Journal of analytical toxicology (J ANAL TOXICOL )

Description

Journal of Analytical Toxicology (JAT) is the international source for practical clinical/forensic applications for isolating, identifying and quantitating potentially toxic substances. The Journal of Analytical Toxicology (JAT) is an international publication devoted to the timely dissemination of scientific communications concerning the isolation, identification, and quantitation of drugs and other substances. Since its inception in 1977, JAT has striven to present state-of-the art techniques to address current issues in toxicology. The peer-review process provided by the distinguished members of the Editorial Advisory Board ensures the high quality and integrity of JAT articles. Timely presentation of the latest scientific developments is ensured through "Technical Notes", "Case Reports", and "Letters to the Editor". Worldwide readership of JAT includes toxicologists, pathologists, chemists, clinicians, researchers, and educators working in medical examiner and law enforcement laboratories, hospitals, university, and independent analytical laboratories, as well as the drug manufacturing industry. With an emphasis on practical application, JAT articles introduce improved and novel techniques for use in clinical, forensic, workplace, sports testing (doping), and other toxicology laboratories. Articles describe newly developed methods in immunoassay testing, gas chromatography, liquid chromatography, mass spectrometry, atomic absorption spectrometry, solid- and liquid-phase extraction techniques, and other analytical approaches. The methods published in JAT describe the chemical analysis of therapeutic drugs, drugs of abuse, pharmaceuticals, pesticides, industrial chemicals, and environmental toxins. The methods are generally applicable to the fields of forensic science, therapeutic drug monitoring, drug abuse testing, clinical and forensic toxicology, industrial hygiene.

  • Impact factor
    2.11
  • 5-year impact
    1.76
  • Cited half-life
    8.60
  • Immediacy index
    0.43
  • Eigenfactor
    0.00
  • Article influence
    0.47
  • Website
    Journal of Analytical Toxicology (JAT) website
  • Other titles
    Journal of analytical toxicology, JAT
  • ISSN
    1945-2403
  • OCLC
    2942106
  • Material type
    Periodical
  • Document type
    Journal / Magazine / Newspaper

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: Driving under the influence (DUI) and DUI drugs (DUID) law enforcement (LE) cases (n = 12,082) where whole blood samples were submitted to ChemaTox Laboratory, Inc. in Boulder, CO, for testing were examined. Of these 12,082 cases, there were 4,235 cannabinoid screens (CS) requested. Samples that yielded a positive CS (n = 2,621) were further analyzed. A total of 1,848 samples were confirmed for Δ9-tetrahydrocannabinol (THC) after a positive CS. Due to a decrease in the confirmation limit of detection (LOD) for THC from 2 to 1 ng/mL, samples that were confirmed for THC and quantitated below 2 ng/mL (n = 250) were considered negative. After this normalization, there were 1,598 samples that were confirmed positive for THC and included in the analysis. The percentage of LE cases with requests for CS for all years was 35%, increasing from 28% in 2011 to 37% in 2013. The positivity rate of CS overall was 62% (range: 59-68% by year) with no significant change over the time frame examined. The percentage of positive CS in which THC was confirmed positive at or above 2 ng/mL (n = 1,598) increased significantly from 28% in 2011 to 65% in 2013. The mean and median THC concentrations were 8.1 and 6.3 ng/mL, respectively (range: 2-192 ng/mL, n = 1,367). The data presented illustrate a statistically significant increase in CS that result in positive THC confirmations. Although the specific cause of this increase is not known at this time, possible ties to ongoing developments in Colorado's marijuana legislation merit further analysis.
    Journal of analytical toxicology 10/2014; 38(8):575-81.
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    ABSTRACT: Only trace amounts of parent benzodiazepines are present in urine following extensive metabolism and conjugation. Thus, hydrolysis of glucuronides is necessary for improved detection. Enzyme hydrolysis is preferred to retain identification specificity, but can be costly and time-consuming. The assessment of a novel recombinant β-glucuronidase for rapid hydrolysis in benzodiazepine urinalysis is presented. Glucuronide controls for oxazepam, lorazepam and temazepam were treated with IMCSzyme™ recombinant β-glucuronidase. Hydrolysis efficiency was assessed at 55°C and at room temperature (RT) using the recommended optimum pH. Hydrolysis efficiency for four other benzodiazepines was evaluated solely with positive patient samples. Maximum hydrolysis of glucuronide controls at 5 min at RT (mean analyte recovery ≥94% for oxazepam and lorazepam and ≥80% for temazepam) was observed. This was considerably faster than the optimized 30 min incubation time for the abalone β-glucuronidase at 65°C. Mean analyte recovery increased at longer incubation times at 55°C for temazepam only. Total analyte in patient samples compared well to targets from abalone hydrolysis after recombinant β-glucuronidase hydrolysis at RT with no incubation. Some matrix effect, differential reactivity, conjugation variability and transformation impacting total analyte recovery were indicated. The unique potential of the IMCSzyme™ recombinant β-glucuronidase was demonstrated with fast benzodiazepine hydrolysis at RT leading to decreased processing time without the need for heat activation.
    Journal of analytical toxicology 10/2014; 38(8):610-4.
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    ABSTRACT: In December 2012, the possession and private use of limited quantities of marijuana and marijuana products became legal in the state of Washington. At the same time, the state's driving under the influence statutes were amended to include a per se level of 5 ng/mL delta(9)-tetrahydrocannabinol (THC) in whole blood for drivers aged 21 years and older. The aim of this study was to assess the effect of marijuana legalization on the prevalence of marijuana in suspected impaired driving cases. The prevalence of both active THC and its metabolite carboxy-THC detected in such cases pre-legalization was compared with the prevalence post-legalization. In 2009-2012, the average yearly percentage of cases positive for THC and carboxy-THC was 19.1% (range: 18.2-20.2%) and 27.9% (range: 26.3-28.6%), respectively. In 2013, the percentages had significantly increased to 24.9 and 40.0%, respectively (P < 0.05). The median THC concentration over the 5-year period ranged from 5.2 to 6.3 ng/mL, with individual concentrations ranging up to 90 ng/mL. An average of 56% of cases were at or >5 ng/mL over the 5-year period. The prevalence of alcohol and the majority of other drugs in this same population of suspected impaired drivers submitted for testing did not change during this same 5-year period-marijuana was the only drug to show such an increase in frequency. Further, this observed increase remained after the data had been normalized to account for changes in laboratory testing procedures that occurred during this time period. Future studies need be conducted to ascertain whether the observed increase has had any effect on the incidence of crashes, serious injuries and/or traffic fatalities.
    Journal of analytical toxicology 10/2014; 38(8):569-74.
  • Journal of analytical toxicology 10/2014; 38(8):465.
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    ABSTRACT: The Montgomery County Coroner's Office Toxicology Section and the Miami Valley Regional Crime Lab (MVRCL) Drug Chemistry Section have been receiving case work in drug seizures, death cases and human performance cases involving products marketed as heroin or as illicit fentanyl. Upon analysis by the Drug Chemistry Section, these products were found to contain various drug(s) including illicit fentanyl only, illicit fentanyl and heroin, illicit fentanyl and cocaine and illicit fentanyl, heroin and cocaine. Both the Chemistry and Toxicology Sections began seeing these combinations starting in late October 2013. The percentage of the combinations encountered by the MVRCL as well as the physical appearance of the product, and the results of presumptive screening tests will be discussed. The demographics of the users and the results of toxicology and autopsy findings on the decedents will also be discussed. According to regional drug task force undercover agents, there is evidence that some of the products are being sold as illicit fentanyl and not just as a heroin product. Also, there is no evidence to support that the fentanyl source is being diverted from pharmaceutical grade fentanyl. The chemistry section currently has over 109 confirmed cases, and the toxicology section currently has 81 confirmed drug deaths, 8 driving under the influence of drugs and 1 suicidal hanging. Both sections are continuing to see these cases at the present time.
    Journal of analytical toxicology 10/2014; 38(8):592-8.
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    ABSTRACT: This is the first reported case of α-pyrrolidinovalerophenone (α-PVP), methylone and ethylone in a suspected impaired driving case in the state of Washington. An initial traffic stop by law enforcement was made of a driver due to poor navigation of the roadway. The drug recognition expert (DRE) officer observed slurred speech, bloodshot watery eyes, dilated pupils, involuntary muscle movements and an elevated pulse and blood pressure. The DRE deduced that the driver was likely under the influence of central nervous system (CNS) stimulants, specifically 'bath salts'. Routine testing of the blood did not reveal the presence of alcohol or common drugs of abuse. Upon further review of the officer's report and the unconfirmed identification of α-PVP, blood was sent to NMS Labs in Willow Grove, PA, USA for bath salts and stimulant designer drugs testing. Analysis was conducted by liquid chromatography-time-of-flight mass spectrometry with the following results: 63 ng/mL α-PVP, 6.1 ng/mL methylone and positive for ethylone. These results are consistent with the DRE opinion of driving performance being impaired by a CNS stimulant.
    Journal of analytical toxicology 10/2014; 38(8):615-7.
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    ABSTRACT: Designer drugs appear to be increasing in popularity because of the ease of obtaining these constituents, the lack of ability to identify the substance(s) in routine drug screening, the appeal of the drug(s) being 'safe' due to them being marketed as a 'legal high' and possibly due to stronger restrictions that are being placed on prescription drugs. As components of designer drugs are identified and regulated by the DEA, new constituents, or analogs, of these designer drugs are being manufactured to circumvent legislation. 2,5-Dimethoxy-4-chloroamphetamine (DOC) is a substituted alpha-methylated phenethylamine and acts as a selective serotonin receptor partial agonist. There is limited literature on this particular compound and no literature that attributes death to use of this drug alone. We present a case of a 37-year-old male found at home lying face down next to a book titled 'Psychedelic Chemistry' by Michael Valentine Smith and in the early stages of decomposition. The decedent was a known methamphetamine abuser. A peripheral blood sample collected at autopsy was sent to toxicology for routine analysis. Results yielded negative for the drugs of abuse classes on the enzyme-linked immunosorbent assay screen but was positive for DOC during routine GC-MS analysis. A urine sample collected at autopsy was subjected to a routine urine liquid/liquid analysis via GC-MS, and the specimen was positive for DOC. Quantification analyses showed DOC concentration levels to be 377 ng/mL in iliac blood; 3,193 ng/mL in urine; 3,143 ng/g in liver and 683 ng/g in brain. DOC was not detected in the gastric contents. Caffeine was the only other compound detected in blood and urine. Due to the lack of literature, we believe that this is the first case where death can be attributed to DOC alone.
    Journal of analytical toxicology 10/2014; 38(8):589-91.
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    ABSTRACT: Methadone is difficult to administer as a therapeutic agent because of a wide range of interindividual pharmacokinetics, likely due to genetic variability of the CYP450 enzymes responsible for metabolism to its principal metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP). CYP3A4 is one of the primary CYP450 isoforms responsible for the metabolism of methadone to EDDP in humans. The purpose of this study was to evaluate the role of CYP3A4 genetic polymorphisms in accidental methadone fatalities. A study cohort consisting of 136 methadone-only and 92 combined methadone/benzodiazepine fatalities was selected from cases investigated at the West Virginia and Kentucky Offices of the Chief Medical Examiner. Seven single nucleotide polymorphisms (SNPs) were genotyped within the CYP3A4 gene. Observed allelic and genotypic frequencies were compared with expected frequencies obtained from The National Center for Biotechnology Information dbSNP database. SNPs rs2242480 and rs2740574 demonstrated an apparent enrichment within the methadone-only overdose fatalities compared with the control group and the general population. This enrichment was not apparent in the methadone/benzodiazepine cases for these two SNPs. Our findings indicate that there may be two or more SNPs on the CYP3A4 gene that cause or contribute to the methadone poor metabolizer phenotype.
    Journal of analytical toxicology 10/2014; 38(8):541-7.
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    ABSTRACT: The case reports for 18 driving cases positive for the synthetic cannabinoid substances XLR-11 and/or UR-144 are discussed. Eleven of these cases had drug recognition expert evaluations performed. Slurred speech, lack of convergence and body and eyelid tremors were the most consistently noted interview characteristic. Pulse and blood pressure of the subjects were within the expected range. Most of the drivers contacted demonstrated poor driving; however, their performance on the standardized field sobriety tests yielded inconsistent diagnostic information. All cases were negative for other commonly detected drugs that affect the central nervous system, although one case was additionally positive for other synthetic cannabinoids. Of the studied cases, six were positive for only UR-144, whereas eight contained only XLR-11. Four cases were found to have both.
    Journal of analytical toxicology 10/2014; 38(8):563-8.
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    ABSTRACT: As potent serotonin (5-HT2A) receptor agonists, the NBOMe class of drugs including 25B-, 25C-, 25D-, 25H-, 25I- and 25T2-NBOMe is frequently abused due to the intense hallucinations that they induce. From the limited literature available, the concentration of these NBOMe compounds reported in postmortem cases is exceedingly low. In most instances, published concentrations are <0.50 ng/mL. Therefore, the need for a sensitive, rapid and comprehensive analytical method for the quantification of these compounds was evident. In addition to the more publicized analog 25I-NBOMe, evaluation of 25B-, 25C-, 25D-, 25H and 25T2- in whole blood, plasma and urine was conducted. This publication presents the data obtained from the validation of a liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of these six NBOMe analogs. The method utilizes ultra-performance liquid chromatography technology for the separation followed by positive electrospray ionization of each analog. Limits of quantification for these analogs ranged from 0.01 to 0.02 ng/mL (10-20 pg/mL) with typical linear dynamic ranges of 0.01-20 ng/mL. Data for recovery, intraday control accuracy and precision, matrix effects, ion suppression/enhancement and analyte stability are included. Validation was completed in whole blood, plasma and urine. Short run times and high sensitivity afforded by this newly validated analytical method that allows for the detection of these six analogs in the most common toxicological matrices and can be applied to both ante- and postmortem specimens.
    Journal of analytical toxicology 10/2014; 38(8):479-84.
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    ABSTRACT: Many forensic laboratories experience backlogs due to increased drug-related cases. Laser diode thermal desorption (LDTD) has demonstrated its applicability in other scientific areas by providing data comparable with instrumentation, such as liquid chromatography-tandem mass spectrometry, in less time. LDTD-MS-MS was used to validate 48 compounds in drug-free human urine and blood for screening or quantitative analysis. Carryover, interference, limit of detection, limit of quantitation, matrix effect, linearity, precision and accuracy and stability were evaluated. Quantitative analysis indicated that LDTD-MS-MS produced precise and accurate results with the average overall within-run precision in urine and blood represented by a %CV <14.0 and <7.0, respectively. The accuracy for all drugs in urine ranged from 88.9 to 104.5% and 91.9 to 107.1% in blood. Overall, LDTD has the potential for use in forensic toxicology but before it can be successfully implemented that there are some challenges that must be addressed. Although the advantages of the LDTD system include minimal maintenance and rapid analysis (∼10 s per sample) which makes it ideal for high-throughput forensic laboratories, a major disadvantage is its inability or difficulty analyzing isomers and isobars due to the lack of chromatography without the use of high-resolution MS; therefore, it would be best implemented as a screening technique.
    Journal of analytical toxicology 10/2014; 38(8):528-35.
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    ABSTRACT: High-resolution mass spectrometry (HRMS) is being applied in postmortem drug screening as an alternative to nominal mass spectrometry, and additional evaluation in quantitative casework is needed. We report quantitative analysis of benzoylecgonine, citalopram, cocaethylene, cocaine, codeine, dextromethorphan, dihydrocodeine, diphenhydramine, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, hydrocodone, hydromorphone, meperidine, methadone, morphine, oxycodone and oxymorphone in postmortem blood by ultra-performance liquid chromatography (UPLC)-MS(E)/time-of-flight (TOF). The method employs analyte-matched deuterated internal standardization and MS(E) acquisition of precursor and product ions at low (6 eV) and ramped (10-40 eV) collision energies, respectively. Quantification was performed using precursor ion data obtained with a mass extraction window of ±5 ppm. Fragment and residual precursor ion acquisitions at ramped collision energies were evaluated as additional analyte identifiers. Extraction recovery of >60% and matrix effect of <20% were determined for all analytes and internal standards. Defined limits of detection (10 ng/mL) and quantification (25 ng/mL) were validated along with a linearity analytical range of 25-3,000 ng/mL (R(2) > 0.99) for all analytes. Parallel UPLC-MS(E)/TOF and UPLC-MS/MS analysis showed comparable precision and bias along with concordance of 253 positive (y = 1.002x + 1.523; R(2) = 0.993) and 2,269 negative analyte findings in 159 postmortem cases. Analytical performance and correlation studies demonstrate accurate quantification by UPLC-MS(E)/TOF and extended application of HRMS in postmortem casework.
    Journal of analytical toxicology 10/2014; 38(8):495-506.
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    ABSTRACT: An evaluation of an internal laboratory decision to implement a protocol for limiting drug testing based on ethanol concentration in laboratory analysis for driving under the influence (DUI) cases is presented. The described case management strategy is supported by known impairment of ethanol at relatively high concentrations, difficulty assigning a level of contributing impairment from drugs in the presence of high ethanol levels and the likelihood that the drug results may be suppressed at trial. Although the results of this study reinforce the assertion that such protocols lead to the under reporting of drugs in DUI cases, for the majority of cases, 95% in this study, the drug analysis results were not significant and did not warrant the time and resources needed for the additional blood drug testing. Furthermore, the study demonstrated that a high drug positivity rate does not necessarily mean that those drug results are legally or pharmacologically meaningful. Additional research should be conducted with quantitative drug results and casework impact of blood drug screen protocols as previous studies only report drug positivity rates and not whether the drug results would be meaningful to the case.
    Journal of analytical toxicology 10/2014; 38(8):555-8.
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    ABSTRACT: An automated assay was modified and validated to qualitatively screen for 6-acetylmorphine (6-AM) in oral fluid using the Siemens EMIT II(®) Plus 6-AM urine assay. The validation utilized an oral fluid calibrator at the currently proposed Substance Abuse and Mental Health Services Administration cutoff concentration of 4 ng/mL, as well as quality control material prepared and validated through liquid chromatography-tandem mass spectrometry. All calibrator, quality control and unknown specimens were analyzed based on the dilution and buffering system of the Quantisal(®) oral fluid collection device. Immunoassay parameters such as the pipetted sample and reagent volumes as well as photometric read times were adjusted as part of the assay modification process. Validation experiments included the determination of intra- and inter-day precision and reproducibility, limits of detection (LODs), assay selectivity, stability studies and a specimen agreement study (n = 132). The 6-AM assay performed well in all validation experiments, over multiple days and under various laboratory conditions. The LOD was determined to be 1.844 ng/mL. The assay sensitivity, specificity and overall misclassification rate were found to be 90, 100 and 6%, respectively.
    Journal of analytical toxicology 10/2014; 38(8):605-9.
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    ABSTRACT: Zolpidem is a nonbenzodiazepine sedative hypnotic drug used for the short-term treatment of insomnia. While quite effective in producing sedation, zolpidem has potentially hazardous side effects when put in the context of complex tasks. Therefore, to more fully understand the postmortem concentrations of zolpidem, our laboratory has developed a sensitive method for the quantitation of zolpidem in biological specimens. Additionally, we have evaluated the distribution of zolpidem in various postmortem tissues and fluids from 10 aviation fatalities. This method incorporated a modified acetonitrile 'crash and shoot' extraction and a Waters Xevo TQ-S with an Acquity ultra-performance liquid chromatograph. The linear dynamic range was 0.4-800 ng/mL. The extraction efficiencies ranged from 78 to 87%, depending on the concentration. Postmortem blood zolpidem concentrations in these 10 cases ranged from 7.6 to 76.5 ng/mL. The highest concentrations of zolpidem present in each victim were found in the liver, spleen, lung and kidney tissues. Distribution coefficients for zolpidem were determined for each of the specimen types analyzed. These coefficients are expressed relative to the blood concentration in each case. This method proved to be simple, accurate and robust for the identification and quantitation of zolpidem in postmortem fluids and tissues.
    Journal of analytical toxicology 10/2014; 38(8):507-12.
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    ABSTRACT: During prolonged strenuous exercise, racehorses can experience acidemia. To counteract this phenomenon, trainers can administer blood alkalizing agents that raise the plasma pH and total carbon dioxide (TCO2) concentration. In Illinois, the administrative threshold for TCO2 in plasma is 37.0 mmol/L. Because accuracy in the reported measurement of TCO2 must be ensured, uncertainty measurements are often issued alongside the reported concentrations. We report a validated method for measuring TCO2 levels in equine plasma using the Beckman UniCel DxC 600. A six-point calibration curve ranging from 5 to 50 mmol/L is analyzed along with controls at four TCO2 levels with each set of samples. Using this method, we collected data from 5,199 race samples during 2012, with 134 being from thoroughbred horses and 5,065 from standardbred horses. During method validation, uncertainty was determined using the simplified Guide to the Expression of Uncertainty in Measurement approach and was found to be 3% at 99.7% confidence level with eight measurements. Additionally, to investigate other variables that could have an effect on TCO2 levels, we collected the gender, breed, Lasix(®) status, strong ion concentration, pre- or post-race collection time and track location of all horses tested during that year. The samples had an overall mean TCO2 concentration of 30.5 ± 2.0 mmol/L. The other physiological and environmental data were analyzed using analysis of covariance tables. These results indicate gender, breed, furosemide status, collection time and track location to be strongly correlated (P < 0.0001) to TCO2 levels. Thoroughbred status was found to have no effect. Finally, TCO2 concentrations were highly correlated (P < 0.0001) to sodium and chloride ion concentrations. No correlation was found between TCO2 and potassium concentrations. The results show that there are several environmental and physiological factors that can affect TCO2 concentrations. The concentration of other strong ions present in the blood may indicate doping status.
    Journal of analytical toxicology 10/2014; 38(8):536-40.
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    ABSTRACT: AH-7921 (3,4-dichloro-N-[(1-dimethylamino)cyclohexylmethyl]benzamide) is a designer opioid with ∼80% of morphine's µ-agonist activity. Over a 6-month period, we encountered nine deaths where AH-7921 was involved and detected in blood from the deceased. Shortly after the last death, on August 1 2013, AH-7921 was scheduled as a narcotic and largely disappeared from the illicit market in Sweden. AH-7921 was measured by a selective liquid chromatography-MS-MS method and the concentrations of AH-7921 ranged from 0.03 to 0.99 µg/g blood. Six of our cases had other drugs of abuse on board and most had other medications such as benzodiazepines, antidepressants and analgesics. However, the other medicinal drugs encountered were present in postmortem therapeutic concentrations and unlikely to have contributed to death. In addition to the parent compound, we identified six possible metabolites where two N-demethylated dominated and four mono-hydroxylated were found in trace amounts in the blood. In conclusion, deaths with AH-7921 seem to occur both at low and high concentrations, probably a result of different tolerance to the drug. Hence, it is reasonable to assume that no sharp dividing line exists between lethal and non-lethal concentrations. Further, poly-drug use did not seem to be a major contributing factor for the fatal outcome.
    Journal of analytical toxicology 10/2014; 38(8):599-604.
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    ABSTRACT: In recent years, there has been a growth in reports of antiepileptic drugs (AEDs) being misused on their own or in combination with other drugs of abuse in a variety of toxicological case types such as drug abuse, suicide, overdose and drug facilitated crime. To our knowledge, there are no simultaneous quantification methods for the analysis of the most commonly encountered AEDs in postmortem whole blood and clinical plasma/serum samples at the same time. A simple, accurate and cost-effective liquid chromatography-tandem mass spectrometric (LC-MS-MS) method has been developed and validated for the simultaneous quantification of carbamazepine (CBZ) and its metabolite CBZ-10,11-epoxide, eslicarbazepine acetate, oxcarbazepine and S-licarbazepine as a metabolite, gabapentin, lacosamide, lamotrigine, levetiracetam, pregabalin, phenobarbital, phenytoin and its metabolite 5-(p-hydroxyphenyl)-5-phenylhydantoin, retigabine (ezogabine) and its metabolite N-acetyl retigabine, rufinamide, stiripentol, topiramate, tiagabine, valproic acid, vigabatrin and zonisamide in postmortem whole blood, serum and plasma which would be suitable for routine forensic toxicological analysis and therapeutic drug monitoring. All AEDs were detected and quantified within 17 min without endogenous interferences. The correlation coefficient (R(2)) was >0.995 for all AEDs with accuracy ranging from 90 to 113% and precision <13% for all analytes. The recovery ranged from 70 to 98%. No carryover was observed in a blank control injected after the highest standard and the matrix effect was acceptable and ranged from 90 to 120%. The method has been successfully verified using authentic case samples that had previously been quantified using different methods.
    Journal of analytical toxicology 10/2014; 38(8):485-94.
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    ABSTRACT: Synthetic cannabinoids represent an emerging drug problem in the USA, as these compounds are constantly being modified and rapidly sold as soon as they become available. Laboratories around the world are constantly improving the analytical methods to detect and identify these newly available designer drugs. This study used a simple approach to detect and quantify a variety of synthetic cannabinoids (14 parent compounds and 15 metabolites including series XLR, AM, JWH, UR, RCS, PB, HU and AB-FUBINACA) using LC-MS-MS. Drug-free urine samples spiked with various synthetic cannabinoids and their metabolites were separated on a C18-Hypersil Gold column using an Agilent 1290 ultra-high performance liquid chromatography and detected by an AB Sciex API 4000 tandem mass spectrometer. Studies were carried out to determine limit of detection, limit of quantitation, upper limit of linearity, ion suppression, interference, precision and accuracy to validate the method. Urine samples from patients and known users were hydrolyzed with β-glucuronidase prior to the analysis by LC-MS-MS, and the data are presented. The method described here is rapid, highly sensitive and specific for the identification of a variety of synthetic cannabinoids.
    Journal of analytical toxicology 10/2014; 38(8):466-78.
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    ABSTRACT: Zolpidem (Ambien(®)) is the most prescribed insomnia treatment in the USA; however, little is known about zolpidem metabolite excretion in chronic pain patients. As zolpidem is extensively metabolized in vivo to zolpidem 4-phenyl carboxylic acid (ZCA), metabolite detection may provide improved accuracy for compliance determinations, thereby improving clinical decisions. Zolpidem and ZCA were extracted from 1 mL human urine by mixed-mode solid-phase extraction. Samples were analyzed by LC-MS-MS using positive electrospray ionization with multiple reaction monitoring mode employed for detection and quantification. Gradient chromatographic separation was achieved with a reversed-phase column in a rapid 1.8 min analysis. The assay was linear from 4 to 1,000 µg/L for zolpidem and 4 to 10,000 µg/L for ZCA. Interday recovery (bias) and imprecision (n = 20) were 100-107% of target and 2.4-3.7% relative standard deviation, respectively. Extraction efficiencies were 78-90%. Pain compliance samples (n = 3,142) were de-identified and analyzed for zolpidem and ZCA. Zolpidem was detected greater than limit of quantification in 720 specimens (22.9%), while ZCA was detected in 1,579 specimens (50.3%). Only five specimens contained zolpidem alone. ZCA was observed without parent zolpidem in 864 specimens, thereby increasing population detection rates by 27.5%. Addition of a zolpidem metabolite to compliance determinations substantially improved detection for zolpidem intake and also should prove useful in clinical and forensic settings.
    Journal of analytical toxicology 10/2014; 38(8):513-8.

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