A team of Swinburne University of
Technology researchers has shown that low-temperature microwaves can be used to
open up pores in bacterial cells, which could lead to significant improvements
in the design of drug delivery systems.
The study, co-authored by Dean of
Swinburne’s Faculty of Life and Social Sciences Professor Russell Crawford, has
been published in Applied and Environmental Microbiology and
highlighted by Microbes.
According to Professor Crawford the
research conducted by the faculty’s Nano-BioTech Group showed that, when
exposed to an 18 GHz radiofrequency electromagnetic field, E. coli cells ingested sugar molecules from the solution
surrounding them.
“This showed us that the microwave
treatment was opening up pores in the bacterial cells, allowing sugar molecules
to cross the cellular membrane.”
Scientists have long debated whether
microwave frequency exposure can affect bacterial cells independent of
microwave-associated temperature increases.
By conducting the experiments at
lower peak temperatures—between 20 and 40 degrees—the researchers were able
show that it was a specific bioeffect caused by the electromagnetic field
exposure, rather than high temperatures, which caused changes to the bacterial
cells.
This also meant that the researchers
were able to induce pores in the bacterial cells without causing any heat damage.
According to Crawford, this has great potential for research and medical
applications.
“For instance, the pore-forming
effect could help doctors deliver antibiotics to infection sites, such as open
wounds or surfaces around medical implants,” he says.
“By focusing microwave treatment on
the site, this would open up pores in the bacterial cells allowing the drugs to
enter. And because the microwave treatment would be done at a low temperature
it wouldn’t damage any of the patient’s surrounding cells.”
While work still needs to be done to
incorporate the researchers’ findings into a drug delivery system, discovery of
the novel pore-forming effect is a significant first step.
