Nanoscopic research makes big impact

With the increasing emergence of drug-resistant strains of bacteria, it is becoming progressively more important to find alternative ways to thwart disease.

Research is beginning to focus on how cells stick to surfaces, and which surfaces might repel bacteria. Scientists hope this will provide a new edge to prevent infections before they start.<br />
This is exactly the goal of a team of researchers at the University of Waterloo and the University of California, Berkeley. They recently discovered how individual cells of the bacteria <em>Staphylococcus aureus</em> interact with structures on a nickel surface.

Most often, <em>S. aureus</em> is responsible for food poisoning or skin infections, however in more serious cases it can cause toxic shock syndrome, infections in knees joints, kidneys, lungs, and heart valves, and death. These bacteria are of particular concern in implant surgeries for prosthetic joints and heart valves, as well as in the food service and food supply industries.

&ldquo;It is possible to develop a surface that the bacterial cells do not like to adhere [to],&rdquo; said Dr. Ting Tsui, professor of chemical engineering and lead of the group of UW researchers working on the project<em>.</em> &ldquo;This can be used in areas of medical devices, implants, and food packaging.&rdquo;

This research is the first of its kind to investigate this topic at the individual cell level &mdash; a scale of only a few hundred nanometres.

Researchers hoped to discover what types of 3-D structures the bacteria prefer to stick to. They created a field of evenly spaced rows of pillars, each about twice as wide as a typical <em>S. aureus</em> cell, and formed in one of five shapes. After allowing enough time for attachment, researchers washed the area with deionized water, leaving only the most strongly bound cells.

Using an electron microscope, results show that bacteria do have a preference for certain structures; individual cells were most often found attached to O- or C-shaped pillars.

Alongside preventing infection and fighting antibiotic-resistant strains of disease, understanding how bacteria interact with various surface features may also help to reduce dependence on chemicals for anti-bacterial cleaning. Tsui said that the next step will be to continue experimenting with different types of nanostructures and cells.

The findings from this project can be found in the May 2014 (Volume 35, Issue 15) edition of the journal <em>Biomaterials.</em>