Superparamagnetic colloidal flats: A route to studying the non-linear mechanics of actin networks

A cell's capacity to detect and respond to physical stimuli is largely attributed to actin networks in their cytoskeleton. Consequently, a number of techniques have been developed to study the mechanics of actin networks, including the magnetic chaining of superparamagnetic colloidal beads. Whilst the latter has huge statistical power, it is not well suited to probe, exactly, non-linear responses. In this talk, I will outline a novel method to fabricate superparamagnetic colloidal flats which do allow charachterisation of the non-linear elasticity of actin networks. Further, because the fabrication route controls both the initial pre-field position and the 2D geometry of the flats, I will demonstrate how these factors influence the flats' chaining characteristics under homogeneous magnetic fields.