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Biofilm Control
Microorganisms like bacteria or yeasts hate solitude; they tend to collect in clumps–from a few micrometers to several millimeters in size–called biofilms. This makes them more resistant to cleaning products and antibiotics. In hospital environments, for example, biofilms are the cause of approximately 60% of hospital-acquired infections. To combat these aggregates, Thierry Jouenne’s team in Rouen1,2 has been contributing to some very encouraging tests on a new screening process developed by the start-up company Biofilm Control. This will enable a large-scale screening of different antibiotics to combat the formation of biofilms.
Set up in 2004 by Thierry Bernardi, and based in Clermont-Ferrand, Biofilm Control has developed the Biofilm Ring Test–a simple and rapid method to evaluate the formation of biofilms. Testing is carried out using a 96-well plastic microplate placed on a magnet. A solution of bacteria and magnetizable particles is deposited in each well (the tiny indentations on the plate). If no biofilm is present, the particles submitted to the magnetic field will clump at the bottom of the well and form a spot. But if a biofilm builds up, the particles are gradually immobilized. Fewer particles then react to the magnetic field, the spot is less pronounced and will even disappear when a biofilm has fully formed. The density of the spot is then detected by an appropriate reading device. It is this screening technique that the CNRS researchers are currently experimenting in Rouen.

© Chavant et al (2007) J Microbiol Methos 68:605-612
A solution of bacteria and magnetizable particles is deposited in each well, underneath which a magnet is placed. If no biofilm is present, the particles clump in the center to form a spot detected by a special riding device.
For more information:www.biofilmcontrol.com
1. Laboratoire “Polymères, biopolymères, membranes” (CNRS / Univ. Rouen / INSA Rouen).
2. With INSA in Lyon and the Institut Pasteur in Paris.
Thierry Jouenne
Laboratoire “Polymères, biopolymères, membranes,” Rouen.
thierry.jouenne@univ-rouen.fr