Journal of analytical toxicology (J ANAL TOXICOL)

Publisher: Oxford University Press (OUP)

Journal 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.

Current impact factor: 2.63

Impact Factor Rankings

2015 Impact Factor Available summer 2015
2013 / 2014 Impact Factor 2.627
2012 Impact Factor 2.107
2011 Impact Factor 2.022
2010 Impact Factor 1.545
2009 Impact Factor 1.867
2008 Impact Factor 1.665
2007 Impact Factor 2.068
2006 Impact Factor 1.242
2005 Impact Factor 1.785
2004 Impact Factor 1.722
2003 Impact Factor 1.782
2002 Impact Factor 1.256
2001 Impact Factor 1.417
2000 Impact Factor 1.592
1999 Impact Factor 2.221
1998 Impact Factor 1.834
1997 Impact Factor 2.168

Impact factor over time

Impact factor

Additional details

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

Publisher details

Oxford University Press (OUP)

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Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: The Substance Abuse and Mental Health Services Administration (SAMHSA) is currently evaluating hydrocodone (HC) for inclusion in the Mandatory Guidelines for Federal Workplace Drug Testing Programs. This study evaluated the time course of HC, norhydrocodone (NHC), dihydrocodeine (DHC) and hydromorphone (HM) in paired oral fluid and whole blood specimens by liquid chromatography-tandem mass spectrometry (limit of quantitation = 1 ng/mL of oral fluid, 5 ng/mL of blood) over a 52-h period. A single dose of HC bitartrate, 20 mg, was administered to 12 subjects. Analyte prevalence was as follows: oral fluid, HC > NHC > DHC; and blood, HC > NHC. HM was not detected in any specimen. HC was frequently detected within 15 min in oral fluid and 30 min in blood. Mean oral fluid to blood (OF : BL) ratios and correlations were 3.2 for HC (r = 0.73) and 0.7 for NHC (r = 0.42). The period of detection for oral fluid exceeded blood at all evaluated thresholds. At a 1-ng/mL threshold for oral fluid, mean detection time was 30 h for HC and 18 h for NHC and DHC. This description of HC and metabolite disposition in oral fluid following single-dose administration provides valuable interpretive guidance of HC test results. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 05/2015; DOI:10.1093/jat/bkv050
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    ABSTRACT: A highly sensitive and fully validated method was developed for the quantification of buprenorphine in postmortem blood. After a two-step protein precipitation process using acetonitrile, buprenorphine was purified using mixed-mode (C8/cation exchange) solid-phase extraction cartridges. Endogenous water-soluble compounds and lipids were removed from the cartridges before the samples were eluted, concentrated and derivatized using N-methyl-N-trimethylsilyltrifluoroacetamide. The samples were analyzed using two-dimensional gas chromatography-mass spectrometry (2D GC-MS) in selective ion-monitoring mode. A low polarity Rxi(®)-5MS (30 m × 0.25 mm I.D. × 0.25 µm) was used as the primary column and the secondary column was a mid-polarity Rxi(®) -17Sil MS (15 m × 0.32 mm I.D. × 0.25 µm). The assay was linear from 1.0 to 50.0 ng/mL (r(2) > 0.99; n = 6). Intraday (n = 6) and interday (n = 9) imprecisions (percentage relative standard deviation, % RSD) were <5% and the average recovery was 60%. The limit of detection (LOD) of the method was 0.5 ng/mL and limit of quantification was 1.0 ng/mL. 2D GC-MS improved the LOD of buprenorphine by 20-fold compared with analysis on a conventional GC-MS. The method was highly selective with no interference from endogenous compounds or from 62 commonly encountered drugs. To prove method applicability to forensic postmortem cases, 14 authentic postmortem blood samples were analyzed. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 05/2015; DOI:10.1093/jat/bkv051
  • Journal of analytical toxicology 05/2015; DOI:10.1093/jat/bkv033
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    ABSTRACT: The occurrence of structurally related synthetic cannabinoids makes the identification of unique markers of drug intake particularly challenging. The aim of this study was to identify unique and abundant metabolites of AKB-48 and 5F-AKB-48 for toxicological screening in urine. Investigations of authentic urine samples from forensic cases in combination with human liver microsome (HLM) experiments were used for identification of metabolites. HLM incubations of AKB-48 and 5F-AKB-48 along with 35 urine samples from authentic cases were analyzed with liquid chromatography quadrupole tandem time of flight mass spectrometry. Using HLMs 41 metabolites of AKB-48 and 37 metabolites of 5F-AKB-48 were identified, principally represented by hydroxylation but also ketone formation and dealkylation. Monohydroxylated metabolites were replaced by di- and trihydroxylated metabolites within 30 min. The metabolites from the HLM incubations accounted for on average 84% (range, 67-100) and 91% (range, 71-100) of the combined area in the case samples for AKB-48 and 5F-AKB-48, respectively. While defluorinated metabolites accounted for on average 74% of the combined area after a 5F-AKB-48 intake only a few identified metabolites were shared between AKB-48 and 5F-AKB-48, illustrating the need for a systematic approach to identify unique metabolites. HLMs in combination with case samples seem suitable for this purpose. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 05/2015; DOI:10.1093/jat/bkv045
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    ABSTRACT: A rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS-MS) method was developed, validated and applied to simultaneous analysis of oral fluid samples for the following 10 analytes: methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), buprenorphine, norbuprenorphine, morphine, codeine, 6-acetylmorphine, 6-acetylcodeine, amphetamine, and methamphetamine. The oral fluid sample was briefly centrifuged and the supernatant was directly injected into the LC-MS-MS system operated under reverse-phase chromatography and electrospray ionization (ESI). Deuterated analogs of the analytes were adopted as the internal standards and found to be effective (except for buprenorphine) to compensate for potential matrix effects. Each analytical run took <10 min. Linearity range (r(2) > 0.99) established for buprenorphine and the other nine analytes were 5-100 and 1-100 ng/mL. Intra- and interday precision (% CV) ranges for the 10 analytes were 0.87-12.2% and 1.27-12.8%, while the corresponding accuracy (%) ranges were 91.8-113% and 91.9-111%. Limits of detection and quantitation established for these 10 analytes were in the ranges of 0.1-1.0 and 0.25-1.0 ng/mL (5 ng/mL for buprenorphine). The method was successfully applied to the analysis of 62 oral fluid specimens collected from patients participating in methadone and buprenorphine substitution therapy programs. Analytical results of methadone and buprenorphine were compared with data derived from GC-MS analysis and found to be compatible. Overall, the direct injection LC-MS-MS method performed well, permitting rapid analysis of oral fluid samples for simultaneous quantification of methadone, buprenorphine, opiate and amphetamine drug categories without extensive sample preparation steps. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 05/2015; DOI:10.1093/jat/bkv041
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    ABSTRACT: In this case report, we present an evaluation of the distribution of postmortem concentrations of acetyl fentanyl in a fatality attributed to the drug. A young man who had a history of heroin abuse was found deceased at his parents' home. Toxicology testing, which initially screened positive for fentanyl by ELISA, subsequently confirmed acetyl fentanyl by gas chromatography-mass spectrometry specific ion monitoring (GC-MS SIM) analysis following liquid-liquid extraction. No other drugs or medications, including fentanyl, were detected. The acetyl fentanyl peripheral blood concentration was quantified at 260 ng/mL compared with the central blood concentration of 250 ng/mL. The liver concentration was 1,000 ng/kg, the vitreous was 240 ng/mL and the urine was 2,600 ng/mL. The cause of death was certified due to acute acetyl fentanyl intoxication, and the manner of death was certified as an accident. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv043
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    ABSTRACT: This study was conducted to investigate the deposition and depletion process of clenbuterol (CL) in goat tissues, plasma and urine after the repeated administration of a growth-promoting dose. The experiment was conducted in 24 goats (21 treated and 3 controls). Treated animals were administered orally in a dose of 16 µg/kg body mass once daily for 21 consecutive days and randomly sacrificed on days 0.25, 1, 3, 7, 14, 21 and 28 of the withdrawal period. CL in goat tissues was extracted with organic solvents and determined using liquid chromatography tandem mass spectrometry. The depletion rates of tissue differed significantly. The highest concentrations of CL in all tissues are detected on day 0.25 of treatment discontinuation. After administration had been discontinued for 28 days, CL still residues in all tissues, especially, in whole eye, where the concentrations reach 363.29 ± 31.60 μg/kg. These findings confirmed that the whole eye, which are rich in pigment, showed a much higher concentration than any other studied tissue during the withdrawal period. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv038
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    ABSTRACT: Xylazine as veterinary medicine for sedation, but intoxication cases in humans were identified in the last few years. A highly sensitive method is required for analyzing xylazine and its metabolites in human blood and urine. This article presents an ultra high performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UHPLC-QTOF) study for simultaneous determination of xylazine and 2,6-dimethylaniline (DMA) in human blood and urine. The samples were extracted and cleaned up by Oasis MCX solid-phase extraction. The analysis is performed using an UHPLC-QTOF. Analysis precision, accuracy, sensitivity, linear range, limit of detection (LOD) and limit of quantification (LOQ) were validated for the proposed method. In the blood and urine samples, the linear calibration curves with high linearity are obtained over the range of 2.0-1,000.0 ng/mL. The LOD for xylazine and DMA in blood are 0.2 and 0.1 ng/mL, in urine are 0.4 and 0.2 ng/mL; the LOQ for xylazine and DMA in blood are 0.6 and 0.3 ng/mL, in urine are 1.0 and 0.6 ng/mL, respectively. The intra- and interday precision is better than 8.6 and 11.9%. In conclusion, the proposed method is highly sensitive and reproducible, thus suitable for accurate quantification of xylazine and its metabolites in blood and urine. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv040
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    ABSTRACT: Ethylene glycol (EG) is used in antifreeze and other industrial products. It metabolizes to glycolic acid (GA) and oxalic acid (OX) that cause metabolic acidosis and are mainly responsible for the toxicity of EG. During 2010-2014, EG or GA was found in 25 postmortem cases in Finland. Of these cases, 21 were classified as fatal EG poisonings and 3 were classified as methanol (MeOH) poisonings. In this study, we report the concentrations of EG and GA in postmortem blood and urine samples of fatal EG or mixed MeOH/EG poisonings. In the fatal EG poisonings, the median EG and GA concentrations were 0.87 and 1.6 g/L in blood and 4.3 and 5.3 g/L in urine. The median urine-blood ratios were 3.8 and 3.1 for EG and GA. These results warrant the use of urine as a primary matrix for screening. In EG positive cases, the quantification of both EG and GA in blood is crucial as GA concentration appears to best indicate a fatal poisoning with an approximate threshold of 1.5 g/L. The measurement of urinary OX does not offer much additional value to toxic alcohol screening as it may originate from varying dietary conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv044
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    ABSTRACT: The effect of long-term room temperature storage on the stability of ethanol in whole blood specimens was investigated. One hundred and seventeen preserved whole blood case samples (110 of 117 with two tubes of blood in each case) were used for this study. One tube from each case was initially tested for blood alcohol concentration (BAC) for criminal driving under the influence proceedings. Cases positive for ethanol ranged in BAC from 0.023 to 0.281 g/dL. The second tube, if present, remained sealed. All blood samples were then stored at room temperature. After 5.4-10.3 years, the opened tubes were reanalyzed for BAC by the same laboratory that performed the initial testing using the same method and same instrumentation. After the same storage period, the unopened tubes were sent to a different laboratory, using a different method and different instrumentation, and reanalyzed for BAC after a total of 5.6-10.5 years of room temperature storage. Seven samples initially negative for alcohol remained negative. All samples initially positive for ethanol demonstrated a decrease in BAC over time with a statistically significant difference in loss observed based on blood sample volume and whether or not the tube had been previously opened. The decrease in BAC ranged from 0.005 to 0.234 g/dL. Tubes that were not previously opened and were more than half full demonstrated better BAC stability with 89% of these tubes demonstrating a loss of BAC between 0.01 and 0.05 g/dL. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv037
  • Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv034
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    ABSTRACT: Crack cocaine (free-base cocaine) smokers belong to a subgroup of marginalized drug users exposed to severe health risks and great social harm. Detection of the urinary, pyrolytic biomarker methylecgonidine (MED) and its metabolite ecgonidine (ED) secures an unambiguous confirmation of crack cocaine smoking. Although prevalence studies of cocaine based upon self-reporting may not be accurate, laboratory analysis is seldom used for neither diagnostic purpose nor early identification of crack cocaine smoking, which is far more severe than snorting cocaine. A new analytical method was validated for MED, ED and other relevant cocaine metabolites using automated liquid handling and column switching coupled to liquid chromatography and tandem mass spectrometry. Limit of quantification was 30 ng/mL for ED and MED. This method was applied in a laboratory study of urine samples (n = 110) from cocaine users in Denmark subjected to routine drugs-of-abuse testing. Crack cocaine smoking was confirmed by the presence of MED and/or ED. Eighty-four samples (76.4%) were found positive for crack cocaine smoking in this group of problematic cocaine users. MED was only detected in 5.9% of the positive samples. The study shows a prevalence 3-fold higher to that recently suggested by European Monitoring Centre for Drugs and Drug Addiction. We therefore advocate that the urinary biomarkers MED and ED are included in routine testing methods for clinical toxicology. This may lead to an earlier identification of crack cocaine smoking and possibly prevent a more severe drug use. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv035
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    ABSTRACT: In this article, optimization and validation of a procedure for the determination of total nickel in wet digested samples of human body tissues (internal organs) for forensic toxicological purposes are presented. Four experimental setups of the electrothermal atomic absorption spectrometry (ETAAS) using a Solaar MQZe (Thermo Electron Co.) were compared, using the following (i) no modifier, (ii) magnesium nitrate, (iii) palladium nitrate and (iv) magnesium nitrate and ammonium dihydrogen phosphate mixture as chemical modifiers. It was ascertained that the ETAAS without any modifier with 1,300/2,400°C as the pyrolysis and atomization temperatures, respectively, can be used to determine total nickel at reference levels in biological materials as well as its levels found in chronic or acute poisonings. The method developed was validated, obtaining a linear range of calibration from 0.76 to 15.0 μg/L, limit of detection at 0.23 µg/L, limit of quantification at 0.76 µg/L, precision (as relative standard deviation) up to 10% and accuracy of 97.1% for the analysis of certified material (SRM 1577c Bovine Liver) and within a range from 99.2 to 109.9% for the recovery of fortified liver samples. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv039
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    ABSTRACT: Opioid-related mortality rates have escalated. Drug interactions may increase blood concentrations of the opioid. We therefore used human liver microsomes (HLMs) and cDNA-expressed human cytochrome P450s (rCYPs) to study in vitro inhibition of buprenorphine metabolism to norbuprenorphine (CYP3A4 and 2C8), oxycodone metabolism to noroxycodone (CYP3A4 and 2C18) and oxymorphone (CYP2D6), and methadone metabolism to R- and S-2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP; CYP3A4 and 2B6). In this study, we have examined the inhibitory effect of 12 (mostly antifungal) azoles. These compounds have a wide range of solubility; to keep organic solvent ≤1%, there was an equally wide range of highest concentration tested (e.g., itraconazole 5 µM to fluconazole 1000 µM). Inhibitors were first incubated with HLMs at three concentrations with or without preincubation of inhibitor with reducing equivalents to also screen for time-dependent inhibition (TDI). Posaconazole displayed evidence of TDI; metronidazole and albendazole had no significant effect. Azoles were next screened at the highest achievable concentration for non-CYP3A4 pathways. IC50 values (µM) were determined for most CYP3A4 pathways (ranges) and other pathways as dictated by screen results: clotrimazole (0.30 - 0.35; others >30 µM); econazole (2.2 - 4.9; 2B6 R-EDDP - 9.5, S-EDDP - 6.8; 2C8 - 6.0; 2C18 - 1.0; 2D6 - 1.2); fluconazole (7.7 - 66; 2B6 - 313, 361; 2C8 - 1240; 2C18 - 17; 2D6 - 1000); itraconazole (2.5 to >5; others >5); ketoconazole (0.032 - 0.094; 2B6 - 12, 31; 2C8 - 78; 2C18 - 0.98; 2D6 - 182); miconazole (2.3 - 7.6; 2B6 - 2.8, 2.8; 2C8 - 5.3; 2C18 - 3.1; 2D6 - 5.9); posaconazole (3.4 - 20; 2C18 - 3.8; others >30); terconazole (0.48 to >10; 2C18 - 8.1; others >10) and voriconazole (0.40 - 15; 2B6 - 2.4, 2.5; 2C8 - 170; 2C18 - 13; 2D6 >300). Modeling based on estimated Ki values and plasma concentrations from the literature suggest that the orally administered azoles, particularly ketoconazole and voriconazole, have the greatest potential for inhibiting CYP3A4 pathways, as does voriconazole for the CYP2B6 pathways. Azoles used for mucosal and topical applications did not exceed the modeling threshold. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv030
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    ABSTRACT: Nefopam is a non-opiate analgesic commonly used for the treatment of moderate to severe pain. A case of a 37-year-old male who was found dead in the morning is presented. An autopsy was performed and femoral venous blood, heart blood, urine, and vitreous humor were submitted for toxicological analysis. A general drug screen detected the presence of nefopam, caffeine, nicotine, citalopram, gabapentin, amitriptyline, diazepam and paracetamol in cardiac blood. Nefopam was quantitated by high-performance liquid chromatography with diode-array detection. Nefopam was found at the following concentrations: 13.6 mg/L in unpreserved femoral blood; 14.7 mg/L in preserved (fluoride-oxalate) femoral blood; 21.2 mg/L in unpreserved cardiac blood and 4.5 mg/L in preserved vitreous. Citalopram was present at a concentration of 0.7 mg/L (femoral blood) and 0.9 mg/L (cardiac blood). Ethanol analyzed by headspace gas chromatography (GC-FID) was detected in preserved (fluoride-oxalate) vitreous (14 mg/100 mL) and preserved (fluoride-oxalate) urine 50 mg/100 mL. Death was attributed to atherosclerotic coronary artery disease and therapeutic drug toxicity. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv036
  • Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv032
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    ABSTRACT: The opioids codeine and morphine have legitimate uses in managing chronic pain conditions, but they are frequently abused. Patients prescribed opioids submit urine samples for medication compliance monitoring, and the interpretation of the results is complex. The purpose of this study was to evaluate the percentage of codeine- and morphine-positive urine drug tests that result from morphine use only, with the positive codeine result arising from low levels of codeine present in pharmaceutical formulations of morphine. This study included 80 urine samples which tested positive for codeine and morphine after pre-analytical hydrolysis and analysis by gas chromatography-mass spectrometry. Quantitative results were correlated with patient prescription information and immunoassay results to classify patients into one of four categories: heroin users (50%), codeine users (34%), codeine and morphine users (5%), and morphine users (11%). The percentage of codeine-positive resulting from morphine use was higher than previous estimates. Urine from patients prescribed morphine only was found to contain codeine at <1% of the morphine concentration, a ratio that was also observed in patients who used heroin. Careful analysis of urine drug testing results, including assessing the ratio of codeine to morphine (C/M), can help providers determine if patients are compliant with their pain management regimens. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv031
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    ABSTRACT: A novel LC-MS-MS assay that simultaneously detects and quantitates 78 drugs and metabolites was developed and validated for chronic pain management. Urine specimen was diluted and mixed with internal standards (ISs) before injected into LC-MS-MS. Seventy-two analytes were detected with positive electrospray ionization mode and the remaining six analytes with negative mode. Two separate gradient elution chromatographic programs were established with the same mobile phases on the same bi-phenyl HPLC column. The assay was linear for all analytes with linear regression coefficient ranging 0.994-1.000. The intra-assay precision was between 1.7 and 8.8% and inter-assay precision between 1.9 and 12.2%, with bias <20% for all but six analytes. All analytes in urine specimens were stable for 7 days at 4°C, and no significant matrix effect or carryover was observed. A suboptimal recovery rate (60.0-156.8%) was observed for six analytes, potentially due to the lack of available deuterated ISs, requiring comparison to a chemically different IS. Method comparison using patient and proficiency testing samples demonstrated that this assay was sensitive and accurate. The assay improves on currently existing assays by including glucuronide conjugates, allowing direct detection of metabolites that might otherwise be missed by existing methods. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 04/2015; DOI:10.1093/jat/bkv024
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    ABSTRACT: Uncertainty is an inherent property of all measurements. The magnitude of this uncertainty will determine the number of meaningful digits that should be reported in a measurement result. Several statistical arguments are considered providing evidence that three digit truncated results are more appropriate than two since the first significant digit of the combined uncertainty (standard deviation) in breath alcohol measurement is found in the third decimal place. Probably, the most compelling reason for reporting three digits is the significant reduction in combined uncertainty compared with the use of two digits. For a breath alcohol concentration of 0.089 g/210 L, the combined uncertainty for two digit results is ∼0.0042 g/210 L, compared with 0.0031 g/210 L for three digit results. The historical practice of reporting two digit truncated results in forensic breath alcohol analysis has been largely based on the use of analog scale instruments with 0.01 g/210 L scale resolution. With today's modern digital instrumentation, this practice should be reconsidered. While the focus of this paper is on breath alcohol analysis, the general principles will apply to any quantitative analytical measurement. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email:
    Journal of analytical toxicology 03/2015; DOI:10.1093/jat/bkv025