Despite the recent research on bacterial production techniques it has long been known that graphene possesses anti-bacterial qualities. As far back as July 2010 a study conducted by Chunhai Fan, a professor in the Laboratory of Physical Biology at the Shanghai Institute of Applied Physics, showed that as well as being anti-bacterial graphene derivatives had the added benefit of being bio-compatible with human cells.
Now, twenty two months later, a team of scientists headed by Bingan Lu of Lanzhou University have shown that graphene combines with chitosan, a blood clotting agent, to produce a wound dressing that significantly reduces the time it takes for a wound to completely heal.
Lu’s team created a graphene-chitosan membrane from nanofibres and then applied them to a range of small skin wounds in a way similar to a band-aid dressing. Inspection ten days later showed that the grphene-chitosan wounds showed significantly better rates of repair than those not treated with the membrane.
Chunhai Fan, one of the originators of the work on graphene’s antibacterial properties commented that the finding,
‘shows a really interesting health application of graphene-based nanomaterials… [and] clearly shows that graphene-based antibacterial materials facilitate wound healing’.
Graphene’s bio-compatibility with human cells makes this finding a breakthrough for nanomedicine, as previous trials with silver nanoparticles, also known to be antibacterial, have suggested an accompanying level of cytotoxicity. The damage caused to bacterial cells by electron transfer across the cell wall does not seem to occur in animal cells, possibly because they possess a secondary cell wall. One hypothesis to explain the anti-bacterial power of graphene is that the electron transfer results in the destruction of the bacteria’s DNA. Chunhai Fan’s earlier research supports this view, his own work on E. coli bacteria suggesting that cellular integrity is disrupted, leading to the cell membrane being severely destroyed and the cytoplasm flowing out.
The original research can be read in Nanoscale, 2012, DOI: 10.1039/c2nr11958g