleotide mismatch, and selectivity to detect target microRNA from serum samples. This detection platform holds great potential for quantitative analysis of miRNAs in clinical diagnosis and biomedical research.