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Featured researches published by Matthew N. Newmeyer.


Forensic Science International | 2014

Morphine and codeine concentrations in human urine following controlled poppy seeds administration of known opiate content

Michael L. Smith; Daniel C. Nichols; Paula Underwood; Zachary Fuller; Matthew A. Moser; Charles LoDico; David A. Gorelick; Matthew N. Newmeyer; Marta Concheiro; Marilyn A. Huestis

Opiates are an important component for drug testing due to their high abuse potential. Proper urine opiate interpretation includes ruling out poppy seed ingestion; however, detailed elimination studies after controlled poppy seed administration with known morphine and codeine doses are not available. Therefore, we investigated urine opiate pharmacokinetics after controlled oral administration of uncooked poppy seeds with known morphine and codeine content. Participants were administered two 45 g oral poppy seed doses 8 h apart, each containing 15.7 mg morphine and 3mg codeine. Urine was collected ad libitum up to 32 h after the first dose. Specimens were analyzed with the Roche Opiates II immunoassay at 2000 and 300 μg/L cutoffs, and the ThermoFisher CEDIA(®) heroin metabolite (6-acetylmorphine, 6-AM) and Lin-Zhi 6-AM immunoassays with 10 μg/L cutoffs to determine if poppy seed ingestion could produce positive results in these heroin marker assays. In addition, all specimens were quantified for morphine and codeine by GC/MS. Participants (N=22) provided 391 urine specimens over 32 h following dosing; 26.6% and 83.4% were positive for morphine at 2000 and 300 μg/L GC/MS cutoffs, respectively. For the 19 subjects who completed the study, morphine concentrations ranged from <300 to 7522 μg/L with a median peak concentration of 5239 μg/L. The median first morphine-positive urine sample at 2000 μg/L cutoff concentration occurred at 6.6 h (1.2-12.1), with the last positive from 2.6 to 18 h after the second dose. No specimens were positive for codeine at a cutoff concentration of 2000 μg/L, but 20.2% exceeded 300 μg/L, with peak concentrations of 658 μg/L (284-1540). The Roche Opiates II immunoassay had efficiencies greater than 96% for the 2000 and 300 μg/L cutoffs. The CEDIA 6-AM immunoassay had a specificity of 91%, while the Lin-Zhi assay had no false positive results. These data provide valuable information for interpreting urine opiate results.


Drug Testing and Analysis | 2014

Cannabinoid Disposition in Oral Fluid after Controlled Cannabis Smoking in Frequent and Occasional Smokers

Matthew N. Newmeyer; Nathalie A. Desrosiers; Dayong Lee; Damodara Rao Mendu; Allan J. Barnes; David A. Gorelick; Marilyn A. Huestis

Oral fluid (OF) is an increasingly popular alternative matrix for drug testing, with cannabinoids being the most commonly identified illicit drug. Quantification of multiple OF cannabinoids and understanding differences in OF cannabinoid pharmacokinetics between frequent and occasional smokers improve test interpretation. The new Oral-Eze® OF collection device has an elution buffer that stabilizes analytes and improves drug recovery from the collection pad; however, its performance has not been independently evaluated. After controlled smoking of a 6.8% Δ(9) -tetrahydrocannabinol (THC) cannabis cigarette by frequent and occasional smokers, OF was collected with the Oral-Eze device for up to 30 h. Samples were analyzed for multiple cannabinoids by a validated 2D-GC-MS method. Frequent smokers had significantly greater OF THCCOOH concentrations than occasional smokers at all times, and showed positive results for a significantly longer time. We evaluated multiple cannabinoid cut-offs; the shortest last detection times were observed when THC ≥ 1 μg/L was combined with CBD or CBN ≥ 1 μg/L. With these cut-offs, last detection times(1-13.5 h) were not significantly different between groups, demonstrating suitability for short-term cannabinoid detection independent of smoking history. Cut-offs utilizing THC alone or combined with THCCOOH showed significantly different last detection times between groups. The widest detection windows were observed with THC ≥ 1 or 2 μg/L or THCCOOH ≥ 20 ng/L. Our data illustrate the effectiveness of the Oral-Eze® device for OF collection, the impact of self-administered smoked cannabis history on OF cannabinoid results, and the ability to improve interpretation and tailor OF cannabinoid cut-offs to fulfill the detection window needs of a given program.


Drug Testing and Analysis | 2017

Cannabinoid disposition in oral fluid after controlled smoked, vaporized, and oral cannabis administration

Madeleine J. Swortwood; Matthew N. Newmeyer; Maria Andersson; Osama A. Abulseoud; Karl B. Scheidweiler; Marilyn A. Huestis

Oral fluid (OF) is an important matrix for monitoring drugs. Smoking cannabis is common, but vaporization and edible consumption also are popular. OF pharmacokinetics are available for controlled smoked cannabis, but few data exist for vaporized and oral routes. Frequent and occasional cannabis smokers were recruited as participants for four dosing sessions including one active (6.9% Δ9 -tetrahydrocannabinol, THC) or placebo cannabis-containing brownie, followed by one active or placebo cigarette, or one active or placebo vaporized cannabis dose. Only one active dose was administered per session. OF was collected before and up to 54 (occasional) or 72 (frequent) h after dosing from cannabis smokers. THC, 11-hydroxy-THC (11-OH-THC), 11-nor-9-carboxy-THC (THCCOOH), tetrahydrocannabivarin (THCV), cannabidiol (CBD), and cannabigerol (CBG) were quantified by liquid chromatography-tandem mass spectrometry. OF cannabinoid Cmax occurred during or immediately after cannabis consumption due to oral mucosa contamination. Significantly greater THC Cmax and significantly later THCV, CBD, and CBG tlast were observed after smoked and vaporized cannabis compared to oral cannabis in frequent smokers only. No significant differences in THC, 11-OH-THC, THCV, CBD, or CBG tmax between routes were observed for either group. For occasional smokers, more 11-OH-THC and THCCOOH-positive specimens were observed after oral dosing than after inhaled routes, increasing % positive cannabinoid results and widening metabolite detection windows after oral cannabis consumption. Utilizing 0.3 µg/L THCV and CBG cut-offs resulted in detection windows indicative of recent cannabis intake. OF pharmacokinetics after high potency CBD cannabis are not yet available precluding its use currently as a marker of recent use. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.


Journal of Chromatography A | 2016

Quantification of cannabinoids and their free and glucuronide metabolites in whole blood by disposable pipette extraction and liquid chromatography-tandem mass spectrometry.

Karl B. Scheidweiler; Matthew N. Newmeyer; Allan J. Barnes; Marilyn A. Huestis

Identifying recent cannabis intake is confounded by prolonged cannabinoid excretion in chronic frequent cannabis users. We previously observed detection times ≤2.1h for cannabidiol (CBD) and cannabinol (CBN) and Δ(9)-tetrahydrocannabinol (THC)-glucuronide in whole blood after smoking, suggesting their applicability for identifying recent intake. However, whole blood collection may not occur for up to 4h during driving under the influence of drugs investigations, making a recent-use marker with a 6-8h detection window helpful for improving whole blood cannabinoid interpretation. Other minor cannabinoids cannabigerol (CBG), Δ9-tetrahydrocannabivarin (THCV), and its metabolite 11-nor-9-carboxy-THCV (THCVCOOH) might also be useful. We developed and validated a sensitive and specific liquid chromatography-tandem mass spectrometry method for quantification of THC, its phase I and glucuronide phase II metabolites, and 5 five minor cannabinoids. Cannabinoids were extracted from 200μL whole blood via disposable pipette extraction, separated on a C18 column, and detected via electrospray ionization in negative mode with scheduled multiple reaction mass spectrometric monitoring. Linear ranges were 0.5-100μg/L for THC and 11-nor-9-carboxy-THC (THCCOOH); 0.5-50μg/L for 11-hydroxy-THC (11-OH-THC), CBD, CBN, and THC-glucuronide; 1-50μg/L for CBG, THCV, and THCVCOOH; and 5-500μg/L for THCCOOH-glucuronide. Inter-day accuracy and precision at low, mid and high quality control (QC) concentrations were 95.1-113% and 2.4-8.5%, respectively (n=25). Extraction recoveries and matrix effects at low and high QC concentrations were 54.0-84.4% and -25.8-30.6%, respectively. By simultaneously monitoring multiple cannabinoids and metabolites, identification of recent cannabis administration or discrimination between licit medicinal and illicit recreational cannabis use can be improved.


Clinical Chemistry | 2017

Cannabis Edibles: Blood and Oral Fluid Cannabinoid Pharmacokinetics and Evaluation of Oral Fluid Screening Devices for Predicting Δ9-Tetrahydrocannabinol in Blood and Oral Fluid following Cannabis Brownie Administration

Matthew N. Newmeyer; Madeleine J. Swortwood; Maria Andersson; Osama A. Abulseoud; Karl B. Scheidweiler; Marilyn A. Huestis

BACKGROUND Roadside oral fluid (OF) Δ9-tetrahydrocannabinol (THC) detection indicates recent cannabis intake. OF and blood THC pharmacokinetic data are limited and there are no on-site OF screening performance evaluations after controlled edible cannabis. CONTENT We reviewed OF and blood cannabinoid pharmacokinetics and performance evaluations of the Draeger DrugTest®5000 (DT5000) and Alere™ DDS®2 (DDS2) on-site OF screening devices. We also present data from a controlled oral cannabis administration session. SUMMARY OF THC maximum concentrations (Cmax) were similar in frequent as compared to occasional smokers, while blood THC Cmax were higher in frequent [mean (range) 17.7 (8.0-36.1) μg/L] smokers compared to occasional [8.2 (3.2-14.3) μg/L] smokers. Minor cannabinoids Δ9-tetrahydrocannabivarin and cannabigerol were never detected in blood, and not in OF by 5 or 8 h, respectively, with 0.3 μg/L cutoffs. Recommended performance (analytical sensitivity, specificity, and efficiency) criteria for screening devices of ≥80% are difficult to meet when maximizing true positive (TP) results with confirmation cutoffs below the screening cutoff. TPs were greatest with OF confirmation cutoffs of THC ≥1 and ≥2 μg/L, but analytical sensitivities were <80% due to false negative tests arising from confirmation cutoffs below the DT5000 and DDS2 screening cutoffs; all criteria were >80% with an OF THC ≥5 μg/L cutoff. Performance criteria also were >80% with a blood THC ≥5 μg/L confirmation cutoff; however, positive OF screening results might not confirm due to the time required to collect blood after a crash or police stop. OF confirmation is recommended for roadside OF screening.ClinicalTrials.gov identification number: NCT02177513.


Drug Testing and Analysis | 2015

Morphine and Codeine in Oral Fluid after Controlled Poppy Seed Administration

Marta Concheiro; Matthew N. Newmeyer; Jose Luiz da Costa; Ron Flegel; David A. Gorelick; Marilyn A. Huestis

Opiates are an important drug class in drug testing programmes. Ingestion of poppy seeds containing morphine and codeine can yield positive opiate tests and mislead result interpretation in forensic and clinical settings. Multiple publications evaluated urine opiate concentrations following poppy seed ingestion, but only two addressed oral fluid (OF) results; neither provided the ingested morphine and codeine dosage. We administered two 45 g raw poppy seed doses, each containing 15.7 mg morphine and 3.1 mg codeine, 8 h apart to 17 healthy adults. All OF specimens were screened by on-site OF immunoassay Draeger DrugTest 5000, and confirmed with OF collected with Oral-Eze® device and quantified by liquid chromatography-tandem mass spectrometry (1 µg/L morphine and codeine limits of quantification). Specimens (n = 459) were collected before and up to 32 h after the first dose. All specimens screened positive 0.5 h after dosing and remained positive for 0.5-13 h at Draeger 20 µg/L morphine cut-off. Maximum OF morphine and codeine concentrations (Cmax ) were 177 and 32.6 µg/L, with times to Cmax (Tmax ) of 0.5-1 h and 0.5-2.5 h post-dose, respectively. Windows of detection after the second dose extended at least 24 h for morphine and to 18 h for codeine. After both doses, the last morphine positive OF result was 1 h with 40 µg/L 2004 proposed US Substance Abuse and Mental Health Services Administration cut-off, and 0.5 h with 95 µg/L cut-off, recently recommended by the Driving under the Influence of Drugs and Medicines project. Positive OF morphine results are possible 0.5-1 h after ingestion of 15.7 mg of morphine in raw poppy seeds, depending on the cut-off employed.


Drug Testing and Analysis | 2015

Oral fluid with three modes of collection and plasma methamphetamine and amphetamine enantiomer concentrations after controlled intranasal l-methamphetamine administration.

Matthew N. Newmeyer; Marta Concheiro; Jose Luiz da Costa; Ronald Flegel; David A. Gorelick; Marilyn A. Huestis

Methamphetamine is included in drug testing programmes due to its high abuse potential. d-Methamphetamine is a scheduled potent central nervous system stimulant, while l-methamphetamine is the unscheduled active ingredient in the over-the-counter nasal decongestant Vicks® VapoInhaler™. No data are available in oral fluid (OF) and few in plasma after controlled Vicks® VapoInhaler™ administration. We quantified methamphetamine and amphetamine enantiomers in OF collected with two different devices and plasma via a fully validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Additionally, OF were analyzed with an on-site screening device. Sixteen participants received 7 Vicks® VapoInhaler™ doses according to manufacturers recommendations. Specimens were collected before and up to 32 h after the first dose. No d-methamphetamine or d-amphetamine was detected in any sample. All participants had measurable OF l-methamphetamine with median maximum concentrations 14.8 and 16.1 μg/L in Quantisal™ and Oral-Eze® devices, respectively, after a median of 5 doses. One participant had measurable OF l-amphetamine with maximum concentrations 3.7 and 5.5 μg/L after 6 doses with the Quantisal™ and Oral-Eze® devices, respectively. There were no positive DrugTest® 5000 results. In the cutoff range 20-50 μg/L methamphetamine with amphetamine ≥limit of detection, 3.1-10.1% of specimens were positive; first positive results were observed after 1-4 doses. Two participants had detectable plasma l-methamphetamine, with maximum observed concentrations 6.3 and 10.0 μg/L after 2 and 5 doses, respectively. Positive OF and plasma methamphetamine results are possible after Vicks® VapoInhaler™ administration. Chiral confirmatory analyses are necessary to rule out VapoInhaler™ intake. Implementing a selective d-methamphetamine screening assay can help eliminate false-positive OF results.


Journal of Analytical Toxicology | 2014

Methamphetamine and Amphetamine Isomer Concentrations in Human Urine Following Controlled Vicks VapoInhaler Administration

Michael L. Smith; Daniel C. Nichols; Paula Underwood; Zachary J. Fuller; Matthew A. Moser; Ron Flegel; David A. Gorelick; Matthew N. Newmeyer; Marta Concheiro; Marilyn A. Huestis

Legitimate use of legal intranasal decongestants containing l-methamphetamine may complicate interpretation of urine drug tests positive for amphetamines. Our study hypotheses were that commonly used immunoassays would produce no false-positive results and a recently developed enantiomer-specific gas chromatography-mass spectrometry (GC-MS) procedure would find no d-amphetamine or d-methamphetamine in urine following controlled Vicks VapoInhaler administration at manufacturers recommended doses. To evaluate these hypotheses, 22 healthy adults were each administered one dose (two inhalations in each nostril) of a Vicks VapoInhaler every 2 h for 10 h on Day 1 (six doses), followed by a single dose on Day 2. Every urine specimen was collected as an individual void for 32 h after the first dose and assayed for d- and l-amphetamines specific isomers with a GC-MS method with >99% purity of R-(-)-α-methoxy-α-(trifluoromethyl)phenylacetyl derivatives and 10 µg/L lower limits of quantification. No d-methamphetamine or d-amphetamine was detected in any urine specimen by GC-MS. The median l-methamphetamine maximum concentration was 62.8 µg/L (range: 11.0-1,440). Only two subjects had detectable l-amphetamine, with maximum concentrations coinciding with l-methamphetamine peak levels, and always ≤ 4% of the parents maximum. Three commercial immunoassays for amphetamines EMIT(®) II Plus, KIMS(®) II and DRI(®) had sensitivities, specificities and efficiencies of 100, 97.8, 97.8; 100, 99.6, 99.6 and 100, 100, 100%, respectively. The immunoassays had high efficiencies, but our first hypothesis was not affirmed. The EMIT(®) II Plus assay produced 2.2% false-positive results, requiring an enantiomer-specific confirmation.


Clinical Chemistry | 2016

Free and Glucuronide Whole Blood Cannabinoids' Pharmacokinetics after Controlled Smoked, Vaporized, and Oral Cannabis Administration in Frequent and Occasional Cannabis Users: Identification of Recent Cannabis Intake

Matthew N. Newmeyer; Madeleine J. Swortwood; Allan J. Barnes; Osama A. Abulseoud; Karl B. Scheidweiler; Marilyn A. Huestis


Drug and Alcohol Dependence | 2017

Subjective and physiological effects, and expired carbon monoxide concentrations in frequent and occasional cannabis smokers following smoked, vaporized, and oral cannabis administration

Matthew N. Newmeyer; Madeleine J. Swortwood; Osama A. Abulseoud; Marilyn A. Huestis

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Marilyn A. Huestis

Thomas Jefferson University

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Madeleine J. Swortwood

National Institute on Drug Abuse

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Osama A. Abulseoud

National Institute on Drug Abuse

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Karl B. Scheidweiler

National Institute on Drug Abuse

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Allan J. Barnes

National Institute on Drug Abuse

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Marta Concheiro

National Institute on Drug Abuse

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Jose Luiz da Costa

National Institute on Drug Abuse

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Maria Andersson

National Institute on Drug Abuse

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Damodara Rao Mendu

Memorial Sloan Kettering Cancer Center

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