Electrochemical aptamer-based nanosensor fabricated on single Au nanowire electrodes for adenosine triphosphate assay
Electrochemical aptamer-based nanosensor fabricated on single Au nanowire electrodes for adenosine triphosphate assay
复制标题
在单金纳米线电极上制造的基于电化学适体的纳米传感器用于三磷酸腺苷测定
DOI：
10.1016/j.bios.2017.08.020
复制
发表时间：
2018
影响因子：
12.6
通讯作者：
Li Yongxin
中科院分区：
文献类型：
--
作者：
Wang Dongmei;Xiao Xiaoqing;Xu Shen;Liu Yong;Li Yongxin
采用激光辅助提拉/氢氟酸刻蚀工艺制备了单根Au纳米线电极，并利用透射电镜、电化学方法和有限元模拟等手段对电极进行了表征。利用亚甲基蓝（MB）标记的双链DNA修饰在电极表面形成Au-S键，将所制备的单一AuNWEs用于构建电化学适配子纳米传感器（E-AB nanosensors）。在三磷酸腺苷（ATP）存在下，由于核酸适体与靶分子之间的强特异性亲和力，MB标记的核酸适体与双链体DNA解离，导致MB电化学信号减弱。此外，BSA被用来进一步钝化电极表面的键合位点，以保持传感器的稳定性。所制备的E-AB纳米传感器已被用于ATP的测定，具有良好的灵敏度和选择性，即使在复杂的系统，如大鼠脑的脑脊液。考虑到稳定性好、表面积更大、整体尺寸更小等独特性能，这种E-AB纳米传感器应该成为生物系统广泛传感应用的理想平台。
In this work, single Au nanowire electrodes (AuNWEs) were fabricated by laser-assisted pulling/hydrofluoric acid (HF) etching process, which then were characterized by transmission electron microscopy (TEM), electrochemical method and finite-element simulation. The as-prepared single AuNWEs were used to construct electrochemical aptamer-based nanosensors (E-AB nanosensors) based on the formation of Au-S bond that duplex DNA tagged with methylene blue (MB) was modified on the surface of electrode. In the presence of adenosine triphosphate (ATP), the MB-labeled aptamer dissociated from the duplex DNA due to the strong specific affinity between aptamer and target, which lead to the reduction of MB electrochemical signals. Moreover, BSA was employed to further passivate electrode surface bonding sites for the stable of the sensor. The as-prepared E-AB nanosensor has been used for ATP assay with excellent sensitivity and selectivity, even in a complex system like cerebrospinal fluid of rat brain. Considering the unique properties of good stability, larger surface area and smaller overall dimensions, this E-AB nanosensor should be an ideal platform for widely sensing applications in living bio-system.