21. Antibacterial Effect of Materials and Biofilm

In this chapter, antibacterial effect is explained. Some materials could show the effects. From the viewpoint of their mechanism, antibacterial groups can be divided into three classes. The first consists of metallic materials such as silver, copper, etc. From some concrete examples, the metallic ions dissociated from the metals themselves or their compounds work to show antibacterial effects. The second class is composed of photocatalytic compounds. In this case, produced radicals control the bacterial growth. The third class contains organic materials. Generally, organic materials cause impairment of cell membranes inside the peptidoglycan. The first consists of antibacterial metals could control biofilm formation, since they would inhibit bacterial growth on material surfaces. However, biofilm control is basically a broader and more complicated concept than the antibacterial effect for planktonic bacteria. Therefore, more versatile countermeasures could be proposed to control biofilm formation and growth.