The latest piece of research to emerge from the University of Houston and Case Western Reserve University has shown that graphene may be used as a antimicrobial coating for surgical equipment and other surfaces. The news reinforces findings announced earlier this year by Prof Bingan Lu and strengthens the case for the use of graphene composites in applications where bacterial infection is thought problematic.
Reporting in the journal Nanotechnology the research has shown that the the graphene based composite developed during the study shows both anti-bacterial properties and low mammalian toxicity. The toxicity of graphene is obviously a crucial factor to be considered before the nano-material could be incorporated into any medical device.
The particulars of the research, headed up by Debora Rodrigues and Rigoberto Advincula, involved the preparation of highly stable graphene (G) poly(N-vinylcarbazole) (PVK) dispersions and films. The PVK-G (97/3 w/w %) nanocomposite solutions and thin films were then tested against Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis), the film showing an approximately 80% inhibition of bacterial growth.
The high bio-compatibility of the exfoliated PVK-G film was evidenced by an equivalent 80% cell survival rate.
The findings from Houston and Case Western Reserve also compliment the findings of Chunhai Fan whose recent work on graphene paper shows how graphene enters the endosome of the bacteria’s cytoplasm, pushing it out of the cell. In Fan’s experiment almost 99% of the cells were destroyed after just two hours in contact with a 85 g/mL solution of graphene oxide at 37 °C. In contrast, the nanosheets were not toxic to mammalian cells under the same conditions. Prof. Fan suggested,
Ultimately we wish to develop new antibacterial materials from graphene that could be directly applied onto skin to aid in wound healing. However, we are aware that it is still a challenge to mass produce graphene nanomaterials, and particularly to fabricate large-scale graphene paper.
As ever, the findings of both research teams strongly support the claim that investing in graphene is truly an investment in the future.