01/31/2017
Graphene blocks antibiotic resistant bacteria
Technology often imitates nature. And to reduce the risk of infection during surgery, doctors may soon turn to surgical implements coated with graphene oxide, inspired by the typical rough texture of crab shells, which protects them from bacteria.
"The European Centre for Disease Prevention and Control has announced that since 2009, over 400,000 Europeans have developed bacterial infections that are resistant to antibiotics. We thus face the need to devise new strategies to defend surgical tools and prostheses from this type of bacteria," explains Claudio Conti, ISC-CNR Director and Professor at the Sapienza Department of Physics, who co-authored the study. "We began by observing the solutions proposed by nature and decided to imitate them, copying crab shells whose surface texture repels bacteria."
Researchers further honed the efficiency of this approach by employing graphene, a material that is already famed for its antimicrobic properties. "We developed a hydrogel graphene oxide-based coating," explains Massimiliano Papi, co-author and Physics Professor at the Università Cattolica del Sacro Cuore. "The nanometric layers of graphene oxide are able to pierce and cut bacterial cell membranes and prevent bacterial infection where antibiotics fail."
This anti-bacterial mechanism can be amplified through a laser printing technique discovered by the research team: laser super-cavitation. "The laser action allows the graphene sheets to be moulded exactly like a crab shell. Analyses on the morphology and release of nucleic acids by cells of Staphylococcus aureus, Escherichia coli and Candida albicans reveal that the coating is both bacteriostatic and anti-bacterial, defeating 90% of known bacteria. This is an enormous result, a true turning point in the field of biomedical products. It is versatile, cheap and has extremely limited toxicity," adds Professor Conti.
The research project was conducted by a joint team including members from the Sapienza Physics Department, the National Research Council (ISC-CNR), the Institute of Physics and Microbiology at the Rome Università Cattolica del Sacro Cuore and the University of L'Aquila.
Source: Universita di Roma