The Effects of Synovial Fluid Compositions on the Friction of Artificial Joint Materials under the different test Condition

• Main Authors: Cheng-Yen Tsai, 蔡政諺
• Other Authors: 方旭偉
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/5969c3

碩士 === 國立臺北科技大學 === 化學工程研究所 === 96 === Joint prosthesis is mainly composed of cobalt-chromium-molybdenum (Co-Cr-Mo) and ultra-high molecular weight polyethylene (UHMWPE). However, the wear particles of UHMWPE are generated in the peri-prosthetic tissue may induce the innate immune response and osteolysis which lead to loosing of the total joint replacement. The motion of joints involves several lubrication models under CoCrMo-on-UHMWPE articulating surface between different nominal contact pressure and synovial fluid molecules. Therefore, in order to understand the role of the lubricating mechanism of synovial fluid, we should further study the influence of the different normal load and synovial fluid molecules on the tribological behaviors of artificial joints. In this study, we applied tribological test lubricant to albumin, γ-globulin, lipid, hyaluronic acid and multi-components in the synovial fluid. The result of the friction coefficient was showed lower under the contact pressure of 5MPa than 0.25MPa for one-component lubrication. The friction coefficient is lowest in the hyaluronic acid under the two contact pressure individually. However, multi-component in the synovial fluid interacts with each other, also influence the lubricating mechanism. Thereby, we have to investigate double components and multi-components synovial fluid lubrication mechanism of artificial joint. It was demonstrated that the friction coefficient were the lowest when lipid mixed hyaluronic acid than mixed albumin andγ-globulin under contact pressure of 5MPa. On the other hand, mixing the albumin, γ-globulin, lipid and hyaluronic acid are composed of physical concentration, it shows that the friction coefficient were lower without protein, but without hyaluronic acid were not. It could reduce friction force when the hyaluronic acid existed. The friction coefficient increase for the artificial joints when the lubricant contains proteins. It shows that the denatured albumin friction coefficient is higher than the nature albumin, and increase the contact pressure leads to the friction coefficient decrease. Changes in the molecular weight of albumin were measured by SDS-PAGE after friction experiment with a tribometer. We consequence of the covalent bond of albumin is destroyed by frictional shearing actions and then effects of friction coefficient to artificial joints. Thereby, the final goal of the study is to understand the abundant albumin in the synovial fluid under the frictional test system of the artificial joints.