The emerging field of bioelectrics is marrying two disciplines that, heretofore, have been unaccustomed to each other: high-voltage engineering and cell biology. In this month's feature, "Zap", authors Karl H. Schoenbach, Richard Nuccitelli, and Stephen J. Beebe explain how very powerful but extremely short bursts of electricity offer hope for a possible future form of therapy in treating individuals with cancer and other diseases.
Bioelectrics relies on using pulsed power technology, in which scientists send thousands of amperes of current and just as many volts in nanoseconds through a cell to produce an effect or to observe reactions within the cell's chemical structure. (Ironically, the ability to produce large amounts of power in a jot of time comes from research done on nuclear bomb projects.)
Barely five years old, bioelectrics is finding a growing audience of engineers and scientists investigating it to pursue applications from medicine to weaponry. As the authors relate, the attraction for biologists is potential scientific payoff: these strong but exceedingly brief electric fields act as a kind of electrical probe, letting scientists prod key structures inside cells—making the cells expel certain vital chemicals or begin the production of others—with the aim of understanding basic biological processes. And for engineers, the new field offers the opportunity to forge an important new application of pulsed power technology, which even 10 years ago was seldom used outside the military.
Cells can be thought of as circuits made up of capacitors and resistors. Their membranes and those of their organelles, such as the nucleus, act like capacitors. The briny liquid encased within the membranes is conductive and so it can be thought of as a resistor. In bioelectrics, a powerful jolt is applied to the cell for billionths of a second, which enables the ultrashort voltage pulses to harmlessly slip past a cell's exterior to shock the vital structures within. The authors' research has shown promising results from the technique in curing melanoma in lab mice.
As IEEE Fellow Schoenbach's team at Old Dominion University, in Norfolk, Va., has shown, if you use a pulse generator to subject melanoma tumors to electric fields of 40 kilovolts per centimeter for 300 nanoseconds and you repeat the exposure hundreds of times, you can shrink the tumors and, with repeated therapy, even destroy them completely. The authors admit, though, that biomedical science is littered with cancer cures that work in mice but not in humans. They say it will be many years before we know if bioelectrics will even be worth testing in human subjects.
Still, the prospects appear intriguing, and even at this early stage, they write, bioelectrics seems to offer a totally new therapeutic avenue—one that could lead to a treatment regime free of the debilitating side effects of chemotherapy drugs and the tissue damage of radiation.
We can only offer them, as well as those working on a myriad of applications around the world in the new field, our enthusiastic encouragement. There are enormous numbers of people who could potentially benefit from their research.