We present experimental evidence of a transition in the short-time Brownian motion of colloids from diffusive to subdiffusive, Rouse-like. This transition is seen for particles that are bound, through physical adsorption, to transient polymer networks. The characteristic Rouse scaling of the mean square particle displacement with $\sqrt{t}$, found in the experiments, is rationalized using an analytical bead-spring model of a large particle anchored to a set of polymer chains.

• Received 13 August 2007

DOI:https://doi.org/10.1103/PhysRevLett.99.208301