Ceria-Incorporated Biopolymer for Preventing Fungal Adhesion

Although biopolymers are widely used in biomedical fields, the issue of poor antimicrobial properties remains unsolved, leading to a potential increase in infections. Here, ceria nanoparticles (CNPs) were incorporated into a representative biopolymer, poly(methyl methacrylate) (PMMA), for drug-free antimicrobial properties. After characterizing the CNPs and surface/mechanical properties of the CNP-PMMA nanocomposite, antiadhesive effects against Candida albicans, the most common fungal species responsible for fungal infections, were determined using metabolic activity assays, and the underlying microbial antiadhesive mechanism was revealed. Hydrothermally fabricated CNPs showed a size of ∼20 nm with a zeta potential of 12 ± 2.3 mV and showed catalytic properties as a ROS modulator. Successful incorporation of CNPs into PMMA up to 2 wt % was confirmed by EDS analysis. The surface roughness and mechanical properties such as flexural strength and modulus were relatively unchanged up to 2 wt %. In contrast, the surface energy increased, and the Vickers hardness decreased in the 2 wt % PMMA compared with the control. A drop of up to 90% of adherent Candida albicans was observed in CNP-incorporated PMMA, which was confirmed and quantified via fungus staining images. The antiadhesive mechanism was revealed from the direct antimicrobial effects of CNP via the upregulation of the intracellular ROS level. Taken together, the antimicrobial-adhesive properties of the CNP-PMMA nanocomposite suggest the potential usefulness of CNP as a promising drug-free antimicrobial ingredient for biopolymers, which could lead to the prevention of microbial-induced complications in clinical settings.