Urinary tract infections from catheters are the most common healthcare-associated infection and have been identified by the World Health Organization as an urgent global health threat. This study demonstrates the ability of microscopic structures on surfaces to prevent the initial establishment and growth of the three most common types of bacteria associated with urinary tract infections from catheters – Escherichia coli (E.coli), Klebsiella pneumoniae and Pseudomonas aeruginosa.
The team, led by Dr Victor Cadarso from Monash University, engineered several surfaces with smooth features at the micro scale. When tested, the smooth surfaces demonstrated reduction in both attachment of bacteria and formation of bacterial colonies. One of the surfaces showed 55-68% reduction in bacterial attachment, and 53-66% less colony formation.
Sara Ghavamian used Microscopy Australia’s Monash University facilities, MCEM and the Ramaciotti Centre for Cryo-EM, to prepare and image the bacteria attached to the surfaces to assess their antimicrobial effects. Fellow NCRIS facility, the Australian National Fabrication Facility, provided tools, such as the UV mask aligner, which allowed the researchers to fabricate the surfaces.
“Using E.coli as an example, we found that bacterial cells that colonise surfaces do so mostly on the sharp corners. By removing these sharp features, the bacteria can no longer colonise the surface as effectively. This same effect has been demonstrated for the two other pathogens in this study,” said Sara Ghavamian, from the Monash Department of Mechanical and Aerospace Engineering.
“Infection control through physically altering the micro architecture of these surfaces, rather than the traditional use of chemical agents, is not only a more durable approach but also an effective strategy for combating antimicrobial resistance.”
The study was published in the international journal ACS Applied Materials & Interfaces.
June 1, 2021