Soikkeli Miika, Kurppa Katri, Kainlauri Markku, Arpiainen Sanna, Paananen Arja, Gunnarsson David, Joensuu Jussi J, Laaksonen Päivi, Prunnila Mika, Linder Markus B, Ahopelto Jouni
VTT Technical Research Centre of Finland Ltd. , P.O. Box 1000, FI-02044 VTT, Espoo, Finland.
School of Chemical Technology, Aalto University , P.O. Box 6100, FI-00076 AALTO, Espoo, Finland.
ACS Appl Mater Interfaces. 2016 Mar;8(12):8257-64. doi: 10.1021/acsami.6b00123. Epub 2016 Mar 21.
We demonstrate a label-free biosensor concept based on specific receptor modules, which provide immobilization and selectivity to the desired analyte molecules, and on charge sensing with a graphene field effect transistor. The receptor modules are fusion proteins in which small hydrophobin proteins act as the anchor to immobilize the receptor moiety. The functionalization of the graphene sensor is a single-step process based on directed self-assembly of the receptor modules on a hydrophobic surface. The modules are produced separately in fungi or plants and purified before use. The modules form a dense and well-oriented monolayer on the graphene transistor channel and the receptor module monolayer can be removed, and a new module monolayer with a different selectivity can be assembled in situ. The receptor module monolayers survive drying, showing that the functionalized devices can be stored and have a reasonable shelf life. The sensor is tested with small charged peptides and large immunoglobulin molecules. The measured sensitivities are in the femtomolar range, and the response is relatively fast, of the order of one second.
我们展示了一种基于特定受体模块的无标记生物传感器概念，该受体模块为所需分析物分子提供固定化和选择性，同时结合石墨烯场效应晶体管进行电荷传感。受体模块是融合蛋白，其中小疏水蛋白作为锚定物来固定受体部分。石墨烯传感器的功能化是一个基于受体模块在疏水表面定向自组装的单步过程。这些模块在真菌或植物中分别产生，并在使用前进行纯化。这些模块在石墨烯晶体管通道上形成致密且取向良好的单层，并且可以去除受体模块单层，原位组装具有不同选择性的新模块单层。受体模块单层在干燥后仍能存活，这表明功能化器件可以储存并且具有合理的保质期。该传感器用小的带电肽和大的免疫球蛋白分子进行了测试。测得的灵敏度在飞摩尔范围内，响应相对较快，约为一秒量级。
