**Tribology for Biological and Medical Applications**

Noritsugu Umehara, Takayuki Tokoroyama and Hiroyuki Kousaka

**1. Introduction**

Tribology is the science and technology of two interacting surfaces in relative motion and of related subjects and practices. The field of tribology is interdisciplinary. Until recently, it has been dominated by mechanical and chemical engineers who conducted macro‐tests to predict friction and wear in machine components and developed new lubricants. After the develop‐ ment of biological engineering and medical engineering, tribology for various interacting surfaces of human, creatures, cells and so on has keen attention in bio‐technology. Also interaction of surfaces between medical devices and bio‐cells as a blood is becoming to be interested. On the basis on the old tribology, we can not solve issues for bio‐medical applica‐ tions, because bio and medical surfaces are basically soft and changed their mechanical and chemical properties with temperature drastically. So we should propose and develop novel technology for bio‐medical applications.

In this chapter, we introduce several new technologies to reduce adhesion of thermally coagulated blood [1, 2] and fish proteins [3] to metal surface for a radio knife and grill rods respectively. Also ion beam irradiation increased the bonding strength of a probe DNA to polymer substrate for a DNP sequence tip in low price [4]. And in orderto reduce the adhesion and friction of rubber, plasma and UV irradiation methods were proposed for the rubber plunger of disposal plastic syringe [5] and rubber plug of medicine bottle [6] respectively. Those proposed surface technologies for biological and medical applications will be explained in the following sections.
