Context
In the last decades, considerable efforts have been extended to develop more effective methods for drug analysis in forensic science. Hair testing is a convenient and non invasive technique for the detection of many controlled drugs and drugs of abuse, with several advantages compared to blood and urine such as a longer window of detection and an easy collection. In cases where hair cannot be collected, nail testing can be a suitable alternative, as it also allows for long term drug analysis. Due to their slower growth, nails can allow for the detection of lower doses, and the absence of melanin can reduce the inter individual variability. While many analytical methods exist for the detection of drugs in hair samples, including cannabinoids, there are still only a few methods to test for the presence of drugs in nail samples, and an even smaller number of methods for the detection of cannabinoids in nail samples. In this study, two methods for the quantification of cannabinoids in hair and nail samples based on liquid chromatography tandem mass spectrometry (LCMS/MS) were developed and validated. The methods were developed for the determination of cannabidiol (CBD), cannabinol (CBN) and Δ Tetrahydrocannabinol (THC) and THC’s main metabolites (11-nor-9-carboxy-THC (THCCOOH), 11-hydroxy-THC (OHTHC), and 8-β-11-dihydroxyTHC (diOHTHC)) and were used to analyze matched hair and nail specimens from 23 cannabis users. The sample preparation protocol consisted of a
decontamination step followed by a pulverization step with the Precellys 24 (Bertin Technologies, Montigny-le-Bretonneux, France) and an alkaline hydrolysis step.
