Dispersive liquid-liquid microextraction of 11-nor-Δ9-tetrahydrocannabinol-carboxylic acid applied to urine testing.

Aim: THC-COOH is the major metabolite of Δ9-tetrahydrocannabinol commonly tested in urine to determine cannabis intake. In this study, a method based on dispersive liquid-liquid microextraction was developed for testing THC-COOH in urine. Materials & methods: Hydrolyzed urine specimens were extracted via dispersive liquid-liquid microextraction with acetonitrile (disperser solvent) and chloroform (extraction solvent). Derivatization was performed with N,O-Bis(trimethylsilyl)trifluoroacetamide with 1% trichloro(chloromethyl)silane. Analysis was performed by GC-MS/MS. Results: The method showed acceptable linearity (5-500 ng/ml), imprecision (<10.5%) and bias (<4.9%). Limits of detection and quantitation were 1 and 5 ng/ml, respectively. Twenty-four authentic samples were analyzed, with 22 samples being positive for THC-COOH. Conclusion: The proposed method is more environmentally friendly and provided good sensitivity, selectivity and reproducibility.

Tweetable abstract Green analytical toxicology: Dispersive liquid­liquid microextraction applied to the analysis of THC-COOH in urine by GC­MS/MS.

Association between travel length and drug use among Brazilian truck drivers.

OBJECTIVE: To investigate whether the use of the stimulants amphetamines and cocaine by truck drivers in Brazil was related to travel length. METHODS: Truck drivers were randomly stopped by the Federal Highway Police on interstate roads in Sao Paulo State during morning hours from 2008 to 2011 and invited to participate in the project "Comandos de Saúde nas Rodovias" (Health Commands on the Roads). Participants were asked about the use of drugs, travel distance, and age, and gender was recorded. Samples of urine were collected and analyzed for amphetamine, benzoylecgonine (a metabolite of cocaine), and carboxytetrahydrocannabinol (THC-COOH; a metabolite of cannabis) by immunological screening and quantification by gas chromatography-mass spectroscopy. RESULTS: Current use of amphetamine, cocaine, and cannabis was reported by 5.7%, 0.7%, and 0.3% of the truck drivers, respectively. Amphetamine, benzoylecgonine, and THC-COOH were found in urine samples from 5.4%, 2.6,% and in 1.0% of the drivers, respectively. There was a significant association between the positive cases for amphetamine and reported travel length; 9.9% of urine samples from drivers who reported travel length of more than 270 km were positive for amphetamine, and 10.9% of those drivers reported current use of amphetamines. In most cases, appetite suppressants containing amphetamines had been used, but the purpose was most often to stay awake and alert while driving. Truck drivers with travel length of more than 270 km had significantly higher odds ratio (OR) for having a urine sample that was positive for amphetamine when adjusted for age as confounding factor (OR = 9.41, 95% confidence interval [CI], 3.97-22.26). No significant association was found between the use of cocaine or cannabis and travel length. CONCLUSION: Truck drivers who reported driving more than 270 km had significantly higher frequencies of urine samples positive for amphetamine and reported significantly more frequent current use of amphetamines than those who reported shorter driving distances.

New catalytic ultrasound method for derivatization of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid in urine, with analysis by GC-MS/MS.

A new procedure is described for the derivatization by silylation of 11-nor-Δ(9)-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) present in urine, followed by analysis using gas chromatography-tandem mass spectrometry. A conventional procedure for derivatization of the analyte was evaluated using two types of experimental design. A 2(3) factorial design considered the parameters temperature, reaction time, and the solvent/derivatization agent ratio. A central composite design (CCD) was applied to optimize the values of the significant variables. The optimum conditions were a reaction temperature of 50 °C, a reaction time of 30 min, and a BSTFA/acetone ratio of 40:20. The use of imidazole as a catalyst, together with ultrasonication, reduced the reaction time to 5 min and increased the efficiency of derivatization of THCCOOH, compared with the conventional method. The operating conditions of the tandem mass spectrometer were also optimized. The method was linear in the concentration range 1-50 ng mL(-1) (R(2) = 0.9951). Intra- and inter-day precisions were 7.7-12.3% and 11.1-13.9%, respectively, recoveries ranged between 91 ± 8% and 101 ± 12%, accuracy (as % bias) was between -11.7% and +0.7%, and limits of detection and quantification were 0.5 and 1.0 ng mL(-1), respectively.

Delirium following ingestion of marijuana present in chocolate cookies.

OBJECTIVE: To describe a case of marijuana-induced delirium and the techniques used to detect psychoactive agents and metabolites in urine. METHODS: A case of delirium following involuntary ingestion of cannabis is described. A urine sample was analyzed applying various chemical procedures, using high-resolution gas chromatography coupled with mass spectrometry technique. 11-Nor-delta9-tetrahydrocannabinol-9-carboxylic acid was quantified by the methodology for steroids and cannabis. RESULTS: A 26-year-old man was hospitalized with severe agitation and psychotic behavior 36 hours after suspected involuntary ingestion of cannabis contained in a brigadeiro, a typical Brazilian cookie, consumed during a party. Treatment with neuroleptics resulted in complete regression of the symptoms over 2 weeks. The urine sample revealed marijuana ingestion, demonstrated by the presence of its metabolite, 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid in high concentration. No other investigated substance was found in the patient's urine. CONCLUSION: Severe delirium can follow oral ingestion of cannabis integrated into homemade cookies.

Identification of 11-Nor-delta9-tetrahydrocannabinol-9-carboxylic acid in urine by ion trap GC-MS-MS in the context of doping analysis.

The purpose of this study is to develop a sensitive and specific alternative to current gas chromatography (GC)-mass spectrometry (MS) selected ion monitoring confirmation methods of 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid (cTHC) in human urine samples, in the context of doping analysis. An identification procedure based on the comparison, among suspicious and control samples, of the relative abundances of cTHC selected product ions obtained by GC-tandem MS in an ion trap is presented. The method complies with the identification criteria for qualitative assays established by sports authorities; the comparison procedure is precise, reproducible, specific, and sensitive, thus indicating that it is fit for the purpose of identification accordingly to World Antidoping Agency requirements.