A glass nanopore ionic sensor for surface charge analysis.

Surface charge-based nanopore characterization techniques unfold unique properties and provide a powerful platform for a variety of sensing applications. In this paper, we have proposed a nanoconfined inner wall surface charge characterization method with glass nanopores. The glass nanopores were functionalized with DNA aptamers that were designed for mercury (Hg 2+ ) ion immobilization by forming thymine-Hg 2+ -thymine structures. The surface charge of the nanopores was modulated by surface chemistry and Hg 2+ ion concentrations and analysed by combining zeta potential measurements on glass slides and the ionic current rectification ratio of the nanopores. Also, 1 pM Hg 2+ ions could be detected by the nanopores.