Quantitative analysis of delta9-tetrahydrocannabinol in preserved oral fluid by liquid chromatography-tandem mass spectrometry

A rapid and sensitive method for the analysis of delta9-tetrahydrocannabinol (THC) in preserved oral fluid was developed and fully validated. Oral fluid was collected with the Intercept, a Food and Drug Administration (FDA) approved sampling device that is used on a large scale in the U.S. for workplace drug testing. The method comprised a simple liquid-liquid extraction with hexane, followed by liquid chromatography-tandem mass spectrometry (LC-MS-MS) analysis. Chromatographic separation was achieved using a XTerra MS C18 column, eluted isocratically with 1 mM ammonium formate-methanol (10:90, v/v). Selectivity of the method was achieved by a combination of retention time, and two precursor-product ion transitions. The use of the liquid-liquid extraction was demonstrated to be highly effective and led to significant decreases in the interferences present in the matrix. Validation of the method was performed using both 100 and 500 MicroL of oral fluid. The method was linear over the range investigated (0.5-100 ng/mL and 0. 1-10 ng/mL when 100 and 500 microL, respectively, of oral fluid were used) with an excellent intra-assay and inter-assay precision (relative standard deviations, RSD <6%) for quality control samples spiked at a concentration of 2.5 and 25 ng/mL and 0.5 and 2.5 ng/mL, respectively. Limits of quantification were 0.5 and 0.1 ng/mL when using 100 and 500 microL, respectively. In contrast to existing GC-MS methods, no extensive sample clean-up and time-consuming derivatisation steps were needed. The method was subsequently applied to Intercept samples collected at the roadside and collected during a controlled study with cannabis.     

Fluorescence‐based lateral flow assays for rapid oral fluid roadside detection of cannabis use

With the recent worldwide changes in the legalization of marijuana, there is a significant need for rapid, roadside screening test for driving under the influence of drugs. A robust, sensitive, lateral flow assay has been developed to detect recent use via oral‐fluid testing for Δ⁹‐tetrahydrocannabinol (THC). This proof‐of‐concept assay uses a fluorescent‐based immunoassay detection of polymeric beads, conjugated to antibodies against native THC. The fluorescent technique allows for significantly lower limits of detection and higher precision determination of recent marijuana use without the use of urine or blood sampling—thus allowing for roadside identification. Detection levels of 0.01 ng/mL were distinguished from background and the lower limit of quantification was determined to approach 1 ng/mL.     

Determination of amphetamine-type stimulants, cocaine and ketamine in human hair by liquid chromatography/linear ion trap-Orbitrap hybrid mass spectrometry

An LTQ Orbitrap XL hybrid mass spectrometry method was developed for the determination of illicit drugs and their metabolites, including amphetamine (AP), methamphetamine (MA), dimethylamphetamine (DMA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), ketamine (KET), norketamine (NK), cocaine (COC) and benzoylecgonine (BE), in hair. Micropulverized extraction was employed for sample preparation using a small hair sample (2 cm piece or 0.2 mg). Recoveries of the analytes during sample preparation were estimated using fortified hair samples and ranged from 35.5% for COC to 71.7% for AP. High resolution full-scan mass spectra and unit resolution product-ion spectra were obtained with the Orbitrap analyzer and the linear ion-trap analyzer, respectively. High-resolution extracted ion chromatograms at a tolerance of 3 ppm were utilized for quantification. The analytes were identified using the product-ion spectra in combination with the accurate masses of the corresponding protonated molecules observed in the high-resolution mass spectra. Lower limits of quantification obtained from a 0.2 mg hair sample were 0.050 ng mg(-1) (MDMA, KET and BE), 0.10 ng mg(-1) (AP, MA, DMA, NK and COC) and 0.50 ng mg(-1) (MDA). Two reference materials were analyzed for verification, and segmental analysis of single strands of hair specimens from actual cases was performed.     

A semi‐automated solid‐phase extraction liquid chromatography/tandem mass spectrometry method for the analysis of tetrahydrocannabinol and metabolites in whole blood

Marijuana is one of the most commonly abused illicit substances in the USA, making cannabinoids important to detect in clinical and forensic toxicology laboratories. Historically, cannabinoids in biological fluids have been derivatized and analyzed by gas chromatography/mass spectrometry (GC/MS). There has been a gradual shift in many laboratories towards liquid chromatography/mass spectrometry (LC/MS) for this analysis due to its improved sensitivity and reduced sample preparation compared with GC/MS procedures. This paper reports a validated method for the analysis of Δ⁹‐tetrahydrocannabinol (THC) and its two main metabolites, 11‐nor‐9‐carboxy‐Δ⁹‐tetrahydrocannabinol (THC‐COOH) and 11‐hydroxy‐Δ⁹‐tetrahydrocannabinol (THC‐OH), in whole blood samples. The method has also been validated for cannabinol (CBD) and cannabidiol (CDN), two cannabinoids that were shown not to interfere with the method. This method has been successfully applied to samples both from living people and from deceased individuals obtained during autopsy. This method utilizes online solid‐phase extraction (SPE) with LC/MS. Pretreatment of samples involves protein precipitation, sample concentration, ultracentrifugation, and reconstitution. The online SPE procedure was developed using Hysphere C8‐EC sorbent. A chromatographic gradient with an Xterra MS C₁₈ column was used for the separation. Four multiple‐reaction monitoring (MRM) transitions were monitored for each analyte and internal standard. Linearity generally fell between 2 and 200 ng/mL. The limits of detection (LODs) ranged from 0.5 to 3 ng/mL and the limits of quantitation (LOQs) ranged from 2 to 8 ng/mL. The bias and imprecision were determined using a simple analysis of variance (ANOVA: single factor). The results demonstrate bias as <7%, and imprecision as <9%, for all components at each quantity control level. Published in 2009 by John Wiley & Sons, Ltd.     

UHPLC-ESI-MS/MS method for direct analysis of drugs of abuse in oral fluid for DUID assessment

An ultra-high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry method for the direct analysis in oral fluid (OF) of several abused drugs and metabolites in a single chromatographic run was set up and validated. Amphetamine, methamphetamine, morphine, O-6-monoacetylmorphine, cocaine, codeine, methylenedioxymethamphetamine (MDMA), methylenedioxyethylamphetamine, methylenedioxyamphetamine, methadone, benzoylecgonine (BEG), Δ9-tetrahydrocannabinol (THC), ketamine, and cocaethylene were determined in a single chromatographic run with no sample pretreatment, after addition of the respective deuterated internal standards. The method was designed to perform a confirmation analysis on the residual OF samples after the preliminary on-site screening test, and it was applied on preservative buffers from different devices (Mavand Rapidstat, Concateno DDS, and Greiner Bio-One) or on neat OF samples. The method was suitable to be applied to the small amounts of sample available for the confirmatory analysis after the preliminary on-site screening or on undiluted OF samples. Limits of detection varied from 5 (morphine) to 0.2 ng/mL (methamphetamine, MDMA, BEG, and cocaethylene). The method was linear for all the substances involved, giving quadratic correlation coefficients of >0.99 in all the different preservative buffers checked. In addition, repeatability and accuracy were satisfactory for the majority of the substances, except for a few cases. The developed method was subsequently applied to 466 residual samples from on-site screening performed by police officers. Of these samples, 74 showed the presence of cocaine and metabolites; THC was detected in 49 samples. Two samples showed codeine and morphine while MDMA was detected in 11 samples and ketamine in four samples.     

Liquid chromatography/tandem mass spectrometry for the qualitative and quantitative analysis of illicit drugs and medicines in preserved oral fluid

A qualitative and quantitative analytical method was developed for the simultaneous determination of 24 illicit drugs and medicines, in preserved oral fluid samples collected with the StatSure Saliva Sampler? collection device. The samples were prepared by liquid‐liquid extraction followed by liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis. The chromatographic separation was performed with an Atlantis T3 (100 × 2.1 mm i.d., 3 µm) reversed‐phase column using an acetonitrile/2 mM ammonium formate buffer pH 3.4 gradient and the MS/MS detection was achieved with two precursor‐product ion transitions per substance. The method was fully validated, including specificity and capacity of identification, limit of detection (0.2–2.1 µg/L), limit of quantitation (0.8–6.4 µg/L), recovery (34–98%), carryover, linearity (the method was linear in the range 1–200 µg/L), intra‐assay precision (coefficient of variance (CV) <20% for 20 µg/L and CV <10% for 100 µg/L) and inter‐assay accuracy (mean relative error <15%) and precision (CV <20%). The method showed to be specific and sensitive. It has already been successfully used in four proficiency tests and subsequently applied to oral fluid samples collected from road traffic volunteers in the driving population of Portugal (districts of Lisbon, Coimbra and Porto), within the DRUID project. Copyright © 2009 John Wiley & Sons, Ltd.     

An analytical approach for on-site analysis of breath samples for Δ9-tetrahydrocannabinol (THC)

Increased acceptance of cannabis containing the psychoactive component, Δ9-tetrahydrocannabinol (THC), raises concerns about the potential for impaired drivers and increased highway accidents. In contrast to the “breathalyzer” test, which is generally accepted for determining the alcohol level in a driver, there is no currently accepted roadside test for THC in a motorist. There is a need for an easily collectible biological sample from a potentially impaired driver coupled with an accurate on-site test to measure the presence and quantity of THC in a driver. A novel breath collection device is described, which includes three separate sample collectors for collecting identical A, B, and C breath samples from a subject. A simple one-step ethanol extraction of the “A” breath collector sample can be analyzed by UHPLC/selected ion monitoring (SIM) liquid chromatography/mass spectrometry (LC/MS) to provide qualitative and quantitative determination of THC in breath sample in less than 4 min for samples collected up to 6 h after smoking a cannabis cigarette. SIM LC/MS bioanalyses employed d3-THC as the stable isotope internal standard fortified in negative control breath samples for quantitation including replicates of six calibrator standards and three quality control (QC) samples. Subsequent confirmation of the same breath sample in the B collectors was then confirmed by a reference lab by LC/MS/MS analysis. Fit-for-purpose bioanalytical validation consistent with pharmaceutical regulated bioanalyses produced pharmacokinetic (PK) curves for the two volunteer cannabis smokers. These results produced PK curves, which showed a rapid increase of THC in the breath of the subjects in the first hour followed by reduced THC levels in the later time points. A simpler single-point calibration curve procedure with calibrators and QC prepared in ethanol provided similar results. Limitations to this approach include the higher cost and operator skill sets for the instrumentation employed and the inability to actually determine driver impairment.     

Rapid drug-screening of clandestine tablets by MALDI-TOF mass spectrometry

A novel method for the rapid screening of clandestine tablets for drugs by MALDI-TOF mass spectrometry is described. In this method, cetrimonium bromide (CTAB), a surfactant, is added to the conventional α-cyano-4-hydroxycinnamic acid (CHCA) matrix solution used in preparing the MALDI samples. This procedure allows very clean mass spectra to be collected for amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), caffeine, ketamine and tramadol. The method was used successfully in the rapid drug-screening of some actual clandestine tablets, which had been seized from the illicit market, and can serve as a good complementary method to GC/MS for use in forensic analysis.     

Rapid screening of methamphetamines in human serum by headspace solid-phase microextraction using a dodecylsulfate-doped polypyrrole film coupled to ion mobility spectrometry

A simple, rapid and highly sensitive method for simultaneous analysis of methamphetamine (MA) and 3,4-methylenedioxy methamphetamine (MDMA) in human serum was developed using the solid-phase microextraction (SPME) combined with ion mobility spectrometry (IMS). A dodecylsulfate-doped polypyrrole (PPy-DS) was applied as a new fiber for SPME. Electrochemically polymerized PPy is formed on the surface of a platinum wire and will contain charge-compensating anion (dodecylsulfate) incorporated during synthesis using cyclic voltammetry (CV) technique. The extraction properties of the fiber to MA and MDMA were examined, using a headspace-SPME (HS-SPME) device and thermal desorption in injection port of IMS. The results show that PPy-DS as a SPME fiber coating is suitable for the successful extraction of these compounds. This method is suitable for the identification and determination of MAs, is not time-consuming, requires small quantities of sample and does not require any derivatization. Parameters like pH, extraction time, ionic strength, and temperature of the sample were studied and optimized to obtain the best extraction results. The HS-SPME-IMS method provided good repeatability (RSDs<7.8 %) for spiked serum samples. The calibration graphs were linear in the range of 20-4000 ng ml(-1) (R(2)>0.99) and detection limits for MDMA and MA were 5 and 8 ng ml(-1), respectively. HS-SPME-IMS of non-spiked serum sample provided a spectrum without any peak from the matrix, supporting an effective sample clean-up. Finally, the proposed method was applied for analysis one of the ecstasy tablet.     

Roadside Drug Testing Approaches

The purpose of this review is to present an overview of roadside drug testing, driving enforcement, and drunk/drug driving detection around the world. Drunk and drug driving is a severe problem, not only in the UAE, but also around the world. This has important implications for road safety as drunk or drug driving may increase the chances of a driver’s involvement in a road crash when compared to a drug-free driver. Recently, due to increases in drug-impaired drivers’ crash involvement, many mobile roadside drug testing devices have been introduced to the market. These devices use oral fluid, urine or blood matrices. These are on-the-spot tests, which are easy to use and are applied by law enforcement agencies and the public. Law enforcement agencies most commonly use oral fluid to detect the presence of illicit drugs in drivers. This review discusses all the available devices in the market used by the authorities. It also describes the type of drugs widely abused by drivers along with behavioral testing methods. The different types of matrices used for roadside drug testing are also evaluated. Sample collection, storage, and pre-treatment methods are discussed, followed by the confirmatory analysis of positive samples. This article will significantly help law enforcement agencies compare and evaluate all the reliable roadside testing devices and new emerging confirmatory devices available to them in the market. This will help them make an informed decision on which device to adapt to their individual needs.     

Studies on the metabolism of the Δ9‐tetrahydrocannabinol precursor Δ9‐tetrahydrocannabinolic acid A (Δ9‐THCA‐A) in rat using LC‐MS/MS,LC‐QTOF MS and GC‐MS techniques

In Cannabis sativa, Δ9‐Tetrahydrocannabinolic acid‐A (Δ9‐THCA‐A) is the non‐psychoactive precursor of Δ9‐tetrahydrocannabinol (Δ9‐THC). In fresh plant material, about 90% of the total Δ9‐THC is available as Δ9‐THCA‐A. When heated (smoked or baked), Δ9‐THCA‐A is only partially converted to Δ9‐THC and therefore, Δ9‐THCA‐A can be detected in serum and urine of cannabis consumers. The aim of the presented study was to identify the metabolites of Δ9‐THCA‐A and to examine particularly whether oral intake of Δ9‐THCA‐A leads to in vivo formation of Δ9‐THC in a rat model. After oral application of pure Δ9‐THCA‐A to rats (15 mg/kg body mass), urine samples were collected and metabolites were isolated and identified by liquid chromatography‐mass spectrometry (LC‐MS), liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) and high resolution LC‐MS using time of flight‐mass spectrometry (TOF‐MS) for accurate mass measurement. For detection of Δ9‐THC and its metabolites, urine extracts were analyzed by gas chromatography‐mass spectrometry (GC‐MS). The identified metabolites show that Δ9‐THCA‐A undergoes a hydroxylation in position 11 to 11‐hydroxy‐Δ9‐tetrahydrocannabinolic acid‐A (11‐OH‐Δ9‐THCA‐A), which is further oxidized via the intermediate aldehyde 11‐oxo‐Δ9‐THCA‐A to 11‐nor‐9‐carboxy‐Δ9‐tetrahydrocannabinolic acid‐A (Δ9‐THCA‐A‐COOH). Glucuronides of the parent compound and both main metabolites were identified in the rat urine as well. Furthermore, Δ9‐THCA‐A undergoes hydroxylation in position 8 to 8‐alpha‐ and 8‐beta‐hydroxy‐Δ9‐tetrahydrocannabinolic acid‐A, respectively, (8α‐Hydroxy‐Δ9‐THCA‐A and 8β‐Hydroxy‐Δ9‐THCA‐A, respectively) followed by dehydration. Both monohydroxylated metabolites were further oxidized to their bishydroxylated forms. Several glucuronidation conjugates of these metabolites were identified. In vivo conversion of Δ9‐THCA‐A to Δ9‐THC was not observed. Copyright © 2009 John Wiley & Sons, Ltd.     

Matrix effect in bio-analysis of illicit drugs with LC-MS/MS: Influence of ionization type, sample preparation, and biofluid

The purpose of the present work was to evaluate the synergistic effect of ionization type, sample preparation technique, and bio-fluid on the presence of matrix effect in quantitative liquid chromatography (LC)-MS/MS analysis of illicit drugs by post-column infusion experiments with morphine (10-microg/mL solution). Three bio-fluids (urine, oral fluid, and plasma) were pretreated with four sample preparation procedures [direct injection, dilution, protein precipitation, solid-phase extraction (SPE)] and analyzed by both LC-electrospray ionization (ESI)-MS/MS and LC-atmospheric pressure chemical ionization (APCI)-MS/MS. Our results indicated that both ionization types showed matrix effect, but ESI was more susceptible than APCI. Sample preparation could reduce (clean up) or magnify (pre-concentrate) matrix effect. Residual matrix components were specific to each bio-fluid and interfered at different time points in the chromatogram. We evaluated matrix effect in an early stage of method development and combined optimal ionization type and sample preparation technique for each bio-fluid. Simple dilution of urine was sufficient to allow for the analysis of the analytes of interest by LC-APCI-MS/MS. Acetonitrile protein precipitation provided both sample clean up and concentration for oral fluid analysis, while SPE was necessary for extensive clean up of plasma prior to LC-APCI-MS/MS.     

Rapid,simple, and highly sensitive analysis of drugs in biological samples using thin-layer chromatography coupled with matrix-assisted laser desorption/ionization mass spectrometry

Rapid and precise identification of toxic substances is necessary for urgent diagnosis and treatment of poisoning cases and for establishing the cause of death in postmortem examinations. However, identification of compounds in biological samples using gas chromatography and liquid chromatography coupled with mass spectrometry entails time-consuming and labor-intensive sample preparations. In this study, we examined a simple preparation and highly sensitive analysis of drugs in biological samples such as urine, plasma, and organs using thin-layer chromatography coupled with matrix-assisted laser desorption/ionization mass spectrometry (TLC/MALDI/MS). When the urine containing 3,4-methylenedioxymethamphetamine (MDMA) without sample dilution was spotted on a thin-layer chromatography (TLC) plate and was analyzed by TLC/MALDI/MS, the detection limit of the MDMA spot was 0.05 ng/spot. The value was the same as that in aqueous solution spotted on a stainless steel plate. All the 11 psychotropic compounds tested (MDMA, 4-hydroxy-3-methoxymethamphetamine, 3,4-methylenedioxyamphetamine, methamphetamine, p-hydroxymethamphetamine, amphetamine, ketamine, caffeine, chlorpromazine, triazolam, and morphine) on a TLC plate were detected at levels of 0.05 − 5 ng, and the type (layer thickness and fluorescence) of TLC plate did not affect detection sensitivity. In addition, when rat liver homogenate obtained after MDMA administration (10 mg/kg) was spotted on a TLC plate, MDMA and its main metabolites were identified using TLC/MALDI/MS, and the spots on a TLC plate were visualized by MALDI/imaging MS. The total analytical time from spotting of intact biological samples to the output of analytical results was within 30 min. TLC/MALDI/MS enabled rapid, simple, and highly sensitive analysis of drugs from intact biological samples and crude extracts. Accordingly, this method could be applied to rapid drug screening and precise identification of toxic substances in poisoning cases and postmortem examinations.     

Exploring the chemical profile of designer drugs by ESI(+) and PSI(+) mass spectrometry—An approach on the fragmentation mechanisms and chemometric analysis

The consumption of design drugs, frequently known as new psychoactive substances (NPS), has increased considerably worldwide, becoming a severe issue for the responsible governmental agencies. These illicit substances can be defined as synthetic compounds produced in clandestine laboratories in order to act as analogs of schedule drugs mimetizing its chemical structure and improving its pharmacological effects while hampering the control and making regulation more complicated. In this way, the development of new methodologies for chemical analysis of NPS drugs is indispensable to determine a novel class of drugs arising from the underground market. Therefore, this work shows the use of high‐resolution mass spectrometry Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS) applying different ionization sources such as paper spray ionization (PSI) and electrospray ionization (ESI) in the evaluation of miscellaneous of seized drugs samples as blotter paper (n = 79) and tablet (n = 100). Also, an elucidative analysis was performed by ESI(+)MS/MS experiments, and fragmentation mechanisms were proposed to confirm the chemical structure of compounds identified. Besides, the results of ESI(+) and PSI(+)‐FT‐ICR MS were compared with those of GC–MS, revealing that ESI(+)MS showed greater detection efficiency among the methodologies employed in this study. Moreover, this study stands out as a guide for the chemical analysis of NPS drugs, highlighting the differences between the techniques of ESI(+)‐FT‐ICR MS, PSI(+)‐FT‐ICR MS, and GC–MS.     

Analytical evaluation of a rapid on-site oral fluid drug test

There is a need for a reliable rapid on-site oral fluid test that can be used in police controls to detect impaired drivers. We evaluated the Varian Oralab®6 and collected two oral fluid samples from 250 subjects, one with the Varian Oralab®6 and one with the StatSure? Saliva?Sampler?. The Oralab®6 can detect six drug types: amphetamines, methamphetamine, cocaine, opiates, delta9-tetrahydrocannabinol (THC), and phencyclidine (PCP). On-site results were obtained within 10 to 15 min. The sample collected with StatSure? was analyzed using liquid chromatography–tandem mass spectrometry after liquid–liquid extraction and these results were used as a reference to determine prevalence, sensitivity, and specificity. Two cut-off values were used in the evaluation. The Varian cut-off values were: amphetamine 50 ng/mL, cocaine 20 ng/mL, opiates 40 ng/mL, and THC 50 ng/mL. The DRUID cut-offs were: amphetamine 25 ng/mL, cocaine 20 ng/mL, opiates 20 ng/mL, and THC 1 ng/mL. Applying the first cut-offs, prevalence, sensitivity, and specificity were: amphetamine 10%, 76%, 100%; cocaine 23%, 34%, 100%; opiates 38%, 83%, 94%; and THC 18%, 41%, 99%. The DRUID cut-off values gave the following results: amphetamine 14%, 56%, 100%; cocaine 28%, 34%, 100%; opiates 49%, 68%, 98%, and THC 45%, 16%, 99%. The specificity of the Oralab®6 is generally good. For both cut-offs, sensitivity was low for cocaine and THC. Therefore, the Varian Oralab®6 test is not sensitive enough to be applied during roadside police controls.     

Detection and identification of 700 drugs by multi-target screening with a 3200 Q TRAP® LC-MS/MS system and library searching

The multi-target screening method described in this work allows the simultaneous detection and identification of 700 drugs and metabolites in biological fluids using a hybrid triple-quadrupole linear ion trap mass spectrometer in a single analytical run. After standardization of the method, the retention times of 700 compounds were determined and transitions for each compound were selected by a “scheduled” survey MRM scan, followed by an information-dependent acquisition using the sensitive enhanced product ion scan of a Q TRAP^® hybrid instrument. The identification of the compounds in the samples analyzed was accomplished by searching the tandem mass spectrometry (MS/MS) spectra against the library we developed, which contains electrospray ionization–MS/MS spectra of over 1,250 compounds. The multi-target screening method together with the library was included in a software program for routine screening and quantitation to achieve automated acquisition and library searching. With the help of this software application, the time for evaluation and interpretation of the results could be drastically reduced. This new multi-target screening method has been successfully applied for the analysis of postmortem and traffic offense samples as well as proficiency testing, and complements screening with immunoassays, gas chromatography–mass spectrometry, and liquid chromatography–diode-array detection. Other possible applications are analysis in clinical toxicology (for intoxication cases), in psychiatry (antidepressants and other psychoactive drugs), and in forensic toxicology (drugs and driving, workplace drug testing, oral fluid analysis, drug-facilitated sexual assault).     

Direct Mass Spectrometry Analysis of Biofluid Samples Using Slug‐Flow Microextraction Nano‐Electrospray Ionization

Direct mass spectrometry (MS) analysis of biofluids with simple procedures represents a key step in the translation of MS techniques to clinical and point‐of‐care applications. The current study reports the development of a single‐step method using slug‐flow microextraction and nano‐electrospray ionization for MS analysis of organic compounds in blood and urine. High sensitivity and quantitation precision have been achieved in the analysis of therapeutic and illicit drugs in 5 μL samples. Real‐time chemical derivatization has been incorporated for analyzing anabolic steroids. The monitoring of enzymatic functions has also been demonstrated with cholinesterase in wet blood. The reported study encourages the future development of disposable cartridges, which function with simple operation to replace the traditional complex laboratory procedures for MS analysis of biological samples.     

Qualitative and quantitative analysis of THC, 11‐hydroxy‐THC and 11‐nor‐9‐carboxy‐THC in whole blood by ultra‐performance liquid chromatography/tandem mass spectrometry

A qualitative and quantitative analytical method was developed for the simultaneous determination of Δ⁹‐tetrahydrocannabinol (THC), 11‐hydroxy‐Δ⁹‐tetrahydrocannabinol (11‐OH‐THC) and l1‐nor‐9‐carboxy‐Δ⁹‐tetrahydrocannabinol (THC‐COOH) in whole blood. The samples were prepared by solid‐phase extraction followed by ultra‐performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) analysis using positive ion electrospray ionization and multiple reaction monitoring. The chromatographic separation was performed with an Acquity UPLC® HSS T3 (50 × 2.1 mm i.d., 1.8 µm) reversed‐phase column using a methanol/2 mM ammonium formate (formic acid 0.1%) gradient in a total run time of 9.5 min. MS/MS detection was achieved with two precursor‐product ion transitions per substance. The method was fully validated, including selectivity and capacity of identification, according to the identification criteria (two transitions per substance, signal‐to‐noise ratio, relative retention time and ion ratio) without the presence of interferences, limit of detection (0.2 µg/L for THC and 0.5 µg/L for 11‐OH‐THC and THC‐COOH), limit of quantitation (0.5 µg/L for all cannabinoids), recovery (53–115%), carryover, matrix effect (34‐43%), linearity (0.5‐100 µg/L), intra‐assay precision (CV < 10% for the relative peak area ratios and <0.1% for the relative retention time), inter‐assay accuracy (mean relative error <10%) and precision (CV <11%). The method has already been successfully used in proficiency tests and subsequently applied to authentic samples in routine forensic analysis. Copyright © 2011 John Wiley & Sons, Ltd.     

Supercritical fluid chromatography coupled with tandem mass spectrometry: A high‐efficiency detection technique to quantify Taxane drugs in whole‐blood samples

We present a technique to rapid determine taxane in blood samples by supercritical fluid chromatography together with mass spectrometry. The aim of this study was to develop a supercritical fluid chromatography with mass spectrometry method for the analysis of paclitaxel, cabazitaxel, and docetaxel in whole‐blood samples of rats. Liquid‐dry matrix spot extraction was selected in sample preparation procedure. Supercritical fluid chromatography separation of paclitaxel, cabazitaxel, docetaxel, and glyburide (internal standard) was accomplished within 3 min by using the gradient mobile phase consisted of methanol as the compensation solvent and carbon dioxide at a flow rate of 1.0 mL/min. The method was validated regarding specificity, the lower limit of quantification, repeatability, and reproducibility of quantification, extraction recovery, and matrix effects. The lower limit of quantification was found to be 10 ng/mL since it exhibited acceptable precision and accuracy at the corresponding level. All interday accuracies and precisions were within the accepted criteria of ±15% of the nominal value and within ±20% at the lower limit of quantification, implying that the method was reliable and reproducible. In conclusion, this method is a promising tool to support and improve preclinical or clinical pharmacokinetic studies with the taxanes anticancer drugs.     

Simultaneous quantitative determination of amphetamines, ketamine, opiates and metabolites in human hair by gas chromatography/mass spectrometry

A gas chromatography/mass spectrometry (GC/MS) method was developed and validated for the determination of common drugs of abuse in Asia. The method was able to simultaneously quantify amphetamines (amphetamine; AP, methamphetamine; MA, methylenedioxy amphetamine; MDA, methylenedioxymeth mphetamine; MDMA, methylenedioxy ethylamphetamine; MDEA), ketamine (ketamine; K, norketamine; NK), and opiates (morphine; MOR, codeine; COD, 6-acetylmorphine; 6-AM) in human hair. Hair samples (25 mg) were washed, cut, and incubated overnight at 25 degrees C in methanol/trifluoroacetic acid (methanol/TFA). The samples were extracted by solid-phase extraction (SPE), derivatized using heptafluorobutyric acid anhydride (HFBA) at 70 degrees C for 30 min, and the derivatives were analyzed by electron ionization (EI) GC/MS in selected ion monitoring mode. Confirmation was accomplished by comparing retention times and the relative abundances of selected ions with those of standards. Deuterated analogs of the analytes were used as internal standards for quantification. Calibration curves for ten analytes were established in the concentration range 0.1-10 ng/mg with high correlation coefficients (r2 > 0.999). The intra-day and inter-day precisions were within 12.1% and 15.8%, respectively. The intra-day and inter-day accuracies were between -8.7% and 10.7%, and between -5.9% and 13.8%, respectively. The limit of detection (LOD) and limit of quantification (LOQ) obtained were 0.03 and 0.05 ng/mg for AP, MA, MDA, MDMA and MDEA; 0.05 and 0.08 ng/mg for K, NK, MOR and COD; and 0.08 and 0.1 ng/mg for 6-AM. The recoveries were above 88.6% for all the compounds, except K and NK which were in the range of 71.7-72.7%. Eight hair samples from known polydrug abusers were examined by this method. These results show that the method is suitable for broad-spectrum drug testing in a single hair specimen.