Cartilage has exceptional tribological properties, in particular at low sliding velocities – far from any synthetic material. In this project, we will investigate the mechanical behavior of native ovine cartilage over many length, time and force scales to understand how nature achieved these properties. Cartilage of different age will be sheared, compressed, dehydrated or chemically stressed and then investigated on various scales by macrorheology (MR), indentation measurements, and atomic force microscopy (AFM). We will directly quantify the friction processes taking place between two cartilage surfaces with friction AFM and MR tribology measurements. A special emphasize will be put on the role of the lubricant, which is synovial liquid in natural joints. In addition, we will monitor the flow of liquid in and out of cartilage during compression/ relaxation with fluorescence microscopy. By additionally using gain or loss of function principles and the combined multiscale approaches we will get unique insights into the ability of cartilage to recover its initial material properties and in the crucial molecular components for this behavior. Our approach will therefore pinpoint important bioinspired strategies on how to construct suitable cartilage substitutes. The project will be tightly integrated in the Focus Area Biomaterials. The unique combination of macro-, micro- and nanoscopic methods combined with the wide range of force and time scales studied will allow for a new quality in the understanding of the biomechanical properties of cartilage and guide the path to bio-inspired optimized cartilage substitutes.
Boettcher, K., Kienle, S., Nachtsheim, J., Burgkart, R., Hugel, T., & Lieleg, O.: "The structure and mechanical properties of articular cartilage are highly resilient towards transient dehydration”, 2016.
Grumbein, S., Minev, D., Tallawi, M., Boettcher, K., Prade, F., Pfeiffer, F., & Lieleg, O.: "Hydrophobic Properties of Biofilm Enriched Hybrid Mortar", 2016.
Arends, F., Nowald, C., Pflieger, K., Boettcher, K., Zahler, S., Lieleg, O.: "The biophysical properties of basal lamina gels depend on the biochemical composition of the gel",2015.
Kienle, S., Boettcher, K., Wiegleb, L., Urban, J., Burgkart, R., Lieleg, O., & Hugel, T.: "Comparison of friction and wear of articular cartilage on different length scales", 2015.
Crouzier, T., Boettcher, K., Geonnotti, A. R., Kavanaugh, N. L., Hirsch, J. B., Ribbeck, K., Lieleg, O.: "Modulating Mucin Hydration and Lubrication by Deglycosylation and Polyethylene Glycol Binding”,2015.
Grumbein, S., et al.: "Selected metal ions protect Bacillus subtilis biofilms from erosion", 2014.
Boettcher, K., Grumbein, S., Winkler, U., Nachtsheim, J., Lieleg, O.: "Adapting a commercial shear rheometer for applications in cartilage research", 2014.
Dr.-Ing. Kathrin Both
Dr. rer. nat. Bettina Kracke
Molecular and Cellular Biophysics
Dr.-Ing. Stefan Grumbein