A new computer chip invented by researchers from Columbia University allows scientists to "listen in" on bacteria, as they exchange information between individual cells. Integrated circuit (IC) technology allows biologists to record images from the bacteria, as well as "listen in" to what they are saying.

Bacteria secrete a variety of chemicals to regulate biological activity between cells. One class of these chemicals are phenazines. They are involved in metabolizing chemicals, directing how genes operate.

Ken Shepard of Columbia Engineering, and assistant professor Lars Dietrich, from Columbia University, led the research. Doctoral students Dan Bellin and Hassan Sakhtah also participated in the study.

"This is an exciting new application... that will provide new insights into how biofilms form," Shepard said.

The team used complementary metal-oxide-semiconductor (CMOS) technology to record signals from bacteria. This is the same electronic switching process used in may digital and analog circuits. Integrated circuits were required to detect chemical signaling between bacterial cells and metabolism, which could not be seen with optical microscopes.

The group studied bacteria living together in a multicellular structure. The team believes this is the first time a serious study has been made on such structures using IC chips.

Researchers believe they may, one day, be able to interrupt communications between bacterial cells. This could provide medical investigators another tool to combat bacterial infections.

"This is a big step forward. We describe using this chip to 'listen in' on conversations taking place in biofilms, but we are also proposing to use it to interrupt these conversations and thereby disrupt the biofilm. In addition to the pure science implications of these studies, a potential application of this would be to integrate such chips into medical devices... and then use the chips to limit bacterial colonization," Dietrich said.

The bacteria examined by the researchers, Pseudomonas aeruginosa, can cause disease in humans and animals. It is found in soil and water throughout the world. Not all bacteria are bad, however. Certain bacteria are essential to the proper functioning of the human body, including digestion.

As a follow-up to this study, the Columbia researchers hope to construct larger chips. These will allow them to examine larger samples, in greater detail than the present study.

Details of the present study were published in the journal Nature Communications.