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Trajectory approach to two-state kinetics of single particles on sculpted energy landscapes.

ABSTRACT: We study the trajectories of a single colloidal particle as it hops between two energy wells which are sculpted using optical traps. Whereas the dynamical behaviors of such systems are often treated by master-equation methods that focus on particles as actors, we analyze them instead using a trajectory-based variational method called maximum caliber (MaxCal). We show that the MaxCal strategy accurately predicts the full dynamics that we observe in the experiments: From the observed averages, it predicts second and third moments and covariances, with no free parameters. The covariances are the dynamical equivalents of Maxwell-like equilibrium reciprocal relations and Onsager-like dynamical relations.

SUBMITTER: Wu D

PROVIDER: S-EPMC3273425 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Trajectory approach to two-state kinetics of single particles on sculpted energy landscapes.

Wu David D Ghosh Kingshuk K Inamdar Mandar M Lee Heun Jin HJ Fraser Scott S Dill Ken K Phillips Rob R

Physical review letters 20090731 5

We study the trajectories of a single colloidal particle as it hops between two energy wells which are sculpted using optical traps. Whereas the dynamical behaviors of such systems are often treated by master-equation methods that focus on particles as actors, we analyze them instead using a trajectory-based variational method called maximum caliber (MaxCal). We show that the MaxCal strategy accurately predicts the full dynamics that we observe in the experiments: From the observed averages, it ...[more]

PMID: 19792475

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