Tribology in biology

Man has conducted research in the field of tribology for several thousands of years. Nature has been producing lubricants and adhesives for millions of years. Biotribologists gather information about biological surfaces in relative motion, their friction, adhesion, lubrication and wear, and apply this knowledge to technological innovation as well as to the development of environmentally sound products. Ongoing miniaturisation of technological devices such as hard disk drives and biosensors increases the necessity for the fundamental understanding of tribological phenomena at the micro- and nanometre scale. Biological systems excel also at this scale and might serve as templates for developing the next generation of tools based on nano- and microscale technologies. Examples of systems with optimised biotribological properties are: articular cartilage, a bioactive surface which has a friction coefficient of only 0.001; adaptive adhesion of white blood cells rolling along the layer of cells that lines blood vessels in response to inflammatory signals; and diatoms, micrometre sized glass making organisms that have rigid parts in relative motion. These and other systems have great potential to serve as model systems also for innovations in micro- and nanotechnology.