Controlled Alignment of Graphene Oxide for Unraveling Edge-Mediated Cytotoxicity Mechanisms and Fabricating Anti-Biofouling Surfaces

Graphene-based nanomaterials (GBNs) have attracted substantial research interest over the past decade because of their extraordinary physicochemical properties. In engineered applications of GBNs, especially biomedical and environmental, the cytotoxicity of GBNs is of critical concern, given the inevitable exposure of living organisms to GBNs. Therefore, a deeper understanding of the interaction of GBNs with biological membranes is important for the risk assessment of environmental exposure as well as the design of graphene-enabled antimicrobial materials. In the first part of my talk, I will describe our recent effort on unraveling edge-mediated toxicity mechanism of the GBNs. Utilizing the alignability of graphene oxide (GO) in a magnetic field, we developed a new platform to fabricate composite films with aligned GO nanosheets exposed on the surface, which enabled the control of GO orientation when interacting with bacterial cells for elucidating edge-mediated toxicity effect. In the second part, I expanded the antibacterial mechanisms and alignment techniques of GO and applied them for the fabrication of a novel desalination membrane with vertically-aligned GO. The membrane possesses enhanced antimicrobial activity compared to the non-aligned samples, demonstrating its potential in delaying the onset of biofouling in desalination processes.