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2.
Forensic Sci Int ; 196(1-3): 64-9, 2010 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-20083362

RESUMO

INTRODUCTION: Opiate hair analysis continues to prove difficult due to the scarcity of hair sample and low drug concentrations. For this reason, we developed a sensitive method utilizing headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) for the detection of three principle opiates; codeine, morphine, and 6-acetylmorphine. METHODS: Experimental conditions for HS-SPME and GC-MS were systematically optimized to produce the sensitive analytical method reported. Briefly, opiates were extracted from adult hair with methanol under agitation. The methanolic extract was then decanted into SPME autosampler vials, where deuterated standards of each of the 3 opiates were added at a concentration of 2 ng/mg. Samples were dried under N(2), derivatized, and subjected to HS-SPME coupled with GC/MS for analysis. RESULTS: Preliminary datum for this study indicates detection limits for these 3 opiates are superior to that reported in the literature; an LOQ of 0.01 ng/mg for morphine and 6-acetylmorphine and 0.005 ng/mg for codeine. Linearity was evident between 0.01 ng/mg and 5 ng/mg for each opiate, with R(2) above 0.992. The robustness of the method was demonstrated to be acceptable as inter-day and intra-day precision fell below 15% for each opiate analyzed. CONCLUSION: Compared with conventional methods, this method of detection for opiates is fast, simple, and accurate, with the sensitivity and specificity required in forensic and clinical toxicology.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Cabelo/química , Entorpecentes/análise , Microextração em Fase Sólida , Adulto , Codeína/análise , Toxicologia Forense , Humanos , Morfina/análise , Derivados da Morfina/análise , Detecção do Abuso de Substâncias/métodos
3.
Forensic Sci Int ; 189(1-3): 24-7, 2009 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-19482449

RESUMO

UNLABELLED: Methods that employ detection of drugs of abuse in hair are important for monitoring compliance with drug abstinence. Understanding the mechanisms and timeline of drug disappearance from hair is critical for clinical and forensic application of hair testing. We aimed to evaluate the kinetics of disappearance of cocaine and its metabolite, benzoylecgonine (BE), from hair after discontinuation of drug use. METHODS: The Motherisk laboratory at the Hospital for Sick Children in Toronto routinely receives hair samples for toxicology analysis. Cocaine and BE hair results were obtained from the Motherisk Database for calculation of half-life of these compounds in hair. Subjects were included in the study if they had gradually decreasing concentrations of cocaine and/or BE in sequential hair samples, with higher levels in the 1-3 cm distal segments (i.e. earlier in time) and low or non-measurable levels in the segment closest to the scalp (i.e. closer to the date of sampling). Elimination half-life of cocaine and BE in hair was calculated using standard kinetics calculations. The study was anonymous, and received ethics approval by the Ethics Review Board of our institution. RESULTS: 137 subjects met the inclusion criteria for the study. The median half-life of cocaine in hair was 1.5 months (95% CI 1.2-1.8) in females and 1.5 months (95% CI 1.1-1.8) in males. The median half-life of BE was 1.5 months (95% CI 1.1-2) in females and 1.5 months (95% CI 0.8-1.8) in males. Half lives of cocaine or BE were not statistically different between males and females (Mann-Whitney U-test; P=0.93 for cocaine, P=0.99 for BE). Half lives of cocaine and BE were strongly correlated (Spearman rank rho=0.73; P<0.001). CONCLUSION: Cocaine and BE could be detected in hair of former drug users for several months after abstinence. The calculated half-life of over 1 month for cocaine implies that, assuming first order elimination, approximately 3-4 months have to pass for hair testing to become negative in the segment proximal to the scalp. This finding should be incorporated in interpreting compliance with abstinence of former drug users, and suggests that caution has to be exerted when evaluating potential breaches of abstinence.


Assuntos
Cocaína/farmacocinética , Inibidores da Captação de Dopamina/farmacocinética , Cabelo/química , Detecção do Abuso de Substâncias , Cocaína/análogos & derivados , Cocaína/análise , Transtornos Relacionados ao Uso de Cocaína , Inibidores da Captação de Dopamina/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Toxicologia Forense , Meia-Vida , Humanos , Masculino
4.
Arch Dis Child Fetal Neonatal Ed ; 92(5): F351-5, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17077112

RESUMO

BACKGROUND: Methamphetamine misuse is a serious health problem of epidemic proportions. Use of this drug, particularly during pregnancy, is difficult to ascertain. Sparse information is available on gestational exposure. OBJECTIVES: To quantify methamphetamine accumulation in hair, identify the use of methamphetamine with other drugs of abuse and characterise correlations between concentrations of methamphetamine in maternal and neonatal hair. SUBJECTS AND METHODS: Motherisk laboratory at the Hospital for Sick Children routinely carries out analysis of methamphetamine in hair. Mothers and infants with positive results for methamphetamine in hair were identified. Drugs present in hair were analysed by ELISA and positive results were confirmed by gas chromatgraphy/mass spectrometry. RESULTS: 396 people positive for methamphetamine in their hair were identified from our database. Almost 85% of them were positive for at least one other drug of abuse, mostly cocaine. Eleven mother-baby pairs with hair positive for methamphetamine were identified. Methamphetamine levels in hair ranged between 0.13 and 51.97 ng/mg in the mothers and between 0 and 22.73 ng/mg in the neonates. Methamphetamine levels in mothers and neonates correlated significantly. One (9%) neonate was negative for methamphetamine even though the mother was positive. CONCLUSION: To our knowledge, this is the first report on fetal exposure to methamphetamine during pregnancy, showing transplacental transfer of the drug, with accumulation in fetal hair. Hair measurement for methamphetamine in neonates is a useful screening method to detect intra-uterine exposure to the drug. The data also indicate that positive exposure to methamphetamine strongly suggests that the person is a polydrug user, which may have important implications for fetal safety.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Feto/efeitos dos fármacos , Cabelo/química , Exposição Materna/efeitos adversos , Metanfetamina/análise , Complicações na Gravidez/metabolismo , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Cocaína/análise , Inibidores da Captação de Dopamina/análise , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Troca Materno-Fetal/fisiologia , Gravidez
5.
Arch Dis Child Fetal Neonatal Ed ; 88(2): F98-F100, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12598495

RESUMO

BACKGROUND: Meconium and hair are two biological markers of in utero exposure to illicit drugs. OBJECTIVE: To compare the sensitivity of the two tests for different drugs. SETTING: Motherisk laboratory which tests in utero drug exposure in Toronto. METHODS: Cocaine, benzoylecgonine, opiates, cannabis, benzodiazepines, methadone, and barbiturates were measured in pairs of hair and meconium samples from the same neonates. RESULTS: Meconium was marginally more sensitive than neonatal hair for detection of cocaine and cannabis, possibly because it may detect second trimester exposure whereas hair grows only during the third trimester of pregnancy. There was a significant correlation between hair and meconium concentrations of cocaine, cannabis, and opiates. CONCLUSION: In cases of clinical suspicion and a negative neonatal urine test, both meconium and hair are effective biological markers of in utero illicit drug exposure. Meconium may be more sensitive, but neonatal hair is available for three months whereas meconium is available for only one or two days. In contrast, the use of meconium, being a discarded material, is more acceptable to some parents than hair testing, which entails cutting scalp hair from the newborn.


Assuntos
Cabelo/química , Drogas Ilícitas/análise , Mecônio/química , Cannabis , Cocaína/análise , Humanos , Recém-Nascido , Modelos Lineares , Entorpecentes/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Can J Physiol Pharmacol ; 79(11): 942-5, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11760096

RESUMO

There is wide variability in the reported adverse fetal effects of cocaine and cannabinoids. The causes of this variability are largely unknown. We hypothesized that variability in placental handling of drugs affect fetal exposure. We used twin pregnancies as a paradigm to address the role of the placenta in this variability. We analyzed hair or meconium samples taken from dizygotic and monozygotic twins exposed in utero to illicit drugs. Out of 12 pairs, 5 had negative levels in both twins, and seven pairs of twins had chemical evidence of fetal exposure to cocaine (n = 5) or cannabinoids (n = 2). The one known monozygotic pair of twins had almost identical levels of cocaine. In contrast, the six dizygotic pairs had large disparities in either cocaine or cannabinoid concentrations. In three of these six dizygotic pairs, levels of cocaine (n = 2) or canabinoids (n = 1) were undetectable in one twin while positive in the other. Given that twins are theoretically exposed to similar maternal drug levels, our findings suggest that the placenta may have a major role in modulating the amounts of drug reaching the fetus.


Assuntos
Canabinoides/farmacocinética , Cocaína/farmacocinética , Troca Materno-Fetal , Placenta/metabolismo , Canabinoides/análise , Cocaína/análise , Feminino , Cabelo/química , Humanos , Recém-Nascido , Masculino , Mecônio/química , Placenta/fisiologia , Circulação Placentária , Gravidez , Gêmeos Dizigóticos , Gêmeos Monozigóticos
7.
Forensic Sci Int ; 107(1-3): 281-8, 2000 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-10689580

RESUMO

During the last 2 decades there has been a substantial increase in illicit drug consumption in North America. It has been repeatedly shown that the personal history of drug use is far from being accurate. Fearing legal consequences and embarrassment of admitted illicit substance use, most users tend to deny or, to under-report illicit drug consumption. These facts have stressed an urgent need for a biological marker which does not lose its sensitivity within a few days after the end of exposure and which may yield a cumulative reflection of long term exposure to illicit drugs. Hair analysis has emerged as such a marker. A variety of illicit and medicinal compounds have been shown to be incorporated into hair including trace metals, barbiturates, amphetamines, opiates, phencyclidine, cocaine, nicotine and cannabis. Hair analysis for drugs of abuse provides long-term information on an individual's drug use; its window of detection is limited only by the length of the hair and typically, ranges from a week to several months. After establishing and validating several hair tests during the last decade, we have analyzed over 1000 hair samples for different drugs of abuse. We used RIA for screening and GC-MS for confirmation of positive results. The aim of this report is to illustrate the diagnostic usefulness of hair testing in different age groups (newborns, children, adults) and circumstances: (criminal cases, athletes, child custody cases, etc.).


Assuntos
Cabelo/química , Drogas Ilícitas/análise , Detecção do Abuso de Substâncias , Adulto , Canadá , Crime , Feminino , Medicina Legal , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Complicações na Gravidez , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/reabilitação
8.
Ther Drug Monit ; 21(6): 644-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10604826

RESUMO

The authors report testing the meconium of a newborn for the presence of FAEE. Meconium from a newborn of a woman who acknowledged drinking beer throughout pregnancy was tested. The authors also tested the meconiums of 3 newborns whose mothers did not drink at all while pregnant. The FAEE were extracted from the meconium samples using solid phase extraction (SPE), and were identified and quantitated by gas chromatography with flame ionization detection (FID). For assignment of retention times and determination of individual concentrations, authentic mixtures of FAEE were injected. The total FAEE concentration in the meconium of the alcohol-exposed infant was 13126 ng/g compared to a mean of 410 ng/g in the control meconiums. Also, in this case, palmitic, linoleic, and stearic ethyl esters were found in the alcohol-exposed infant's meconium while they were not found in the unexposed infant's meconium. In a parallel experiment, the authors spiked increasing amounts of ethyl alcohol (0-40mM) into the meconium from a newborn that was not exposed to ethanol in utero. The spiked samples were incubated for 4 hours at 37 degrees C and subsequently assayed for the presence of ethyl linoleate. In these experiments, they document for the first time that FAEE is produced in meconium. If confirmed by large studies, FAEE may become the first neonatal biologic marker for babies at risk for alcohol-related birth defects.


Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Etanol/metabolismo , Ácidos Graxos/análise , Mecônio/química , Complicações na Gravidez/metabolismo , Biomarcadores , Cromatografia Gasosa , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Ácido Linoleico/análise , Ácidos Linoleicos/análise , Masculino , Troca Materno-Fetal , Ácido Palmítico/análise , Gravidez , Ácidos Esteáricos/análise
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