Silver-doped laser-induced graphene for potent surface antibacterial activity and anti-biofilm action

Abstract

Previously, laser-induced graphene (LIG) coated surfaces were shown to resist biofilm growth, although the material was not strongly antibacterial. Here, we show LIG surfaces doped with silver nanoparticles (Ag⁰ or AgNPs) as highly antibacterial surfaces. Starting from AgNO₃ polyethersulfone (PES) polymer substrates, silver nanoparticles between 5–10 nm were generated in situ during the lasing process and stably embedded in the fibrous and porous structure of LIG in a single step. These silver doped LIG (Ag@LIG) surfaces were highly toxic to bacteria via a mechanism of both Ag⁺ ion release and possible surface toxicity of the AgNPs. The added antibacterial function of Ag-nanoparticles expands the functionality of LIG coated surfaces and might lead to highly effective point of use/entry devices in rural areas or in disaster situations with contaminated water sources.