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Probing Single Nanometer-Scale Pores with Polymeric Molecular Rulers



Sarah E. Henrickson, Edmund A. DiMarzio, Qian Wang, Vincent M. Stanford, John J. Kasianowicz


It has been shown that individual molecules of single stranded DNA can be driven electrophoretically through a single Staphylococcus aureus ?-hemolysin ion channel. Polynucleotides thread through the channel as extended chains and the polymer-induced ionic current blockades exhibit stable modes during the interactions. Additionally, we show here that polynucleotides can be used to probe structural features of the ?-hemolysin channel itself. Specifically, both pore length and channel aperture profile can be estimated. The results are consistent with the channel crystal structure and suggest that polymer-based ?molecular rulers? may prove useful in deducing the structures of nanometer- scale pores in general.
Journal of Chemical Physics


alpha hemolysin, alpha toxin, DNA, ion channel, nanopore, polymer confinement, polynucleotide, structure-function


Henrickson, S. , DiMarzio, E. , Wang, Q. , Stanford, V. and Kasianowicz, J. (2010), Probing Single Nanometer-Scale Pores with Polymeric Molecular Rulers, Journal of Chemical Physics, [online], (Accessed June 13, 2024)


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Created April 1, 2010, Updated October 12, 2021