Washington, July 1 (Inditop.com) Researchers have devised a micro-scale tool to follow the behaviour of bio-films – those slimy colonies of bacteria causing most infectious diseases.
Most bacteria exist as bio-films. Bacteria are single-celled organisms, but they rarely live alone, said John Younger, professor at the University of Michigan (U-M) Health System and study co-author.
The new tool is a micro-fluidic device, also known as a “lab-on-a-chip”. The device measures bio-films’ resistance to pressure.
Bio-films experience various kinds of pressure in nature and in the body as they squeeze through capillaries and adhere to the surface of medical devices, for example.
“If you want to understand bio-films and their life cycle, you need to consider their genetics, but also their mechanical properties,” said Mike Solomon, study co-author.
Mechanical forces are at play when our bodies defend against these bacterial colonies as well, Younger says.
The U-M micro-fluidic device provides the right scale. The channel-etched chip, made from a flexible polymer, allows researchers to study minute samples of between 50 and 500 bacterial cells that form bio-films of 10-50 microns in size. A micron is one-millionth of a metre. A human hair is about 100 microns wide.
The researchers found that the bio-films they studied had greater elasticity than previous methods had measured. They also discovered a “strain hardening response”, which means that the more pressure they applied to the bio-films, the more resistance the materials put forth, said a U-M release.
The paper will be published in the July 7 edition of Langmuir.
