New degradable silicone-hydrogel marine coating resists bio-fouling

The novel coating achieved over 98？% inhibition of microbial growth in laboratory tests.

A Chinese research team has developed a silicone-hydrogel-based marine coating that combats bio-fouling through a fourfold mode of action. The material combines antimicrobial activity, controlled degradation and long-term flexibility.

A team from the Ningbo Institute of Materials Technology and Engineering (Chinese Academy of Sciences) has introduced a new degradable silicone-hydrogel coating designed for marine environments. Developed using a straightforward sol-gel process combined with Schiff base chemistry, the formulation integrates various monomer types to deliver antifouling, antimicrobial, and flexible properties.

The innovative coating addresses the key challenge of microbial fouling in marine engineering, such as on ship hulls or underwater infrastructure. While conventional solutions often rely on toxic biocides or suffer from poor durability, the new material demonstrated a 98.8？% bactericidal rate and prevented 99.8？% of microbial attachment in lab-scale tests.

Multi-mode performance and extended service life

The coating acts through four synergistic mechanisms: it forms an amphiphilic surface to prevent initial adhesion, resists microbial colonisation, eliminates attached bacteria and gradually renews itself as it degrades. Despite its degradability, the material maintains mechanical flexibility, with a reported hardness of 0.135.

Applied at a thickness of 200 μm, the coating is expected to last around five and a half years. In addition to marine use, the research team also sees potential for medical applications, such as coatings for implants or catheters where resistance to bacterial contamination is essential.

Source: Ningbo Institute of Materials Technology and Engineering