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.