The present work describes the validation of a novel aqueous in situ derivatization procedure with trimethyloxonium tetrafluoroborate (TMO) as methylating agent for the simultaneous, quantitative analysis of Δ9-tetrahydrocannabinol (THC) and 11-nor-Δ9-tetrahydrocannabinol carboxylic acid (THC-COOH) in human urine. The derivatizing agent is directly added to the urine sample and the methyl-derivatives are then recovered by liquid–liquid extraction procedure. Gas chromatography–mass spectrometry was used to detect the derivatives in selected ion monitoring mode. The limits of detection were 0.7 ng/mL for THC and 0.5 ng/mL for THC-COOH, whereas the limits of quantification were 1.9 and 0.9 ng/mL, respectively. The method has been applied to 60 real samples both positive and negative to immunochemical screening test resulting to be very useful and reliable in routine analysis of THC-COOH in human urine for toxicological and forensic purposes.
Novel Method for Simultaneous Aqueous in Situ Derivatization of THC and THC-COOH in Human Urine Samples: Validation and Application to Real Samples
Chericoni S;GIUSIANI, MARIO
2011-01-01
Abstract
The present work describes the validation of a novel aqueous in situ derivatization procedure with trimethyloxonium tetrafluoroborate (TMO) as methylating agent for the simultaneous, quantitative analysis of Δ9-tetrahydrocannabinol (THC) and 11-nor-Δ9-tetrahydrocannabinol carboxylic acid (THC-COOH) in human urine. The derivatizing agent is directly added to the urine sample and the methyl-derivatives are then recovered by liquid–liquid extraction procedure. Gas chromatography–mass spectrometry was used to detect the derivatives in selected ion monitoring mode. The limits of detection were 0.7 ng/mL for THC and 0.5 ng/mL for THC-COOH, whereas the limits of quantification were 1.9 and 0.9 ng/mL, respectively. The method has been applied to 60 real samples both positive and negative to immunochemical screening test resulting to be very useful and reliable in routine analysis of THC-COOH in human urine for toxicological and forensic purposes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
