Berlin 2005 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 14: Polymer physics at the surface
CPP 14.2: Vortrag
Montag, 7. März 2005, 16:45–17:00, TU C130
MANIPULATION OF SINGLE POLYMER MOLECULES ON SOLID SUBSTRATES — •Nikolai Severin1, Wei Zhuang1, Jörg Barner1, Alexei Kalachev2, Evgeniy An3, Viktor Ivanov3, and Jürgen P. Rabe1 — 1Department of Physics, Humboldt University Berlin, Newtonstr. 15, D-12489, Berlin, Germany — 2PlasmaChem GmbH, Rudower Chaussee 29, 12489, Berlin, Germany — 3Chair of Physics of Polymers and Crystals, Physics Department , Moscow State University, Moscow 119992 , Russia
We report on the manipulation of single macromolecules on solid surfaces. The macromolecule-surface interaction was tuned with alkylated amphiphile molecules, which self-assemble on crystalline substrates like the basal plane of graphite into monolayers with head groups and alkyl tails phase separated into lamellae. These lamellae can serve as soft nanoscopic ’rails’ along which the polymer orients. ds-DNA molecules with contour lengths of up to 2 micrometers have been moved as a whole in a single manipulation step on a layer of dodecylamine (1). The length distribution of the polymer molecules adsorbed on the ’nano-structured’ surface is considerably different from the length distribution in solution, which we attribute to the entropy loss of the molecules stretched on the ’nano-rails’. We visualize the coil-globule transition of poly(sodium 4-styrenesulfonate) by trapping the over-all conformation in solution on the surface.
(1) Severin, N.; Barner, J.; Kalachev, A.A.; Rabe, J.P. Nano Letters 2004, 4, 577-579.