The influence of protein concentration on the biotribological properties of the stem-cement interface
Issue title: Frontiers in Biomedical Engineering and Biotechnology – Proceedings of the 2nd International Conference on Biomedical Engineering and Biotechnology, 11–13 October 2013, Wuhan, China
Affiliations: State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
Note: [] This project is supported by National Natural Science Foundation of China (Grant No. 51005130), Scientific Research Starting Foundation for Returned Overseas Chinese Scholars, Ministry of Education of China (Grant No. 20121028121).
Abstract: The stem-cement interface in total hip replacement experiences fretting wear following debonding under cyclical physiological loading. However, the influence of protein concentration on the biotribological properties of this interface has not been well taken into consideration. In the present study, a series of fretting frictional tests were performed using polished Ti6Al4V and bone cement, lubricated by bovine serum albumin solutions of different concentrations (5%, 30%, and 75%). Surface characterizations of Ti6Al4V pins were conducted by optical interferometer, scanning electron microscope, and Raman spectroscopy. The results show that the friction coefficient decreases with the increase of protein concentration, although the difference is not significant. In addition, bovine serum albumin is adsorbed onto Ti6Al4V surface, forming a protective film to prevent the metal substrate from wear. The elemental and spectroscopic analyses of the film confirm the presence of protein molecules adsorbed on Ti6Al4V surface, with a thickness of 2.5 μm. It is indicated from this study that fretting wear at the stem-cement interface can be postponed by promotion of protein adsorption on the metal surface.
Keywords: stem-cement interface, biotribology, surface characterization, protein adsorption, bovine serum albumin
