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New Cyclam-Based Fe(III) Complexes Coatings Targeting Cobetia marina Biofilms
Fábio M Carvalho1,2, Luciana C Gomes1,2, Rita Teixeira-Santos1,2
1LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
Molecules (Basel, Switzerland)
|February 26, 2025
Summary
Novel polyurethane coatings with cyclam-based Fe(III) complexes significantly reduced marine biofouling. These advanced coatings offer long-lasting protection against bacterial colonization by inhibiting biofilm formation and altering biofilm structure.
Area of Science:
- Marine Biology
- Materials Science
- Corrosion Science
Background:
- Biofouling poses significant challenges in marine environments, impacting infrastructure and operational efficiency.
- Environmentally friendly coatings are crucial for mitigating biofouling with long-lasting protective effects.
- Polyurethane (PU)-based coatings are being explored for their potential in marine applications.
Purpose of the Study:
- To investigate the antifouling performance of novel PU-based coatings incorporating cyclam-based Fe(III) complexes.
- To evaluate the efficacy of these coatings against *Cobetia marina* biofilm formation under controlled marine conditions.
- To analyze the impact of the complexes on biofilm architecture and bacterial cell characteristics.
Main Methods:
- Biofilm assays were conducted over 42 days under simulated marine hydrodynamic conditions.
- Colony-forming units (CFU) and flow cytometric (FC) analyses were used to quantify bacterial cells.
- Optical Coherence Tomography (OCT) and Confocal Laser Scanning Microscopy (CLSM) were employed to analyze biofilm structure and coverage.
Main Results:
- PU coatings with 1 wt.% cyclam-based Fe(III) complexes reduced *C. marina* biofilms by up to 50% (R=H) and 38% (R=HOCH2CH2CH2).
- OCT analysis revealed significant reductions in biofilm thickness (58-61%), biovolume (50-60%), and porosity (95-97%) on coated surfaces.
- CLSM confirmed decreased biofilm surface coverage, while FC indicated increased bacterial metabolic activity and ROS production.
Conclusions:
- Cyclam-based Fe(III) complexes incorporated into PU coatings show significant potential for deterring marine biofouling.
- These bioactive additives effectively inhibit bacterial colonization and alter biofilm structure, offering long-term protection.
- The developed coatings represent a promising environmentally friendly solution for marine biofouling challenges.
Keywords:
antifouling coatingbiofilm architecturecyclam-based complexesmarine biofoulingpolyurethane marine paintMore Related Videos
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