Corrosion of Metallic Biomaterials in Cell Culture Environments

+, Cl , Ca 2+ , HxPO4 netc.), amino acids, proteins, and organic acids. The pH of body fluid is buffered at 7.15~7.35 but it decreases down to 5.2 during an inflammation reaction. 1 The concentration of oxygen depends on the part of body: in the intercellular fluid and arterial blood, it is 1/80~1/4 and 2/3 rds of that under ambient conditions, respectively. 2 The kind of cell in the surrounding tissue depends on the part of body and varies as time proceeds after implantation. Just after implantation of the material, macrophages assemble around the implanted material as the initial stage in a foreign body reaction. Because macrophages secrete active oxygen species, which chemically attack the surface oxide film of metallic materials, the influence of the presence of macrophages has been investigated. 3,4