Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Electrically tunable solid-state silicon nanopore ion filter | Nanoscale Res Lett 2007 2 61-68 DOI s11671-006-9031-7 NANO EXPRESS Electrically tunable solid-state silicon nanopore ion filter Julien Vidal Maria E. Gracheva Jean-Pierre Leburton Received 27 September 2006 Accepted 8 November 2006 Published online 19 December 2006 to the authors 2006 Abstract We show that a nanopore in a silicon membrane connected to a voltage source can be used as an electrically tunable ion filter. By applying a voltage between the heavily doped semiconductor and the electrolyte it is possible to invert the ion population inside the nanopore and vary the conductance for both cations and anions in order to achieve selective conduction of ions even in the presence of significant surface charges in the membrane. Our model based on the solution of the Poisson equation and linear transport theory indicates that in narrow nanopores substantial gain can be achieved by controlling electrically the width of the charge double layer. Keywords Ion channels Artificial nanopore Silicon materials Nanofluidics Introduction Ion channels have been extensively studied during the past years for their essential role in cell biology. Their most important properties are the regulation of ion flow and their ion selectivity 1 2 as they allow only certain type of ions to cross through cell membranes J. Vidal . Leburton El Department of Electrical and Computer Engineering University of Illinois at Urbana-Champaign Urbana IL 61801 USA e-mail jleburto@ J. Vidal M. E. Gracheva . Leburton Beckman Institute for Advanced Science and Technology University of Illinois at Urbana-Champaign Urbana IL 61801 uSa depending on the cell ion concentration and the membrane surface charge. In this process the cell controls the flow of ions by a biological gate at the bottom of the channel thereby opening and closing a molecular sensor. This sensor reacts to change in concentration of certain types of ions and other biological signals. However biological sensors due .
