Resistances against antimicrobials are a growing problem in health care. The development of new antibiotics and antibacterial agents is extremely important in order to keep up with ever-evolving bacterial pathogens.

Georgios N. Karanikolos, Demokritos National Research Center, Athens, Greece, and Petroleum Institute, Abu Dhabi, United Arab Emirates, and colleagues have produced a composite, consisting of a graphene support and silver/copper bimetallic nanoparticles (NPs), which inhibits bacterial growth. The team used chemical vapor deposition (CVD) to synthesize graphene and then introduced oxygen functionalities (epoxy, hydroxyl, and carboxyl groups) on the graphene surface using ultrasound-supported oxidation. To attach metal nanoparticles to the graphene support, the researchers anchored metal ions to the oxygen functionalities and reduced them in situ.

The final composite material completely inhibits the growth of Escherichia coli bacteria. In this regard, it outperforms both the freestanding NPs and graphene decorated with either pure Ag or Cu nanoparticles. According to the researchers, this can be attributed to a synergistic effect between the two metals and to an improved distribution of the particles caused by the graphene support.

• Ag and Cu Monometallic and Ag/Cu Bimetallic Nanoparticle–Graphene Composites with Enhanced Antibacterial Performance,
  Anna Perdikaki, Angeliki Galeou, George Pilatos, Ioannis Karatasios, Nick K. Kanellopoulos, Anastasia Prombona, Georgios N. Karanikolos,
  ACS Appl. Mater. Interfaces 2016, 8, 27498–27510.
  DOI: 10.1021/acsami.6b08403