Antibacterial properties of silver containing diamond like carbon coatings produced by ion induced polymer densification

Diamond-like carbon (DLC) is known to be a versatile coating material for biomedical applications like endoprosthesis and dental implants. It provides mechanical robustness and cell-compatibility at the same time. To even more broaden this range of beneficial properties, it is tried to add antibacterial properties by incorporating silver nanoparticles. In this paper we discuss a novel approach to producing such coatings, capable of circumventing typical drawbacks of conventional deposition methods. To investigate the potential antibacterial properties an in vitro adhesion assay was created. Thereto Streptococcus sanguinis (DSM 20068) responsible for initial biofilm formation in peri-implant infection has been used. The results clearly show that silver nanoparticles are crucial for the antimicrobial effect as long as they are incorporated in the DLC-surface so that the adhering bacteria are directly exposed.