Graphene-Based Coating to Mitigate Biofilm Development in Marine Environments

Area of Science:

• Marine Biology
• Materials Science
• Biotechnology

Background:

• Biofouling poses significant economic and ecological challenges in the marine sector.
• There is a growing demand for antifouling coatings that do not release biocides.
• Carbon-based nanomaterials, including graphene, are emerging as potential antifouling agents.

Purpose of the Study:

• To investigate the impact of pristine graphene nanoplatelets (GNP) on the development of *Cobetia marina* biofilms.
• To explore the antibacterial mechanisms of GNP against marine bacteria.
• To assess the antifouling potential of a GNP/polydimethylsiloxane (PDMS) surface.

Main Methods:

• A GNP/polydimethylsiloxane (PDMS) surface with 5 wt% GNP (G5/PDMS) was fabricated and characterized.
• Flow cytometry was used to analyze bacterial responses to GNP exposure.
• Biofilm formation on G5/PDMS and PDMS surfaces was evaluated over 42 days under controlled hydrodynamic conditions.

Main Results:

• GNP exposure induced membrane damage, increased metabolic activity, and reactive oxygen species (ROS) production in *C. marina*.
• The G5/PDMS surface demonstrated significant reductions in *C. marina* biofilm cell count (up to 43%) and thickness compared to PDMS.
• Biofilm architecture analysis revealed reduced empty spaces (34%) and biovolume (25%) on the graphene-based surface.

Conclusions:

• Pristine graphene nanoplatelets effectively inhibit *Cobetia marina* biofilm development.
• GNP-based surfaces exhibit promising potential as environmentally friendly marine antifouling coatings.
• The study elucidates the antibacterial mechanisms of GNP, including membrane damage and ROS generation.