Reduced graphene oxide-chitosan flexible nanocomposites for efficient bacteria capture and photothermal ablation

One of the major public health concerns today is bacterial infection-associated diseases. Traditional antibacterial therapies are becoming less efficient because frequent and inadequate use of antibiotics has caused mutations in bacteria that led to many antibiotic-resistant bacterial strains. It is, therefore, crucial to develop novel antibacterial materials and strategies that will successfully combat both gram-positive and gram-negative bacteria. In the present study, we will demonstrate a simple and efficient method for bacteria capture and elimination through photothermal ablation. The developed material consists of a flexible Kapton substrate, coated with reduced graphene oxide-chitosan (rGO-CS) thin films. Reduced graphene oxide has strong absorption in the near-infrared (NIR) region, while chitosan has the ability to bind bacteria through electrostatic interactions. The K/rGO-CS device proved to capture and efficiently eradicate both planktonic Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacteria after 10 min of NIR (980 nm) irradiation.