An artificial ‘nose’ will soon be available for tasks including searching for bombs at airports. This ‘sniffer’, which is a biosensor incorporating antibodies, is being developed by Bofors Applied Technologies, Sweden. The sensor is claimed to be the only artificial nose in the world which can rival a dog’s keen sense of smell.

‘This biosensor will be up to 10,000 times more sensitive than conventional explosives detectors’, says Sten-Anders Brink, the company’s Managing Director.
Modern metal detectors and X-ray cameras are used only for finding weapons, and cannot detect explosives. There are special explosives detectors, but most of them need physical contact with the explosive material and a chemical analysis to determine the substance involved.
‘The portable biosensor can detect amounts as small as a picogram (10-12g — one trillionth of a gram)of explosive from just one air sample’, Brink explains.
The biosensor originates from the need to detect mines, and is claimed to be completely unaffected by interference. It can be used anywhere there is a risk of bomb attack, for example at major events, and in stores, embassies, buses, or trains. Bofors Applied Technologies also claims that another important application will be narcotics detection.
‘Dogs used for finding bombs or narcotics are expensive to buy and train’, explains Brink. ‘The cost of a sensor will be about the same as the annual cost of one dog, but while the dog can work efficiently for only about two hours a day, the sensor can be used continuously’. Market launch is aimed for 1999.

Impossible to fool
Antibodies make up the active part of the sensor, which in principle mimics the body’s immune system.
‘The biosensor reacts only to the substance to be detected’, explains Brink. ‘Antibodies can recognise it even under very difficult conditions, so it’s impossible to fool the sensor’.
The sensor consists of a quartz crystal which oscillates when an electric current is passed across it. The antibodies are located on the crystal. When they come into contact with airborne molecules of the material to be detected, they leave the crystal and bond to the molecules. This changes the mass of the crystal, and hence its fundamental frequency. The change of frequency activates an alarm signal which shows that the substance in question has been detected.
The sensor is developed on the basis of studies of how various smells are recorded in a dog’s brain./ins
Caption:
The biosensor can be used for many tasks, including detecting bombs at airports. It is claimed to be the only artificial nose in the world equal to that of a dog, and is 10,000 times more sensitive than conventional explosives detectors.
For further information please contact:
Sten-Anders Brink, Managing Director
Bofors Applied Technologies AB
SE-691-80 Karlskoga
Sweden
Tel: +46 586 81925
Fax: +46 586 85620
e-mail: sten-anders.brink@bat.bofors.se