Size-dependent rheology of type-I collagen networks

TL;DR

This study explores how the rheological response of type-I collagen networks varies with system size, revealing that gel thickness influences stiffness and failure, impacting tissue mechanics and scaffold design.

Contribution

It demonstrates the size-dependent rheological behavior of collagen gels, linking gel thickness to network stiffening and failure mechanisms.

Findings

Gel stiffness depends on gel thickness in the strain-stiffening regime.

Network failure is governed by the ratio of gel thickness to mesh size.

Size effects have implications for tissue mechanics and biomimetic scaffold engineering.

Abstract

We investigate the system size dependent rheological response of branched type I collagen gels. When subjected to a shear strain, the highly interconnected mesh dynamically reorients, resulting in overall stiffening of the network. When a continuous shear strain is applied to a collagen network, we observe that the local apparent modulus, in the strain-stiffening regime, is strongly dependent on the gel thickness. In addition, we demonstrate that the overall network failure is determined by the ratio of the gel thickness to the mesh size. These findings have broad implications for cell-matrix interactions, the interpretation of rheological tissue data, and the engineering of biomimetic scaffolds.