Noncovalent functionalization of graphene oxide and reduced graphene oxide with Schiff bases as antibacterial agents

Conjugation of two or more substances to enhance the antibacterial properties of the resulting hybrids can be a useful method to fight bacterial resistance. In this work, a series of ligands composed of two Quaternary ammonium compounds (QAC) and chromene parts synthesized and then assembled on surfaces of graphene oxide (GO) and reduced graphene oxide (rGO). The formation of hybrids is caused by pi-pi interactions between GO/rGO and chromene part of ligands in addition to electrostatic interactions. The primary ligands only had an impact on Gram-positive and didn't exhibit activity against Gram-negative bacteria while the new hybrids showed increased effect on Gram-positive bacteria, also have a significant effect against Gram-negative bacteria. (c) 2017 Published by Elsevier B.V.