Green-Based Modifications of Polyethylene Surfaces Enhancing Antifouling Properties in Water-Related Systems

The effects of fouling in plastics, such as polyethylene (PE), can have a major economic impact due to tube clogging and other issues. Surface properties, both chemical and physical, can substantially influence biofilm formation, so developing antifouling materials through engineering these properties is very promising. In this work, two main approaches are evaluated for reducing the fouling on PE surfaces: chemical modification with green coating (polyethylene glycol (PEG) and different chitosan nanoparticles (CS NPs)) and physical modification with distinct micro-topographies. First, the antibacterial adhesion is tested with Escherichia coli. The results reveal that CS NPs result in a considerable decrease in adhesion depending on which source of chitosan is used. PEG coating only reduced adhesion by 26%, while CS NPs with a high molecular weight (CS3) decreased adhesion by 88% in relation to non-modified surfaces. Moreover, lozenges topographic modification (T2) has the highest effect on the bacteria adhesion within the physically-modified PE surfaces. Finally, CS3 and T2 surfaces are tested in water samples in dynamic conditions for 27 days and results showed lower bacterial adhesion than unmodified surfaces. Overall, both strategies offer eco-friendly and cost-effective solutions for preventing fouling and extending the lifetime of polymeric surfaces for environmental applications.