Credit: Alexander Aius
Key points:
- Surface oxygen in graphene materials plays an integral role in how effectively they kill bacteria.
- Researchers say the impact of surface oxygen content on the interaction mode has long been underestimated.
- This discovery may lead to the design of safer and more effective products to fight antimicrobial resistance.
The amount of surface oxygen in graphene materials plays an integral role in how effective they are in killing bacteria. This discovery may lead to the design of safer and more effective products to fight antimicrobial resistance.
Graphene oxide with high surface oxygen content (SOC) is very flexible and can easily wrap around bacteria, But, when it has lower SOC, the material becomes more rigid and tends to contact bacteria edgewise.
In findings published in ACS nano, an international group of scientists from the UK, Cyprus, Austria, Finland, The Netherlands and China reveal that it is graphene oxide’s different interaction modes that lead to distinct antibacterial activity—with a “switch” occurring when surface oxygen levels reach a certain threshold.
The UK- led international research team created a series of graphene materials with different SOCs and compared their antibacterial performance, evaluating total cell growth, biofilm formation and oxidative stress, as well as physical interactions with bacteria including through molecular simulations.
The team's findings show the connection between interaction modes and their distinct antibacterial activity. Interaction mode relies highly on the rigidity of graphene materials, which depends on the amount of oxygen on the surface.
“The impact of SOC on the interaction mode has been underestimated for a long time,” said Zhiling Guo from the University of Birmingham.
“Our research highlights that surface oxygen levels can help to evaluate the antibacterial effects of graphene materials, helping to design safer materials through clarifying the role of SOC,” said Peng Zhang, also from the University of Birmingham.