(402a) Exploring Actin Network Mechanics Via Synthetic Bio-Hybrid Crosslinkers

Biology is comprised of finely tuned active matter systems that respond to a plethora of biochemical and mechanical cues. A prime example is the actin cytoskeleton that reconfigures its architecture depending on environmental stimuli. Additionally, isotropically crosslinked actin networks are inherently mechanoresponsive, manifesting strain-stiffening behavior and mechanical hysteresis upon deformation. Due to these unique mechanical features, actin mimetic materials have garnered interest in recent years leading to the generation of several strain-stiffening hydrogels with biomedical applications. However, to further the development of mechanically hysteretic biomaterials, the molecular design criteria underpinning actin-network mechanics need further probing. Most current studies of actin networks rely on biologically relevant proteinaceous crosslinkers, thus, leading to coarse tuning of crosslinker design parameters. In this study, we probe the mechanical hysteresis of actin networks using synthetically produced bio-hybrid crosslinkers comprised of nanoparticles decorated with actin binding peptides. Such a construct allows for the finer control over crosslinker variables and their impact on actin network mechanics. Using fluorescence microscopy and bulk rheology, we demonstrate that these bio-hybrid constructs are effective crosslinkers and can reproduce the mechanical hysteresis inherent to native crosslinked actin networks.