Search  
DOE Pulse
  • Number 300  |
  • November 23, 2009

Many hands—or many flagella—make light work

In studies of the motion of tiny swimming bacteria, scientists at DOE's Argonne National Laboratory found that the microscopic organisms can stir fluids remarkably quickly and effectively.  As a result, the bacterial flagella could act like tiny motors to mix chemicals in biomedical kits, among other applications.

Igor Aronson, an Argonne materials scientist, and Andrey Sokolov, a former graduate student from the Illinois Institute of Technology and now postdoctoral researcher at Princeton University, piled Bacillus subtillis bacteria into thin films in order to decode the physics that govern how they move. The bacteria, each equipped with many tiny flagella, or tails, shot back and forth across the films.

In the current study, the researchers wanted to see whether the vigorous swimming would mix chemicals evenly throughout the fluid. “They swim so fast that we found no significant gradients of any chemical except oxygen,” Aronson said. And some oxygen mixing did occur: the bacteria improved the diffusion by 100-fold.

[Jared Sagoff, 630.252.5549,
jsagoff@anl.gov]