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CPP: Chemische Physik und Polymerphysik
CPP 28: Biological Systems
CPP 28.2: Vortrag
Freitag, 31. März 2006, 10:45–11:00, ZEU Lich
Force-induced desorption and unzipping of semiflexible polymers — •Jan Kierfeld — Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam
The thermally assisted force-induced desorption of semiflexible polymers from an adhesive surface or the unzipping of two bound semiflexible polymers by a localized force are investigated. The phase diagram in the force-temperature plane is calculated both analytically and by Monte Carlo simulations. Force-induced desorption and unzipping of semiflexible polymers are first order phase transitions. A characteristic energy barrier for desorption is predicted, which scales with the square root of the polymer bending rigidity and governs the initial separation process before a plateau of constant separation force is reached. This leads to activated desorption and unzipping kinetics accessible in single molecule experiments.