When the water in the rooftop cooling towers of a building's air conditioning system gets infected with Legionella bacteria, people in the building can get potentially-fatal Legionnaires' disease. Therefore, it's important to check that water for the bacteria on a regular basis. A new chip is promised to do it faster than ever.

The typical method of checking for Legionella involves putting a water sample in a Petri dish, then waiting 10 to 14 days to see if any bacterial cultures grow. Unfortunately, populations of Legionella can reach outbreak levels is as short a period as one week. Additionally, if an outbreak has already occurred, then its source needs to be ascertained as fast as possible.

That's why the new LegioTyper chip was created.

Developed at the Technical University of Munich, the inexpensive single-use device contains a microarray of 20 different antibodies. Each one of those binds with a different subtype of Legionella pneumophila, which is the species of Legionella responsible for 80 percent of all infections. If any of those subtypes are present in the water sample, the chip will detect their presence within a claimed 34 minutes – chemicals such as luminol and hydrogen peroxide are used to make them show up by causing a chemiluminescence reaction.

A paper on the research was recently published in the journal Biosensors and Bioelectronics.

And if you just can't wait for the chip to enter production, the commercially-available Spartan Cube is claimed to detect Legionella in 45 minutes.