Nano-mechanical Characterization of Thin Film of Type I Collagen Fibrils by Atomic Force Microscopy

원자력 현미경을 이용한 Type I Collagen Fibrils 박막의 기계적 특성 연구

The mechanical cues that adherent cells derive from the extracellular matrix (ECM) can effect dramatic changes in cell migration, proliferation, and differentiation. Using a thin film of Type I collagen fibrils comprised of 100 nm to 200 nm collagen fibrils overlaying a bed of smaller fibrils, changes in cellular response to systematically controlled changes in mechanical properties of collagen was investigated. Further, an experimental and modeling approaches to calculate the elastic modulus of individual collagen fibrils, and thereby the effective stiffness of the entire collagen thin film matrix, from atomic force microscopy force spectroscopy data was performed. These results demonstrate an approach to analysis of fundamental properties of thin, heterogeneous, organic films, and add further insights into the mechanical properties of collagen fibrils that are of relevance to cell response to the ECM.