Electrical sense beats drug-driving

You pull over and wind down your window: the policeman asks you to lick a small disposable strip, then plugs it into a handheld meter. In less than a minute you could be arrested if you have been driving under the influence of cannabis or amphetamines.

Professor Richard Compton and Dr Craig Banks in the Department of Chemistry have developed a new electrochemical sensor that can detect traces of drugs in minute quantities of saliva. Their spin-out company OxTox Ltd is developing low-cost, hand-held kits that could become as important in preventing drug-related road deaths as the breathalyser has been against drink-driving.The technology is based on modifying the surfaces of carbon molecules, which can be incorporated into electrodes to provide exquisitely sensitive sensors for a range of targets. A similar approach, using carbon powders, can strip arsenic from contaminated drinking water, a serious problem in some village wells in Bangladesh.