The emergence of collective motion exhibited by systems ranging from flocks of animals to
self-propelled microorganisms to the cytoskeleton is a ubiquitous and fascinating self-…

A magnetic bead microrheometer has been designed which allows the generation of forces
up to 10 4 pN on 4.5μm paramagnetic beads. It is applied to measure local viscoelastic …

In living cells the mechanical properties of the actin cytoskeleton are defined by the local
activation of different actin cross-linking proteins. These proteins consist of actin-binding …

The actin cytoskeleton, a network of protein-polymers, is responsible for the mechanical
stability of cells. This biopolymer network is also crucial for processes that require spatial and …

We measured the viscoelastic properties of the cytoplasm of J774 macrophages with a
recently developed microrheometer. Ferromagnetic beads (1.3μm in diameter) were used to …

We study the thermal motion of colloidal tracer particles in entangled actin filament (F-actin)
networks, where the particle radius is comparable to the mesh size of the F-actin network. In …

Engineering synthetic materials that mimic the remarkable complexity of living organisms is
a fundamental challenge in science and technology. We studied the spatiotemporal patterns …

We measure the viscoelasticity of entangled F-actin over length scales between 1 and 100
μ m using one-and two-particle microrheology, and directly identify two distinct microscopic …

The transport of microscopic particles such as growth factors, proteins, or drugs through the
extracellular matrix (ECM) is based on diffusion, a ubiquitous mechanism in nature. The …

Bundles of filamentous actin (F-actin) form primary structural components of a broad range
of cytoskeletal processes including filopodia, sensory hair cell bristles and microvilli. Actin-…