The Realm of the Nanopore

Abstract

The realm of The nanopore Interest in nanoscale research has skyrocketed, and the humble pore has become a king.Jennifer Griffiths little more than 10 years ago, a group of scientists made a discovery that would revolutionize the way DNA was sequenced-or so they hoped. In their 1996 paper (1), the team, which included John Kasianowicz of the U.S. National Institute of Standards and Technology, Daniel Branton of Harvard University, and David Deamer of the University of California Santa Cruz, showed that they could use an electric field to drive single-stranded DNA and RNA molecules into the aperture of a proteinaceous transmembrane ion channel and use the pore as a sensor. "It was very clearly allowing us to detect individual [DNA] molecules and [to] begin to learn something about the character of these molecules," says Branton. "The very first thing we noticed was that we could obviously determine the length or the size of the molecule C. Dekker, TU DelfT/Tremani J A n u A r y 1 , 2 0 0 8 / A n A l y t i c A l c h e m i S t r y 2 3

Nernst-Planck model of photo-triggered, pH–tunable ionic transport through nanopores functionalized with “caged” lysine chains

“…These values are in good agreement with those found in previous studies of MVCl 2 and Na 2 NDS diffusion through nanoporous membranes. 45,63 In the case of acidic or basic pH, the membrane is charged and the Nernst-Planck equations must be solved using numerical procedures.…”

“…7a) gave a surface charge density  = -0.3e nm -2 at pH = 9.5, where e is the elementary charge, and pK C = 4.5. Because at pH = 9.5 all the carboxylate groups are in charged form, it can be concluded that the surface density of groups attached to the pore walls is approximately n C = 0.3 groups/nm 2 . The values of n C and pK C are in agreement with those found in previous studies for the case of pores functionalized with carboxylate groups.…”

“…Nanoscale pores have been studied extensively in the last decade due to the new basic phenomena involved and the potential applications in medicine, [1][2][3] nanofluidics, [4][5][6][7] membrane science 8,9 and biotechnology. 10,11 Polymer samples containing single asymmetric nanopores and multipore arrays obtained by track-etching 12 are of particular interest because they mimic some of the transport properties of biological ion channels.…”

Disentangling Steric and Electrostatic Factors in Nanoscale Transport Through Confined Space

“…In nanopore analytics, single molecules are detected via the passage-induced changes in ionic current. [2][3][4][5][6][7] The approach can be implemented with protein 4,[8][9][10] and solid-state nanopores [10][11][12][13][14][15][16] and has gained popularity 17 due to its simplicity, the wide range of accessible analytes, 2,13,[18][19][20] and the prospect of DNA sequencing [21][22][23] based on nucleic acid sensing. [24][25][26][27] The translocation of protein and DNA strands through protein channels is also a biologically relevant process in pathogenic bacteria and human cells.…”

Applications of polymer single nanochannels in biosensors

“…Biological ion channels located at the cell walls and composed of protein complexes could open and close in response to external stimuli for dominating ion translocation and play crucial role in the creature metabolism process [1]. Inspired by ion channels, researchers have developed various kinds of artificial nanopores or nanochannels to construct biosensors or other devices [2][3][4][5][6][7][8][9][10][11][12][13]. Strictly speaking, under the premise of insuring at least one dimension in the range of one to several dozens of nanometers, pore diameter larger than its depth is simply defined as nanopore while oppositely defined as nanochannel.…”