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Nanostrukturen und Grenzflächen Poster: Do., 13:00–15:30 D-P310
Ion track-etched nanopores in polymer foils
Birgitta Schiedt 1 , Javier Cervera 2 , Ken Healy 3 , Salvador Mafe 4 , Alan P.
Morrison 3 , Reinhard Neumann 1 , Gerard Pepy 5 , Patricio Ramirez 6 , Zuzanna
Siwy 7 , Christina Trautmann 1
1 Gesellschaft für Schwerionenforschung (GSI), Planckstr. 1, 64291 Darmstadt, Germany
– 2 Dept. de Ciències Experimentals., Universitat Jaume I. Apdo. 224, E-12080
Castello, Spain – 3 Dept. of Electrical and Electronic Engineering, University College
Cork, Ireland – 4 Dept. de Termodinàmica, Universitat de València, E-46100 Burjassot,
Spain – 5 BNC, SzFKI, POB 45 Budapest, Hungary – 6 Dept. de Fisica Aplicada. Univ.
Politècnica de València, Camino de Vera s/n, E-46022 Valencia, Spain – 7 Department
of Physics and Astronomy, University of California, Irvine, 2182 Frederick Reines Hall,
Irvine, CA 92697
Track-etching has become an established method to create well-defined pores in polymer
membranes with diameters down to a few nanometers. The irradiation of insulating
materials with swift heavy ions of MeV to GeV energy creates damaged zones along
the trajectories of the ions which can be attacked preferentially by a suitable etchant
and are thus converted into pores. The number of pores in a membrane is given by
the applied fluence, i.e. number of ions per surface area (typically between one single
ion and 10 9 ions/cm 2 ), while their size and shape is controlled via the time and conditions
of etching. Cylindrical pores with diameters down to a few tens of nanometers
or alternatively conical pores with a few nanometers opening on the small side can be
produced.
Structural analysis of cylindrical track-etched nanopores in polycarbonate has been
performed by small angle x-ray scattering and revealed an excellent uniformity in pore
size, if the samples have been exposed to UV light prior to the etching.
Single pore membranes with a conical shape show ionic transport properties similar
to biological channels (selectivity, rectification, fluctuations [1][2]). To better understand
the underlying processes occurring in the system, model calculations based on
the Nernst-Planck and Poisson equations have been performed, describing the transport
phenomena (I-V curves at different concentrations) of conical pores in polyethyleneterephthalate
[3].
These synthetic nanopores have the advantage of high stability, resistance against
environmental conditions and easy-handling, which makes them a favourable system
for applications in biosensing [4] and single-molecule (e.g. DNA) detection [5].
[1] P.Y. Apel et al., Nucl. Inst. Meth. B 184 (2001) 337. [2] Z. Siwy et al., Am. J.
Phys. 72 (2004) 567. [3] J. Cervera et al., J. Chem. Phys. 124 (2006) 104706. [4] E.A.
Heins et al., Nano Lett. 5 (2005) 1824. [5] A. Mara et al., Nano Lett. 4 (2004) 497.