Several tests can detect cannabis, but saliva is one of the most reliable, efficient, and noninvasive analysis techniques. A study published in Analytical Chemistry featured the design of a new technique that simplifies saliva sample processing and makes it possible to verify the presence of THC (tetrahydrocannabinol) with only 0.25 mL of saliva.
Researchers from the University of Cordoba and the University of Valencia collaborated to develop this new analysis method. The University of Valencia researchers designed the step of extracting and preparing the sample, while the University of Cordoba researchers created this analysis method. Detection can be completed in a short amount of time using just a few drops of saliva.
Extracting and preparing the sample involves a technique known as dispersive microextraction by sorption. A miniaturized stirrer bar consists of a material that facilitates THC extraction from the saliva. THC has magnetic properties, so magnetic agitation occurs when the researchers insert a tiny magnet, such as the stirrer bar, into the saliva sample. The effect is the formation of a vortex that disperses the particles that interact with the analytes or THC in the sample. When the researchers stop the agitation, the particles with the THC are drawn to the magnet again. This step results in fast extraction of the THC molecules in a saliva sample.
The second step involves transferring the coating of particles containing the THC extracted from the sample from the magnet to a needle. The researchers then apply a high voltage and add an organic solvent that potentially interrupts the interaction between the extractant material and the THC. The result is an electrospray introduced into the mass spectrometer that generates an analysis revealing the THC concentration in saliva in minutes. Laboratories can incorporate this advanced detection technology into routine substance use testing.
Sources: Analytical chemistry, Eureka News Alert
