Determination of cannabinoids in low-volume human whole blood samples by online extraction using turbulent flow chromatography and HRAM Orbitrap MS

20 November 2023

In this application note, Thermo Fisher Scientific discusses the implementation of an analytical method for the specific and sensitive determination of cannabinoids in low-volume human whole blood samples. The method utilizes a Thermo Scientific™ Transcend™ II TLX-1 TurboFlow™ chromatography system coupled to a Thermo Scientific™ Q Exactive™ Focus hybrid quadrupole-Orbitrap™ mass spectrometer. Due to the common recreational use of cannabis, cannabinoids are frequently detected in samples of forensic toxicological interest, such as those related to driving under the influence of drugs, drug-facilitated crimes, or post-mortem toxicology cases.

The traditional analysis of cannabinoids in human whole blood involves time-consuming and expensive steps, including offline liquid-liquid extraction (LLE) or solid phase extraction (SPE), as well as analyte derivatization for gas chromatography-mass spectrometry (GC-MS). The presented method streamlines the process by incorporating online sample clean-up and advanced mass spectrometry techniques. The approach involves the addition of isotopically labeled internal standards (IS), followed by a simple offline protein precipitation step and online extraction using turbulent flow chromatography (Thermo Scientific™ TurboFlow™ technology). Detection is performed using high-resolution, accurate-mass hybrid quadrupole Orbitrap™ mass spectrometry (HRAM Orbitrap MS) in positive/negative switching Selected Ion Monitoring (SIM) acquisition mode. This method is designed to provide a simple, fast, highly specific, and sensitive analytical solution for determining cannabinoids in blood, offering potential benefits for toxicological laboratories.