Development and Evaluation of Modified Dlc Coatings to Minimize Pseudomonas Fluorescens Adhesion

Si and N-doped DLC coatings with various Si and N contents were prepared using a magnetron sputter ionplating technology. The antifouling property of DLC coatings was evaluated with Pseudomonas fluorescens which is one of the most common bacteria forming biofilms on the surface of heat exchangers in cooling water systems. The experimental results showed that bacterial removal by a standardised washing procedure increased significantly with increasing electron donor values and with decreasing electron acceptor values of DLC coatings. The incorporation of 2%N into the Si-doped DLC coatings further significantly reduced bacterial attachment and significantly increased bacterial removal. The best Si-Ndoped DLC coatings reduced bacterial attachment by 58% and increased removal by 41%, compared with a standard silicone coating, SilasticT2. Bacterial adhesion strength on the DLC coatings is explained in terms of thermodynamic work of adhesion. − S γ