PubMed: Sensitive determination of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol and complementary cannabinoids in hair using alkaline digestion and mixed-mode solid phase extraction followed by liquid-chromatography-tandem mass spectrometry
Forensic Sci Int. 2021 Oct 6;328:111047. doi: 10.1016/j.forsciint.2021.111047. Online ahead of print.
Hair drug testing can be used for the evaluation of cannabis use with a large detection window, and is required for professional driving license granting in Brazil. A positive hair result for cannabis use requires quantification of the metabolite THC-COOH above the cutoff value of 0.2 ng/g. The achievement of such lower limit of quantification is challenging, particularly with the use of liquid chromatography coupled to triple quadrupole mass spectrometers (LC-MS/MS). In this study, a very sensitive LCMS/ MS assay for the simultaneous quantification of THC-COOH along with THC, CBD, and CBN was developed and validated. Sample preparation was based on hair hydrolysis, followed by selective ion-exchange solid-phase extraction. The extraction yield was 101.5-101.6% for THC-COOH, 92.3-97.4% for THC, 89.7-95.2% for CBN, and 104.9-121.1% for CBD. Internal standard corrected matrix effects were – 2.7 to – 1,1 for THCCOOH and – 11.5 to – 0.1% for the other analytes. The lower limit of quantification was 01 ng/g for THC-COOH and 25 ng/g for THC, CBD, and CBN. The assay fulfilled validation guidelines acceptance criteria. The measurement uncertainties were determined and the assay was ISO17025 accredited, being currently used in routine testing.
#CBD #Hemp https://pubmed.ncbi.nlm.nih.gov/34649099/?utm_source=Chrome&utm_medium=rss&utm_campaign=None&utm_content=1jYCQzi_o_qLYr-oQfnMhShgOXkvGma3vcnBGJtrBhuJMOvEVJ&fc=None&ff=20211015065902&v=2.15.0 October 14, 2021 10:00 am