Device detects marijuana intoxication in 3 min
Stanford researchers have developed a mobile device capable of determining whether people are under the influence of marijuana within three minutes. The 'potalyzer' uses magnetic biosensors to detect tetrahydrocannabinol (THC) molecules, the principal psychoactive constituent in marijuana, in saliva. It can also measure THC concentrations in the range of 0-50 nanograms-per-millilitre of saliva.