SPrAM, UMR5819, CEA/CNRS/UJF, INAC, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France.
Anal Chem. 2012 Apr 3;84(7):3254-61. doi: 10.1021/ac2033744. Epub 2012 Mar 13.
The use of biological-probe-modified solid-state pores in biosensing is currently hindered by difficulties in pore-wall functionalization. The surface to be functionalized is small and difficult to target and is usually chemically similar to the bulk membrane. Herein, we demonstrate the contactless electrofunctionalization (CLEF) approach and its mechanism. This technique enables the one-step local functionalization of the single pore wall fabricated in a silica-covered silicon membrane. CLEF is induced by polarization of the pore membrane in an electric field and requires a sandwich-like composition and a conducting or semiconducting core for the pore membrane. The defects in the silica layer of the micropore wall enable the creation of an electric pathway through the silica layer, which allows electrochemical reactions to take place locally on the pore wall. The pore diameter is not a limiting factor for local wall modification using CLEF. Nanopores with a diameter of 200 nm fabricated in a silicon membrane and covered with native silica layer have been successfully functionalized with this method, and localized pore-wall modification was obtained. Furthermore, through proof-of-concept experiments using ODN-modified nanopores, we show that functionalized nanopores are suitable for translocation-based biosensing.
生物探针修饰的固态孔在生物传感中的应用目前受到孔壁功能化困难的阻碍。待功能化的表面较小且难以定位，并且通常在化学上与大块膜相似。在此，我们展示了非接触式电功能化（CLEF）方法及其机制。该技术能够对在覆盖有二氧化硅的硅膜中制造的单个孔壁进行一步局部功能化。CLEF 通过在电场中对孔膜进行极化而产生，并且需要孔膜的夹层状组成和导电或半导体核。微孔壁的二氧化硅层中的缺陷使通过二氧化硅层创建电通路成为可能，这允许在孔壁上局部发生电化学反应。使用 CLEF 进行局部壁修饰时，孔径不是限制因素。已经使用这种方法成功地对在硅膜中制造并覆盖有天然二氧化硅层的直径为 200nm 的纳米孔进行了功能化，并获得了局部孔壁修饰。此外，通过使用 ODN 修饰的纳米孔进行的概念验证实验，我们表明功能化的纳米孔适用于基于转位的生物传感。
