生物潤滑液對超高分子量聚乙烯磨耗行為之影響

The Effects of Biological Lubricants on the Wear Behavior of UHMWPE

蘇毓智(Yu-Chih Su)

指導教授 ： 方旭偉

國立臺北科技大學/工程學院/生物科技研究所/碩士(2005年)

https://doi.org/10.6841/NTUT.2005.00105

摘要

人工關節的超高分子量聚乙烯（UHMWPE）元件的磨耗顆粒（wear particle）的產生，會啟動人體的免疫反應，進而引發骨溶解（osteolysis）現象，最後造成人工關節鬆脫損壞。解決的方法除了針對人工關節材料的改善以及設計上改良外，我們也尋找利用表面加工或是改變潤滑效果的方法，進一歩控制磨耗顆粒引發之生物反應程度的可能性。
本研究利用微米製程（microfabrication）製作的微米加工表面（surface texture），與磨耗測試機上UHMWPE進行加速磨耗試驗，並觀察在水和生物潤滑液如胎牛血清（bovine serum）、白蛋白（albumin）及玻尿酸（hyaluronic acid）溶液下磨耗行為的差異，藉此探討在生物體中控制磨耗顆粒大小形狀的參數，以及生物體液之摩擦潤滑現象。從實驗的結果發現利用微米加工之表面與UHMWPE對磨，我們可以控制產生出磨耗顆粒之大小及形狀，且在生物潤滑液環境下的磨耗顆粒長度均較水中來得小，具有較大的長寬比（aspect ratio），此可能為摩擦力降低以及對磨表面形成保護層所造成的邊界潤滑效應所致。然而在白蛋白及玻尿酸溶液中所產生的磨耗量較水中大，除水中會產生高分子轉移薄膜干擾磨耗機制外，所造成材料疲乏的機制不同也是影響的主因。進一步分析摩擦過程引發之生物潤滑液之結構變化，發現白蛋白經過磨耗後造成白蛋白變性，與UHMWPE表面接觸角變小，表示白蛋白吸附在對磨表面的能力增加，磨耗量因此變小，故白蛋白可能不適合做為邊界潤滑液。因未來仍需對人體關節液中主要影響潤滑性質的關鍵潤滑液分子研究，以找出運用於人工關節上合適的邊界潤滑液。

關鍵字

超高分子量聚乙烯 ； 磨耗顆粒 ； 邊界潤滑 ； 生物潤滑液 ； 加工表面

並列摘要

The wear particle of UHMWPE generated in the peri-prosthetic tissue may induce osteolysis and eventually caused prosthesis failure. The critical issue remains on the effects of wear particle size and shape on immunological responses. We are looking for the methods to control the wear particles-induced bioactivies by surface texturing techniques and lubricating improvements.
In this study, we applied microfabricated surface texture to rub against the UHMWPE pins in order to generate UHMWPE wear particles with specific size and shape. In order to simulate the environment in-vivo, we discussed the effects of wear behavior under biological lubrication such as bovine serum, albumin and hyaluronic acid. The outcome shows that thinner and fibril-like wear particles were found in biological lubricants. We also observed that the length of the particle generated in biological lubricants is smaller（larger aspect ratio）than that generated in water. It may be attributed to the reduction of friction force between UHMWPE and the cutting-edge on the surface. The results showed that the wear rate are larger in the biological lubricant. Based on our protein analyses, it is shown that the structure of protein was denatured after the tribological process. We also observed that the denatured albumin protein has a smaller contact on UHMWPE surface. It implies a larger coverage of the lubricating film on the UHMWPE surface. We may further investigate the association among the compositions of biological lubricant, tribochemistry of the molecules and the wear of UHMWPE materials.

並列關鍵字

UHMWPE ； wear particle ； boundary lubrication ； biological lubricant ； surface texture

參考文獻

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