A new microfluidic device (for handling small volumes
of fluids) has been developed by researchers to screen for hospital
pathogens like Pseudomonas aeruginosa.
Pseudomonas aeruginosa is a bacterium common in soil and water; it has also been associated with
hospital acquired infections.
People with weakened immune systems are at a particular risk,
especially from the disease cystic fibrosis (the forming thick layers of
mucus in the lungs).
To help the diagnosis of the pathogen, MIT researchers have developed a
new microfluidic device that could speed the monitoring of bacterial
infections associated with cystic fibrosis and other diseases. The
advantage with the device is that it can screen patient samples faster
and with greater accuracy.
The microfluidic chip is etched with tiny channels, each resembling an
elongated hourglass with a pinched midsection. Researchers injected
bacteria through one end of each channel, and observed how bacterial
cells travel from one end to the other. The cells were propelled by
electrical forces. Depending on the type of bacterial cell, they either
passed through the channel's narrow section or were trapped at the
opening. By using this method, the researchers could screen which
bacteria are pathogens and which are harmless.
To
demonstrate the method, the researchers examined ordinary strains of
P. aeruginosa,
along with mutant strains that were missing certain genes required to
make the dangerous pathogens. From their experiments, the researchers
found that their device is able to distinguish benign bacterial cells
from those that are more likely to be pathogenic.
The study was a collaboration between scientists at Ghent University,
Belgium, and the University of Queensland, in Australia. The findings
have been
published
in the journal PLOS One. The paper is called “Dielectrophoresis-Based
Discrimination of Bacteria at the Strain Level Based on Their Surface
Properties.”
Posted by Tim Sandle
