Take a look around you and you will see a vast array of surfaces made of different materials. However, look at the finish of the surface and you will see that all surfaces have different roughness.
This image shows a microscopic comparison of surface roughness between polished (left) and brushed (right) stainless steel surfaces. The scale bar is 500 microns.
Generally, the surfaces within surgical and food processing environments are made of brushed surgical stainless steel, mainly for aesthetical reasons, but how does the surface topography affect its ability to become contaminated and subsequently its ease to decontaminate? Even surfaces that, at first sight, seem smooth (like polished metal and glass) can contain microscopic cracks, producing a perfect environment to harbour microbes and protein contaminants and protect them from cleaning.
In this project we look at the roughness of surfaces, even down to the microscopic level, and see whether the surfaces we use today might be improved in the future so that simple cleaning procedures can remove microbes from surgical tools, surgical surfaces, catheters, endoscopes etc. If we can prevent microbes and infectious material entering the body, people will not get infections from them. Fundamentally this can offset the problems caused by applying drugs (antimicrobials) to treat the infection, because the development of resistance to such drugs (antimicrobial resistance – AMR) will otherwise cause catastrophes in healthcare and food production.
Shown on the right is protein attachment to surface imperfections on a pair of crocodile forceps. The area of the forceps analysed (A), a magnified image of the surface roughness (B) and fluorescent stained protein residing in the imperfections of the surface (C). The scale bar is 500 microns.
This collaboration between surface engineering and biology attempts to shed light on this area and test the attachment and removal of AMR MRSA and prion proteins (associated with Creutzfeldt Jacob Disease (CJD)) to surgical stainless steel of varying roughness and hydrophobicity.
We will also be analysing the surface properties to try and find a correlation between attachment, ease to clean and the surface roughness. This aims to help advise the production of real world environments, such as surgical and food processing on the optimal finish of surfaces used and how this could aid infection prevention. Furthermore, this will give us an insight into how the wear of surgical instruments and surfaces will affect contamination and subsequently decontamination and help advice the medical industry when a surgical instrument is not fit for use and could be an infection risk.
NAMRIP Researchers: Dr. Thomas Secker and Mr. Mengyang Zhu
This project is funded by the EPSRC Network for Antimicrobial Action, 'Bridging the Gap' programme, EP/M027260/1 (Round 2 of NAMRIP Pump Priming).