Role of the biomolecular interactions in the structure and tribological properties of synovial fluid

► Healthy synovial fluid samples exhibit multilamellar vesicular discontinuities of several hundred nm in diameter. ► Hyaluronic Acid and lubricin exhibit high affinity and friction coefficient for the lipid bilayers. ► The glycoproteic components contained inside lipid multilamellar vesicles exhibit low friction coefficient. ► Synovial fluid volume is composed by a network of vesicles containing the glycoproteic gel separated by lipid multilayers. ► Synovial fluid interface is composed by a lipid multilayer anchored to cartilage's rubbing surface through lubricin.