Multi-scale strain-stiffening of semiflexible bundle networks.

Autor: Piechocka IK; FOM Institute AMOLF, 1098 XG Amsterdam, The Netherlands. gkoenderink@amolf.nl., Jansen KA, Broedersz CP, Kurniawan NA, MacKintosh FC, Koenderink GH
Jazyk: angličtina
Zdroj: Soft matter [Soft Matter] 2016 Feb 21; Vol. 12 (7), pp. 2145-56. Date of Electronic Publication: 2016 Jan 13.
DOI: 10.1039/c5sm01992c
Abstrakt: Bundles of polymer filaments are responsible for the rich and unique mechanical behaviors of many biomaterials, including cells and extracellular matrices. In fibrin biopolymers, whose nonlinear elastic properties are crucial for normal blood clotting, protofibrils self-assemble and bundle to form networks of semiflexible fibers. Here we show that the extraordinary strain-stiffening response of fibrin networks is a direct reflection of the hierarchical architecture of the fibrin fibers. We measure the rheology of networks of unbundled protofibrils and find excellent agreement with an affine model of extensible wormlike polymers. By direct comparison with these data, we show that physiological fibrin networks composed of thick fibers can be modeled as networks of tight protofibril bundles. We demonstrate that the tightness of coupling between protofibrils in the fibers can be tuned by the degree of enzymatic intermolecular crosslinking by the coagulation factor XIII. Furthermore, at high stress, the protofibrils contribute independently to the network elasticity, which may reflect a decoupling of the tight bundle structure. The hierarchical architecture of fibrin fibers can thus account for the nonlinearity and enormous elastic resilience characteristic of blood clots.
Databáze: MEDLINE