Role of liquid crystals in the lubrication of living joints

Abstract

This investigation was devoted to the study of a natural phenomenon-low friction in living joints-and development of synthetic lubricants. The experiments conducted allowed us to establish that the known property of synovia to ensure the high antifrictional ability of joint cartilages is provided by the realization of a liquid-crystalline state of the lubricant in the friction zone that was unknown before. An idea was advanced that molecules of liquid-crystalline cholesterol compounds found in synovia are arranged with their longer axis aligned with prevailing microgroove locomotions on cartilage surfaces to make a liquid-crystalline nematic phase, thus reducing energy dissipation during relative motion of contacting cartilages and leading to the medicative effect revealed by experimentation.