With just a few drops of saliva and in a few minutes the presence of THC can be detected thanks to a technique developed by the universities of Cordoba and Valencia, making it possible to accelerate the analysis process and to use very small samples.
European universities have developed a new method for quickly and accurately detecting THC in small saliva samples.
This technique simplifies traditional processes into two main steps and utilizes mass spectrometry for rapid analysis. It represents a significant advancement in drug testing technology.
Cannabis is the most widely used illegal drug in Europe. It is estimated that around 8% of adults used cannabis in 2022. Widespread abuse of this substance has health consequences, and is viewed as an important social problem. A fundamental resource to control its use and avoid these health problems would be a quick, simple, non-invasive, and reliable form of analysis that uses a fluid that is easy to extract, such as saliva.
Innovative Saliva-Based Analysis
In order to expedite this type of analysis and make it effective in smaller saliva samples, the FQM-215 – Affordable and Sustainable Sample Preparation group at the University of Cordoba worked together with the GICAPC group at the University of Valencia to design a new analysis technique that simplifies processing of the sample and makes it possible to verify the presence of THC (Tetrahydrocannabinol) with only 0.25 mL of saliva.
Researchers who carried out the study. Credit: University of Cordoba
Dispersive Microextraction Technique
To this end, a technique known as dispersive microextraction by sorption, with a miniaturized stirrer bar, is used, which “consists of the addition of a material capable of extracting the analytes in the sample (in this case, the tetrahydrocannabinol in the saliva), which has magnetic properties, in such a way that when a very small magnet (the stirrer bar) is placed into the device in which the saliva is located, a magnetic agitation occurs causing a vortex to form, dispersing those particles that interact with the analytes in the sample. When the agitation is stopped, the particles with the analytes are attracted to the magnet again,” explained UCO researcher Jaime Millán Santiago.
In this way, the THC molecules in the saliva can be extracted very quickly. “We have reduced to 2 steps what would otherwise be 5,” said UCO professor Marisol Cárdenas.
Streamlined THC Detection
After the sample preparation step comes the second one: “We transfer the miniaturized magnet, coated with the particles that have trapped the THC that was in the sample, and transfer it to a needle, to which we apply a high voltage and add an organic solvent capable of interrupting the interaction between the extractant material and the THC, generating an electrospray that is introduced into the mass spectrometer” the researcher explained.
In just two steps, and with a very small sample of saliva, the concentration of DOI: 10.1021/acs.analchem.4c01297
Discussion about this post