Carbon Nanotube-Polyamidoamine Dendrimer Hybrid-Modified Electrodes for Highly Sensitive Electrochemical Detection of MicroRNA24
Carbon Nanotube-Polyamidoamine Dendrimer Hybrid-Modified Electrodes for Highly Sensitive Electrochemical Detection of MicroRNA24
复制标题
碳纳米管-聚酰胺胺树枝状聚合物混合修饰电极用于 MicroRNA24 的高灵敏电化学检测
DOI：
10.1021/acs.analchem.5b00093
复制
发表时间：
2015-05-05
影响因子：
7.4
通讯作者：
Yao, Shouzhuo
中科院分区：
文献类型：
--
作者：
Li, Fengye;Peng, Jing;Yao, Shouzhuo
报道了一种简单、灵敏的基于多壁碳纳米管（MWCNT）-聚酰胺胺（PAMAM）树枝状大分子和亚甲基蓝（MB）氧化还原指示剂的microRNA（miRNA）电化学生物传感器。该测定利用了用MWCNT-PAMAM修饰的玻璃碳（GC）电极，其上固定有寡核苷酸捕获探针。通过测量探针与靶miRNA杂交前后MB的还原信号变化来完成miRNA的电化学检测（miRNA 24用作模型情况）。与裸GC电极相比，MWCNT-PAMAM/GC电极显示出对MB还原的极大增强的信号。MWCNT与PAMAM的官能化保持MWCNT对MB还原的电化学性质，但使MB在MWCNT表面上的不期望的吸附最小化。实验变量对miRNA检测的影响进行了研究和优化。杂交60 min后，检测限为0.5 fM，峰电流密度-浓度线性关系可达100 nM。该方法已成功应用于HeLa细胞总RNA中miRNA 24的检测。
A simple and ultrasensitive microRNA (miRNA) electrochemical biosensor employing multiwalled carbon nanotube (MWCNT)-polyamidoamine (PAMAM) dendrimer and methylene blue (MB) redox indicator is reported in this work. The assay utilizes a glass carbon (GC) electrode modified with MWCNT-PAMAM, on which the oligonucleotide capture probes are immobilized. The electrochemical detection of miRNAs is completed by measuring the reduction signal change of MB before and after the probe hybridization with target miRNA (miRNA24 is used as a model case). The MWCNT-PAMAM/GC electrode shows greatly enhanced signal to MB reduction in contrast to bare GC electrode. The functionalization of MWCNT with PAMAM maintains the electrochemical property of MWCNT to MB reduction but minimizes the undesired adsorption of MB on the MWCNT surface. The effect of experimental variables on the miRNA detection is investigated and optimized. A detection limit of 0.5 fM and a linear peak current density-concentration relationship up to 100 nM are obtained following 60 min hybridization. The proposed assay is successfully used to detect miRNA24 in total RNA sample extracted from He La cells.