Pathogenic organisms like anthrax could be detected with the help of electric fields, according to a team of workers from the UK.

© iStock

Fatima Labeed at the University of Surrey and a team of researchers have used electrophoresis to separate dangerous bacterial spores from environmental contaminants such as diesel particles. Contamination from environmental particles limits current detection methods, she explained, but this system could be used to detect biowarfare agents in the environment.

The team have developed a device that isolates diesel particles from the bacterium Bacillus subtilis, which is similar to anthrax but less harmful. A dielectrophoretic process, where movement is induced in a particle when it is exposed to a non-uniform electric field, is used to separate a liquid suspension of particles and spores.

The particles are passed through a separation chamber containing microelectrodes. By choosing the right operating conditions the diesel particles are collected at the electrodes in the chamber and the bacterial spores flow out of the chamber.

'This device will be extremely useful for defence organisations, but also has potential for a range of applications, such as public health,' said Labeed. 'In future,' she explained, 'devices such as ours will need to be able to detect very low numbers of bacteria.'

Karel Stulik, of Charles University in Prague, Czech Republic, said that the work 'is a simple and cheap procedure whose application can even be wider than just an indication of a terrorist attack'.

Labeed added that their range will also have to be extended to cover sizes ranging from nano-scale viruses to cells like the water-borne parasite Giardia.

Katherine Davies