Influence of printing configuration on the resulting topology and antibacterial effectiveness of PVDF-graphene composites

Inherently antibacterial materials could be an effective method to reduce the spread and impact of bacterial infections when incorporated into health care settings. The aim of this study was to examine whether additively manufactured PVDF-graphene nanoplatelet composites could confer antibacterial effects. The composites and reference filaments were produced with thermal compounding extrusion, which is a scalable method commonly used in industry, and were successfully printed using fused filament fabrication. The composites reduced bacterial attachment by 21% and 81% within the first hour of exposure for Escherichia coli and Staphylococcus aureus respectively, when graphene flakes were exposed on the surface of the samples. E. coli strains were also examined for biofilm formation on the developed materials, but no additional antibacterial effect was seen, most likely because of the limited exposure of the graphene nanoplatelets on the surface of the samples. It was found that the surface topology resulting from different printing configurations, as well as the exposure time to bacteria had a significant influence on the biological response to the samples.