The mechanism by which the cavitation, pressure and alcohol combine to kill bacteria remains under study.
"We don't know exactly how the cells die, but we know the end phenomenon," said Donald Ahearn, professor emeritus of biology at Georgia State University. "Increased pressure and disinfectant molecules are somehow enhanced by the cavitation process, but the physiology of the death has yet to be determined."
Ultrasound has been used elsewhere to make skin permeable enough to admit drug compounds. Cunefare suspects that the cavitation may induce a similar effect, making the bacterial cell walls permeable enough to admit the alcohol molecules.
Though the researchers studied only the technique's effect on bacteria, Ahearn -- who did the biological assays for the study -- expects it would also work against viral organisms that can also be troublesome.
The researchers are now seeking support from the National Institutes of Health to optimize the technique, scale it up to a practical size, ensure that it would adequately kill the microorganisms -- and assess the potential for damaging medical instruments.
"We are seeking funding to further develop our understanding of the parameters that affect the transient cavitation," Cunefare explained. "We want to optimize the effects, and explore other additives that might enhance it."
The researchers will also have to improve techniques for coupling power into the fluid in order to treat larger volumes of liquid. Since the amount of energy that can be induced into a liquid depends on the surface area, there may be limits to the volume that can be trea
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Contact: John Toon
john.toon@edi.gatech.edu
404-894-6986
Georgia Institute of Technology Research News
8-Dec-2002