Ultrasensitive electrochemical genosensor for detection of CaMV35S gene with Fe3O4-Au@Ag nanoprobe
Ultrasensitive electrochemical genosensor for detection of CaMV35S gene with Fe3O4-Au@Ag nanoprobe
复制标题
使用 Fe3O4-Au@Ag 纳米探针检测 CaMV35S 基因的超灵敏电化学基因传感器
DOI：
10.1016/j.talanta.2019.120205
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发表时间：
2020
期刊：
影响因子：
6.1
通讯作者：
Sundaram Gunasekaran
中科院分区：
文献类型：
--
作者：
Yongkang Ye;Shen Mao;Shudong He;Xuan Xu;Xiaodong Cao;Zhaojun Wei;Sundaram Gunasekaran
我们报道了一种阿托摩尔敏感的电化学基因传感器，用于检测花椰菜花叶病毒 35S (CaMV35S) 基因。三明治型基因传感器采用金银核壳(Au@Ag)负载氧化铁(Fe3O4)纳米复合材料(Fe3O4-Au@Ag)作为信号DNA探针(sDNA)的标记。通过捕获探针与目标 CaMV35S (tDNA) 以及 tDNA 与标记的 sDNA 之间的特异性相互作用，在电沉积 AuNP 和羧化多壁碳纳米管改性玻碳电极的界面处完成电化学传感。利用 Fe3O4-Au@Ag 增强的电催化活性，放大过氧化氢 (H2O2) 的还原信号，提高了检测灵敏度。在最佳实验条件下，计算出超低检出限为1.26×10−17M（S/N=3），且传感器的空白值减去H2O2还原信号在较宽的范围（1×10−16M至1×10−10 M）内随CaMV35S浓度的对数线性增加。该基因传感器表现出优异的稳定性、选择性和重现性，并成功检测转基因番茄样品中的目标CaMV35S。
We report an attomolar sensitive electrochemical genosensor for the detection of cauliflower mosaic virus 35S (CaMV35S) gene. The sandwich-type genosensor uses gold-silver core-shell (Au@Ag)-loaded iron oxide (Fe3O4) nanocomposite (Fe3O4-Au@Ag) as label of signal DNA probe (sDNA). Electrochemical sensing is accomplished at interface of electrodeposited AuNPs and carboxylated multiwalled carbon nanotubes-modified glassy carbon.electrode through the specific interaction between the capture probe and target CaMV35S (tDNA), and tDNA and the labeled sDNA. The detection sensitivity was improved by the amplified reduction signal of hydrogen peroxide (H2O2), which takes advantage of the enhanced electrocatalytic activity of Fe3O4-Au@Ag. Under the optimal experimental conditions, an ultralow limit of detection was calculated to be 1.26×10−17M(S/N=3), and the blank value subtracted reduction signal of H2O2 of the sensor increased linearly with the logarithm of CaMV35S concentration over a wide range (1×10−16M to 1×10−10 M). This genosensor displayed excellent stability, selectivity and reproducibility, and was successful in detecting the target CaMV35S in genetically modified tomato samples.