KEYWORDS

Articular Cartilage Surface, Phospholipids Bilayers, Lamellar-Repulsive Lubrication, Friction and Wettability, Interfacial Energy

THE LAMELLAR-REPULSIVE MECHANISM OF LUBRICATION OF NATURAL JOINTS

The amphoteric effect on the friction between the bovine cartilage/cartilage contacts has been found to be highly sensitive to the pH of an aqueous solution. The cartilage surface was characterized using a combination of the pH, wettability, as well as the interfacial energy and friction coefficient test methods to support lamellarrepulsive mechanism of lubrication. It has been confirmed experimentally, that phospholipid (PLs) multi-bilayers are essentially described as lamellar frictionless lubricants which protect the surface of the joints against wear. The low friction would then be due to (a) lamellar slippage of bilayers and (b) a short-range repulsion between the interfaces of negatively charged (-PO4-) cartilage surfaces.

AUTHORS

Z. Pawlak, Tribochemistry Consulting, Salt Lake City, UT, A. Gadomskic, University of Technology and Life Sciences, Bydgoszcz, Poland, M. Hagner-Derengowska, University of Bydgoszcz, Bydgoszcz, Poland, W. Urbaniak, Kazimierz Wielki University, Bydgoszcz, Poland, P. Beldowski, University of Technology and Life Sciences, Bydgoszcz, Poland