Corrosion behavior of Co28Cr6Mo implant in the presence of bovine serum albumin and hyaluronic acid

CoCrMo is one of the most widely used materials for prostheses. CoCrMo has high wear resistance, excellent corrosion resistance, and good biocompatibility. High corrosion resistance is ascribed to the formation of an oxide layer. However, the oxide layer does not remain intact in the corrosive body environment that contains oxygen, chloride, proteins, and carbohydrates. The presence of organic and inorganic species changes the oxide layer of CoCrMo to facilitate corrosion. Corrosion is one of the main issues that leads to revision surgery. CoCrMo has been used extensively in synovial joints replacements such as hip, knee, and shoulder. They are in contact with synovial fluid (SF) which mainly contains albumin and hyaluronic acid (HA). The concentrations of HA changes with age, sex, and diseases. The objective of this study is to investigate the effect of the main constituents of SF which are bovine serum albumin (BSA) and HA, on the corrosion performance of CoCrMo. In addition, this study also investigates the effect of changing HA concentrations on the corrosion behavior of CoCrMo. Increasing HA concentrations has reduced the pain for people with osteoarthritis. It may also have an effect on reducing the corrosion rate. To study the corrosion behavior of CoCrMo, different electrochemical techniques has been used to understand the formation and breakdown of the oxide layer, and calculate the corrosion rate by measuring the corrosion resistances and corrosion current densities. The results of electrochemical impedance spectroscopy (EIS) show that 4 gL-¹ of hyaluronic acid (HA) with bovine serum albumin (BSA) exhibited the highest corrosion resistance and the lowest corrosion rate of CoCrMo compared to only phosphate buffer saline (PBS), BSA, and PBS with different HA concentration.Applied Science, Faculty ofMaterials Engineering, Department ofGraduat