Barbiturate detection in oral fluid, plasma, and urine.

BACKGROUND: Although current abuse of barbiturates is low compared with other classes of abused drugs, their narrow margin of safety, risk of dependence, and abuse liability remain a health concern. Limited information is available on the disposition of barbiturates in different biologic matrices. OBJECTIVE: The authors conducted a clinical study of the disposition of barbiturates in oral fluid, plasma, and urine after single-dose administration to healthy subjects. METHODS: Three parallel groups of 15 subjects were administered a single oral dose of one barbiturate: butalbital (50 mg), Phenobarbital (30 mg), or sodium secobarbital (100 mg). Subjects remained at the clinic for two confinement periods; the first was -1 to 36 hours postdose and again at 48 to 52 hours. Oral fluid specimens were collected by bilateral collection (Intercept; one on each side of the mouth simultaneously). Blood specimens were obtained by venipuncture and urine specimens were collected through separate collection pools of varying periods. Oral fluid specimens were analyzed for barbiturates by liquid chromatography-tandem mass spectroscopy with a limit of quantitation of 8 ng/mL. Plasma and urine specimens were analyzed by gas chromatography-mass spectroscopy with a limit of quantitation of 100 ng/mL. RESULTS: Barbiturate side effects included dizziness, drowsiness, and somnolence. All effects resolved spontaneously without medical intervention. The three barbiturates were detectable in oral fluid and plasma within 15 to 60 minutes of administration and in the first urine pooled collection at 2 hours. Butalbital and Phenobarbital remained detectable in all specimens through 48 to 52 hours, whereas secobarbital was frequently negative in the last collection. Oral fluid to plasma ratios appeared stable over the 1- to 48-hour collection period. CONCLUSION: This study demonstrated that single, oral therapeutic doses of butalbital, Phenobarbital, and secobarbital were excreted in readily detectable concentrations in oral fluid over a period of approximately 2 days. Oral fluid patterns of appearance and elimination were similar to that observed for plasma and urine.

Identification and quantitation of amphetamines, cocaine, opiates, and phencyclidine in oral fluid by liquid chromatography-tandem mass spectrometry.

Analytical methods for measuring multiple licit and illicit drugs and metabolites in oral fluid require high sensitivity, specificity, and accuracy. With the limited volume available for testing, comprehensive methodology is needed for simultaneous measurement of multiple analytes in a single aliquot. This report describes the validation of a semi-automated method for the simultaneous extraction, identification, and quantitation of 21 analytes in a single oral fluid aliquot. The target compounds included are amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxy-amphetamine, 3,4-methylenedioxyethylamphetamine, pseudoephedrine, cocaine, benzoylecgonine, codeine, norcodeine, 6-acetylcodeine, morphine, 6-acetylmorphine, hydrocodone, norhydrocodone, dihydrocodeine, hydromorphone, oxycodone, noroxycodone, oxymorphone, and phencyclidine. Oral fluid specimens were collected with the Intercept device and extracted by solid-phase extraction (SPE). Drug recovery from the Intercept device averaged 84.3%, and SPE extraction efficiency averaged 91.2% for the 21 analytes. Drug analysis was performed by liquid chromatography-tandem mass spectrometry in the positive electrospray mode using ratios of qualifying product ions within +/-25% of calibration standards. Matrix ion suppression ranged from -57 to 8%. The limit of quantitation ranged from 0.4 to 5 ng/mL using 0.2 mL of diluted oral fluid sample. Application of the method was demonstrated by testing oral fluid specimens from drug abuse treatment patients. Thirty-nine patients tested positive for various combinations of licit and illicit drugs and metabolites. In conclusion, this validated method is suitable for simultaneous measurement of 21 licit and illicit drugs and metabolites in oral fluid.

Simultaneous analysis of 14 benzodiazepines in oral fluid by solid-phase extraction and LC-MS-MS.

A simple and rapid procedure for the simultaneous screening of 14 benzodiazepines in oral fluid is presented. The procedure involves a solid-phase extraction followed by liquid chromatography-tandem mass spectrometry (LC-MS-MS). The target compounds include diazepam, oxazepam, temazepam, nordiazepam, lorazepam, chlordiazepoxide, alprazolam, alpha-hydroxyalprazolam, desalkylflurazepam, hydroxyethylflurazepam, clonazepam, 7-aminoclonazepam, flunitrazepam, and 7-aminoflunitrazepam. Oral fluid was obtained using a simple device that collects approximately 0.4 mL of oral fluid and dilutes it with 0.8 mL of preservative. The oral fluid sample preparation involves a solid-phase extraction on a Varian Bond Elut cartridge. Quantitation was performed by LC-MS-MS using nordiazepam-d(5) as the internal standard. The extraction efficiency exceeded 83% for all compounds except for 7-aminoclonazepam, which had a recovery of 55%. The limits of quantitation ranged from 0.1 ng/mL to 1.0 ng/mL in the multiple reaction monitoring mode. This method was used to confirm 41 patients that screened positive using the OraSure Technologies Benzodiazepine Intercept MICRO-PLATE Enzyme Immunoassay kit. All screened-positive patients were positive for at least one of the analyzed benzodiazepines, thus showing that this method is suitable for confirmation of the Intercept Benzodiazepine assay.

Passive cannabis smoke exposure and oral fluid testing. II. Two studies of extreme cannabis smoke exposure in a motor vehicle.

Two studies were conducted to determine if extreme passive exposure to cannabis smoke in a motor vehicle would produce positive results for delta-tetrahydrocannabinol (THC) in oral fluid. Passive exposure to cannabis smoke in an unventilated room has been shown to produce a transient appearance of THC in oral fluid for up to 30 min. However, it is well known that such factors as room size and extent of smoke exposure can affect results. Questions have also been raised concerning the effects of tobacco when mixed with marijuana and THC content. We conducted two passive cannabis studies under severe passive smoke exposure conditions in an unventilated eight-passenger van. Four passive subjects sat alongside four active cannabis smokers who each smoked a single cannabis cigarette containing either 5.4%, 39.5 mg THC (Study 1) or 10.4%, 83.2 mg THC (Study 2). The cigarettes in Study 1 contained tobacco mixed with cannabis; cigarettes in Study 2 contained only cannabis. Oral fluid specimens were collected from passive and active subjects with the Intercept Oral Specimen Collection Device for 1 h after smoking cessation while inside the van (Study 1) and up to 72 h (passive) or 8 h (active) outside the van. Additionally in Study 1, Intercept collectors were exposed to smoke in the van to assess environmental contamination during collection procedures. For Study 2, all oral fluid collections were outside the van following smoking cessation to minimize environmental contamination. Oral samples were analyzed with the Cannabinoids Intercept MICRO-PLATE EIA and quantitatively by gas chromatography-tandem mass spectrometry (GC-MS-MS). THC concentrations were adjusted for dilution (x 3). The screening and confirmation cutoff concentrations for THC in neat oral fluid were 3 ng/mL and 1.5 ng/mL, respectively. The limits of detection (LOD) and quantitation (LOQ) for THC in the GC-MS-MS assay were 0.3 and 0.75 ng/mL, respectively. Urine specimens were collected, screened (EMIT, 50 ng/mL cutoff), and analyzed by GC-MS-MS for THCCOOH (LOD/LOQ = 1.0 ng/mL). Peak oral fluid THC concentrations in passive subjects recorded at the end of cannabis smoke exposure were up to 7.5 ng/mL (Study 1) and 1.2 ng/mL (Study 2). Thereafter, THC concentrations quickly declined to negative levels within 30-45 min in Study 1. It was found that environmentally exposed Collectors contained 3-14 ng/mL in Study 1. When potential contamination during collection was eliminated in Study 2, all passive subjects were negative at screening/confirmation cutoff concentrations throughout the study. Oral fluid specimens from active smokers had peak concentrations of THC approximately 100-fold greater than passive subjects in both studies. Positive oral fluid results were observed for active smokers 0-8 h. Urine analysis confirmed oral fluid results. These studies clarify earlier findings on the effects of passive cannabis smoke on oral fluid results. Oral fluid specimens collected in the presence of cannabis smoke appear to have been contaminated, thereby falsely elevating THC concentrations in oral fluid. The risk of a positive test for THC was virtually eliminated when specimens were collected in the absence of THC smoke.