Antibacterial activity and long-term stable antibacterial performance of nisin grafted magnetic GO nanohybrids

In this study, magnetic graphene oxide (MGO) nanohybrids were firstly fabricated by loading Fe₃O₄ NPs onto GO nanosheets and then novel nisin grafted MGO (nisin-g-MGO) nanohybrids were prepared by a facile method. The nisin-g-MGO nanohybrids exhibit strong enough magnetic separation capacity. The magnetic saturation (Ms) of nisin-g-MGO nanohybrids was 23.3 emu/g that enables nisin-g-MGO nanohybrids can be rapidly and completely separated from the black and stable suspension by an external magnet. The antibacterial studies of nisin-g-MGO nanohybrids show great antibacterial performance against Staphylococcus aureus and Bacillus subtilis, respectively. Moreover, the nisin-g-MGO nanohybrids exhibit long-term antibacterial stability that they still keep their good antibacterial activity after six months storage. Meanwhile, the fabricated nisin-g-MGO nanohybrids exhibit good biocompatibility without any obvious effect on HEK293 cell viability due to the calculated cell viabilities were more than 95%. And no observed changes in cell morphology were found in nisin-g-MGO nanohybrids treated HEK293 cells. Hence, the fabricated nisin-g-MGO nanohybrids exhibit great potentials in antibacterial application.