Nanotech bacteria detector

A group of

researchers have developed a novel technique called SEnsing of Phage-Triggered Ion Cascade, or SEPTIC, to rapidly detect and identify bacteria.

Using a nanowell device with two antenna-like electrodes, the scientists can detect the electric-field fluctuations that result when a type of virus called a bacteriophage infects a specific bacterium, and then identify the bacterium present. The researchers tested their technology on strains of E. coli and experienced a 100% success rate in detecting and identifying the bacteria quickly and accurately.

Dr. Laszlo Kish and Dr. Mosong Cheng, both in the Department of Electrical Engineering, collaborated on the work with Dr. Ryland Young and Dr. Maria Dobozi-King, both in the Department of Biochemistry and Biophysics.

The scheme works because only a specific phage can infect a specific bacterium. When a bacteriophage infects a bacterium, the phage injects its DNA into the bacterium and "reprograms" it to produce multiple copies of the phage, called virons. During the infection process, about 100 million ions escape from the host cell. This ion leakage causes fluctuations in the electric field around the bacterium, and the nanowell developed by Cheng detects these fluctuations.