In materials science, roughness on a micrometer and nanometer scale plays an important role in contact-related phenomena, such as tribology or adhesion. It is also well known that roughness over a wide range of length scales affects the biological response to surfaces, e.g. cell adhesion, morphology, proliferation and differentiation. The understanding of these cellular behaviors in connection to the surface topography is crucial in the further development of medical implants.
However, the influence of roughness in biological and materials science applications has only rarely been systematically studied. Yet the findings of such systematical studies would greatly facilitate the tailoring of a surface for a specific application rather than creating surfaces by purely empirical approaches.
Motivated by the demand of substrata to systematically study roughness-related phenomena, methods for the generation of morphological gradients on different roughness scales have been developed at LSST. First a gradient of micrometer roughness-size feature was developed, by slow immersion of a sand-blasted aluminum sheet into a polishing solution. A nanometer roughness feature-size gradient was achieved by immersion of a flat silicon wafer into a silica particle suspension. Both those gradients have been combined to create an orthogonal gradient, in order to study the synergetic effects of both micrometer and nanometer feature-size roughness in any combination.
- Morphological gradients for biomedical applications
Christian Zink, PhD Thesis, No. 19925, ETH Zürich, 2011.
- Surface Morphology Gradients
Tobias Künzler, PhD Thesis, No. 17049, ETH Zürich, 2007.
- Self-assembly of functionalized nanoparticles into microarrays and gradients
Christoph Huwiler, PhD Thesis, No. 16783, ETH Zürich, 2006.
- Orthogonal nanometer-micrometer roughness gradients probe morphological influences on cell behavior
Zink, C.; Hall, H.; Brunette, D. M.; Spencer, N. D., Biomaterials, 2012, 33(32) pp 8055-8061.
- Effects of Surface Micro-Topography on the Assembly of the Osteoclast Resorption Apparatus
Geblinger, D.; Zink, C.; Spencer, N. D.; Addadi, L.; Geiger, B., Journal of the Royal Society Interface, 2012, 9(72) pp 1599-1608.
- Systematic Study of Osteoblast Response to Nanotopography by means of Nanoparticle-Density Gradients
Künzler, T.; Huwiler, C.; Drobek, T.; Vörös, J.; Spencer, N. D., Biomaterials, 2007, 28(33) pp 5000-5006.
- Functionalizable Nano-Morphology Gradients via Colloidal Self-Assembly
Huwiler, C.; Künzler, T.; Textor, M.; Vörös, J.; Spencer, N. D., Langmuir, 2007, 23(11) pp 5929-5935.
- Systematic Study of Osteoblast and Fibroblast Response to Roughness by means of Surface- Morphology Gradients
Künzler, T.; Drobek, T.; Schuler, M.; Spencer, N. D., Biomaterials, 2007, 28(13) pp 2175-2182.