The technology is cheap, safe and has zero environmental impact. It can be integrated into the electrical grid or powered by batteries.

How does it work

Electric field treatment (CEFT) is used for food pasteurization, but not for disinfection of drinking water due to its high cost. When water and bacteria are exposed to electricity, the bacterial cell membrane acts as a capacitor in the circuit.

• Normally, in conventional electric field processes, due to the low conductivity of water, nanosecond pulses do not charge the membrane fast enough to kill bacteria.
• Researchers created a locally enhanced electric field (LEEFT) that transmits electricity directly to bacteria. The electrodes have gold nano-sized tips that instantly create concentrated charges when connected to electricity, allowing them to travel to the membrane and kill bacteria much faster.

What tests showed

To test the technology, the scientists made a special chip with gold elements on the edge of the electrode and added the test bacterium Staphylococcus, which is often found in water supply systems. The researchers then applied electrical pulses and observed the reaction under a microscope in real time.

Chip with gold element / Photo by GEORGIA TECH

According to the scientists, it was unexpected that bacteria were destroyed so quickly using only nanosecond pulses. Theoretically, the nanosecond pulses are too short to kill bacteria during conventional electric field operation and it takes time to recharge the membrane. But with LEEFT nanostructures, bacterial cells can be directly charged with nanometal, quickly disinfecting water.

Killing bacteria almost instantly reduces the amount of electricity needed to purify water, making it a more affordable option. In the future, clean water production will be less harmful to the environment thanks to this technology.