Ultrasensitive detection of nucleic acids using deformed graphene channel field effect biosensors
Ultrasensitive detection of nucleic acids using deformed graphene channel field effect biosensors
复制标题
使用变形石墨烯通道场效应生物传感器对核酸进行超灵敏检测
DOI：
10.1038/s41467-020-15330-9
复制
发表时间：
2020-03-24
影响因子：
16.6
通讯作者：
Bashir, Rashid
中科院分区：
文献类型：
--
作者：
Hwang, Michael Taeyoung;Heiranian, Mohammad;Bashir, Rashid
基于场效应晶体管（FET）的生物传感器通过测量生物分子的固有电荷实现无标记检测。这些传感器的检测极限由溶液中反离子对电荷的德拜屏蔽所决定。在此，我们使用具有变形单层石墨烯沟道的场效应晶体管来检测核酸。这些即使具有毫米级沟道的器件在缓冲液和人血清样本中分别展现出低至600仄摩尔（zM）和20阿摩尔（aM）的超高灵敏度检测，这大约相当于18个和大约600个核酸分子。计算模拟表明，纳米级变形可在传感沟道中形成“电学热点”，从而减少凹区的电荷屏蔽。此外，变形的石墨烯可能呈现出带隙，使得源漏电流因少量电荷而呈指数变化。总之，这些现象使得在毫米级结构中实现超灵敏的电子生物分子检测成为可能。
Field-effect transistor (FET)-based biosensors allow label-free detection of biomolecules by measuring their intrinsic charges. The detection limit of these sensors is determined by the Debye screening of the charges from counter ions in solutions. Here, we use FETs with a deformed monolayer graphene channel for the detection of nucleic acids. These devices with even millimeter scale channels show an ultra-high sensitivity detection in buffer and human serum sample down to 600 zM and 20 aM, respectively, which are similar to 18 and similar to 600 nucleic acid molecules. Computational simulations reveal that the nanoscale deformations can form 'electrical hot spots' in the sensing channel which reduce the charge screening at the concave regions. Moreover, the deformed graphene could exhibit a band-gap, allowing an exponential change in the source-drain current from small numbers of charges. Collectively, these phenomena allow for ultrasensitive electronic biomolecular detection in millimeter scale structures.