Interfacial Engineering of Zwitterionic Copolymer Brushes toward Biofouling-Resistant PDMS Surfaces

Biofouling caused by the adhesion of microorganisms and suspended particles remains a major challenge in marine environments, leading to the deterioration of device performance and increased maintenance costs. In particular, underwater sensors and soft electronic systems are highly susceptible to surface contamination, highlighting the need for durable antifouling interfaces. In this study, a zwitterionic copolymer brush was engineered on a PDMS substrate to develop a biofouling-resistant interface inspired by the surface characteristics of Laminaria japonica. The copolymer brush, composed of the zwitterionic monomer 2-(methacryloyloxy)ethyl dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA) and the hydrophobic monomer 2,2,2-trifluoroethyl methacrylate (TFEMA), was designed to balance surface hydration and hydrophobicity. Antifouling evaluation against diatoms and silt particles demonstrated that the engineered surface effectively reduced both biological and particulate fouling. Building on these findings, bioinspired microtopographical structures will be incorporated into the copolymer brush system to construct hierarchical antifouling surfaces that integrate chemical and structural antifouling mechanisms. This interfacial engineering strategy is expected to contribute to the development of durable biofouling-resistant surfaces for underwater sensing systems, marine robotics, and biomedical devices.