Marijuana is becoming increasingly legal in the United States, but there are limits on its use, just as there are limits on alcohol when driving, for example.
Unlike marijuana, however, there is no quick device for marijuana to check, for example by breathing, the amount taken, as is done with a breathalyzer for alcohol. This is a real problem for the police force and for those in charge of controls in general.
A team of researchers from the Department of Chemistry and the Swanson School of Engineering at the University of Pittsburgh has therefore built one. It is a device that can measure the amount of tetrahydrocannabinol (THC), the active compound present in marijuana itself, by breath alone.
Currently, to check the presence of this compound in the body, analyses of blood, urine or hair samples must be carried out, processes that cannot be carried out naturally, for example, at a checkpoint or at a checkpoint.
The device is constructed with carbon nanotubes capable of capturing the THC molecules present in the breath. Once captured, the surface of the nanotubes changes its electrical properties, which signals the presence of the compound.
These nanotechnological sensors detect THC with a degree of accuracy comparable or even better than mass spectrometers.
In addition, as Sean Hwang, one of the authors of the study as well as the manufacturers of the device, explains, automatic learning technique was also used to “teach” the device to recognize the presence of THC even when there are other imperceptible substances in the breath.
Externally it is similar to a classic breathalyzer: it boasts a plastic casing and mouthpiece plus a small digital display indicating the measurement.