Effectiveness and Mechanisms of Recoverable Magnetic Nanoparticles on Mitigating Golden Mussel Biofouling

Mussel biofouling has become a problem
in aquatic ecosystems, causing
significant ecological impact and huge economic loss globally. Although
several strategies have been proposed and tested, efficient and environment-friendly
antifouling methods are still scarce. Here, we investigated the effects
of recoverable magnetic ferroferric oxide nanoparticles (Fe3O4-NPs) with different sizes (10 and 100 nm), coatings
(polyethylene glycol and polylysine), and concentrations (0.01 and
0.1 mg/L) on byssus adhesion-mediated biofouling by the notorious
golden mussel Limnoperna fortunei.
The results showed that magnetic Fe3O4-NPs,
especially negatively charged polyethylene glycol-coated Fe3O4-NPs, size- and concentration-dependently reduced the
byssus production, performance (breaking force and failure location),
and adhesion rate. Further investigations on mechanisms showed that
the down-regulation of foot protein 2 (Lffp-2) and energy-related
metabolic pathways inhibited byssus production. The declined gene
expression level and metal-binding ability of Lffp-2 significantly
affected foot protein interactions, further reducing the plaque size
and byssus performance. In addition, the change in the water redox
state likely reduced byssus performance by preventing the interface
interactions between the substrate and foot proteins. Our results
confirm the effectiveness and underlying mechanisms of magnetic Fe3O4-NPs on mitigating L. fortunei biofouling, thus providing a reference for developing efficient
and environment-friendly antifouling strategies against fouling mussels.