Device that listens to bacteria is here

Here comes a chip that can be used for a most unusual application - the study of signalling in bacterial colonies.

Researchers at Columbia University have developed a chip based on complementary metal-oxide-semiconductor (CMOS) technology that enables them to electrochemically image the signalling molecules from bacteria.

In effect, they have developed chips that 'listen' to bacteria.

"This is an exciting new application for CMOS technology that would provide new insights into how biofilms are formed," said Ken Shepard, professor of electrical engineering and biomedical engineering at Columbia Engineering, Columbia University.

"Disrupting biofilm formation has important implications in public health in reducing infection rates," said Shepard.

This is the first time integrated circuits have been used for such an application - imaging small molecules electrochemically in a multicellular structure.

The team made an integrated circuit, a chip that is an 'active' glass slide - a slide that not only forms a solid-support for the bacterial colony but also 'listens' to the bacteria as they talk to each other.

According to Lars Dietrich, assistant professor of biological sciences at Columbia University, cells mediate their physiological activities using secreted molecules.

The team looked specifically at phenazines which are secreted metabolites that control gene expression.

They found that the bacterial colonies produced a phenazine gradient that is likely to be of physiological significance.

A potential application of this would be to integrate such chips into medical devices that are common sites of biofilm formation, such as catheters, and then use the chips to limit bacterial colonisation.

The next step is to develop a larger chip that would enable larger bacterial colonies to be imaged at higher resolutions, added the study published in the journal Nature Communications.