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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Estudo do comportamento eletroquímico do 9-tetraidrocanabinol derivatizado com Fast Blue B / Study of electrochemical behavior of 9-tetrahydrocannabinol derivatizated with Fast Blue B

Marco Antonio Balbino 29 October 2014 (has links)
A maconha é a droga ilícita mais consumida no mundo, tem como substância psicoativa o delta-9-tetraidrocanabinol (9-THC). Os testes colorimétricos são normalmente realizados em amostras de maconha (e para qualquer outra droga ilícita) apreendidas. A adição de reagentes específicos em uma solução de extrato de maconha pode indicar a presença de substância ilícita mediante mudança de cor. No entanto, a literatura recentemente tem relatado ocorrências de resultados falso-positivos quando os testes colorimétricos são aplicados em algumas folhagens de diversas espécies de plantas. Este estudo utilizou as técnicas voltamétricas em meio orgânico N-N-dimetilformamida utilizando tetrafluoroborato de tetrabutilamônio como eletrólito de suporte e eletrodos de trabalho de disco de carbono vítreo e platina. Aplicando-se um potencial de pré concentração em - 0,5 V, verifica-se um pico de corrente anódica em ± 0,01 V vs Ag/AgCl ,KCl(sat). Utilizando eletrodo de disco de carbono vítreo como eletrodo de trabalho, na modalidade de onda quadrada, obteve-se uma dependência linear na faixa de concentração entre 1,0 x 10-9 mol L-1 a 2,2 x 10-8 mol L-1, com um coeficiente de correlação linear em 0,999 e um limite de detecção de 6,2 x 10-10 mol L-1. Tais resultados possibilitaram a determinação de 9-THC na ordem de nmol L-1. / Marijuana, the illicit drug that is most consumed worldwide, contains 9-tetrahydrocannabinol (9-THC) as the main psychoactive substance. Presumptive colorimetric tests are usually performed on seized marijuana (or any illicit drug) samples: the addition of specific reagents to the marijuana extract solution prompts a change in. This study was developed using voltammetric techniques in organic medium (N,N-dimethylformamide) using tetrabutylammonium tetrafluoroborate (TBATFB) as supporting electrolyte, and glassy carbon and platinum disc as working electrode. Applying a pre-concentration potential of -0.5 by square-wave voltammetry, we detected a well-defined anodic peak current in ± 0.01 V versus Ag/AgCl, KCl(sat); 9-THC detection presented linear dependence at concentrations ranging from 1.0 × 10-9 mol L-1 to 2.2 × 10-8 mol L-1, with a linear correlation coefficient 0.999 and a detection limit of 6.2 × 10-10 mol L-1, using the glassy carbon disc working electrode.
32

Characterization of Cannabinoid Receptor 2 Transcript Expression in B Cells

Sherwood, Tracy 29 March 2010 (has links)
Cannabinoids and cannabinoid receptors have been shown to play important roles in immune regulation particularly as modulators of anti-inflammatory cytokines and antibody production. The predominant cannabinoid receptor involved in this immune regulation is cannabinoid receptor 2 (CB2), which is robustly expressed in B cells. Utilizing a combination of bioinformatics, 5' RACE, real time RT-qPCR, and reporter assays, we showed that human B cells from peripheral blood mononuclear cells (PBMC) expressed one CB2 transcript while mouse B cells from spleen express three CB2 transcripts. Alignment of the sequenced B cell RACE products to either the mouse or human genome, along with the GenBank mRNA sequences, revealed that the transcripts isolated in this study contained previously unidentified transcriptional start sites (TSSs). In addition, expression construct testing of the genomic region containing the TSSs of the mouse CB2 exon 1 and 2 transcripts showed a significant increase of promoter activity. Bioinformatics analysis for cis-sequences in the promoter regions identified DNA binding sites for NF-kB, STAT6, and Elk1 transcription factors activated by LPS, IL-4 and anti-CD40. Regarding variations in CB2 transcript expression among the immune cell subtypes, RACE analysis showed that the exon 1b transcript is seen in B cells but not in T cells, dendritic cells or macrophages. Furthermore, RT-qPCR showed variations in transcript expression during B cell development as well as in resting versus LPS or IL-4/anti-CD40 stimulated B cells. The exon 1a transcript was predominant in pre-, immature and resting B cells whereas the exon 1b and 2 transcripts were enhanced in mature and activated B cells. These data showed for the first time that human B cells use one TSS for CB2 expression while mouse B cells use multiple TSSs for the expression of three CB2 transcripts, in which the expression of the individual transcript is related to immune cell type and/or cell activation state. Additionally, this is the first report in mouse B cells defining TSSs that are in genomic areas with promoter activity thus suggesting the location of two promoter regions. Defining the CB2 transcript expression during various stages of B cell activation provide clues to therapeutic methods.
33

The Effects of Marihuana Extract Distillate on Eating Behavior of Rats

Wetle, Terrie 30 June 1971 (has links)
Since hunger drive is often used as a motivating factor in animal learning experimentation, it was decided to determine the effects of marihuana extract distillate on the eating behavior of rats. Carlini and Kramer (1965) found marihuana extract injections to have a faciliatory effect upon maze performance. They suggested that facilitation could have resulted from and increase in hunger drive. However, if the dosage level is high, this effect may last for a short time and be followed by a disinterest in food. Scheckel et al. (1968) report that some monkeys, at very high dosage levels of tetrahydrocannabinol starved to death in post-drug depressions. Human studies indicate some increased hunger or "taste enhancement" (Grinspoon, 1968; Hollister, et al., 1968; Ames, 1958). Ss were 20 male and 20 female adult Sprague-Dawley albino rats, maintained in home cages with ad-lib food and water. Each animal was assigned to one of five groups so that each group contained four males and four females. Each group received one dosage level of the drug throughout the entire experiment. Three dosage levels and two controls were used. Food deprivation levels of ad-lib, 12, 24, and 48 hours were assigned according to a balanced Latin square design. The drug, marihuana extract distillate, was administered through an intraesophogeal tube and hypodermic syringe. The study was divided into two parts, each of four weeks' duration. In the first, after administration of the frug, the animals immediately were placed into a cage with a known amount of food present. The food was weighed after three and 24 hours to determine the amount of food eaten. The second experiment in the study repeats all proc3edures except animals were not given food until 1/2-hour after the drug was administered. Results show an inverse relationship between dosage level of marihuana extract distillate and amount of food eaten. Effects of dosage level, hours of deprivation, sex, latency of food preparation, and the possibility of tolerance or increased sensitivity to the drug are discussed.
34

Desenvolvimento e validação de metodologia analítica para a determinação de canabidiol e tetraidrocanabinol em amostras de plasma por cromatografia em fase gasosa/espectrometria de massas / Development and validation of an analytical methodology for determination of cannabidiol and tetrahydrocanabinol in plasma samples using gas phase chromatografy /mass espectrometry

Camargo, Stefania Pimenta Serrambana 10 October 2008 (has links)
O Canabidiol (CBD), que representa aproximadamente 40% dos canabinóides encontrados na planta Cannabis sativa, é desprovido dos efeitos psicológicos e cognitivos típicos do 9-Tetraidrocanabinol (9THC). Estudos sugerem que o CBD apresenta propriedades ansiolíticas, porém esta substância nunca foi testada na ansiedade clínica. Do mesmo modo, não se sabe como estes possíveis efeitos seriam mediados centralmente em pacientes com transtorno de ansiedade social (TAS). Diante das evidências da existência de um sistema canabinóide em humanos e do crescente interesse terapêutico no uso do CBD, justifica-se um estudo para desenvolvimento e validação de uma metodologia analítica para a determinação e quantificação de CBD e 9THC empregando a técnica de cromatografia em fase gasosa/espectrometria de massas. O método desenvolvido e validado se mostrou rápido, simples, de baixo custo com boa sensibilidade e apropriado para aplicação na área da toxicologia clínica. O método demonstrou ser linear no intervalo de concentração de 5 a 500 ng/0,5 mL de plasma para o CBD (r2 = 0,99) e de 5 a 300 ng/0,5 mL (r2 = 0,98) para o 9THC. Os limites de detecção e quantificação foram respectivamente 0,1 ng/0,5 mL e 0,5 ng/0,5 mL para o CBD e, 5 ng/0,5 mL e 10 ng/0,5 mL para o 9THC. Valores de precisão inter e intra ensaio estão respectivamente, na faixa de 5,5% a 12,7%, e de 2,1% a 8,1%. Valores de exatidão inter e intra ensaio estão respectivamente, na faixa de 1,2% a 12,0, e de 1,2 a 14,5 para CBD e 9THC. A eficiência da extração foi obtida na faixa de 54,6 a 93,2% de recuperação para os analitos. A metodologia validada foi empregada em um estudo clínico para correlacionar a dose após a administração controlada de CBD em pacientes com transtorno de ansiedade social. / Dissertation (Master). Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo, Ribeirão Preto, 2008. The Cannabidiol (CBD), that represents about 40% of the cannabinoids found in Cannabis sativa plant, is devoided of the typical psychological and cognitive effects of 9-Tetrahydrocannabinol (9THC). Researches suggest that CBD shows ansiolitic properties, but this substance was never tested on clinical anxiety. It is unknown how possible CBD effects could be centrally mediated in social anxiety disorder (SAD) patients. There are evidences about the existence of a cannabinoid system in humans and there is also increasing interest on therapeutic CBD application. The present study was conducted to develop and validate an analytical methodology for determination and quantification of CBD and 9THC, employing gas phase chromatography/mass spectrometry technique. The validated method was fast, easy, low cost, with a good sensibility and appropriate for clinical toxicology applications. The method was linear on the range of 5 to 500 ng/0,5 mL of plasma for CBD (r2=0,99) and 5 to 300 ng/0,5 mL (r2=0,98) for 9THC. The detection and quantification limits were 0,1 ng/0,5 mL and 0,5 ng/0,5 mL for CBD and 5ng/0,5 mL and 10 ng/0,5 mL for 9THC respectively. Inter and intraday reproducibility were between 5,5% to 12,7% and 2,1% to 8,1%, respectively. Inter and intraday accuracy was between 1,2% to 12% and 1,2% to 14,5% for CBD and 9THC respectively. The recovery of extraction was between 54, 6% to 93,2% of recovery for the analytes The validated methodology was applied in a clinical trial to correlate the doses after the controlled cannabidiol administration to patients with social anxiety disorders.
35

Cannabinoids suppress dendritic cell-induced T helper cell polarization /

Lu, Tangying (Lily). January 2006 (has links)
Dissertation (Ph.D.)--University of South Florida, 2006. / Includes vita. Includes bibliographical references (leaves 86-105). Also available online.
36

Drogy a činnosti, při nichž by mohl být ohrožen život nebo zdraví nebo poškozen cizí majetek / Drugs and activities that could cause danger to life, health or damage to property

HANDSCHUHOVÁ, Silvie January 2008 (has links)
The objective of this thesis is to summarize the effects of drugs, especially of the cannabinoids and amphetamine type stimulants, and to analyse which of these substances leads to high-risk activities, that could endanger life, health or result in damage to property. One of these activities, an important one, is driving under the influence of drugs. Driving itself is a complex demand, involving perception, decision making, psychomotor skills, knowledge, as well as attitudes and personality characteristics. Substance use and abuse has an impact on the functioning of the brain and mental processes and therefore on the performance of the driving task. Driving under the influence of drugs is a high risk activity which endangers not only the driver but also their surroundings. In the last few years, the Czech Republic registered a rapid increase in the number of impaired drivers, namely at police check points and in car accidents. The young drivers are mostly under influence of marijuana, respectively tetrahydrocannabinol (THC). Its negative effect on driving results from impaired co-ordination, slowed complex reaction time and in space and time distortion. The second group of drugs which can impair drivers is amphetamine type stimulants. Amphetamines are frequently sought by truck drivers, especially long-haul drivers, in Western Europe for its stimulative effects. In the Czech Republic the methamphetamine, Pervitin, is much more common. Intoxication is characterized by increased wakefulness, increased physical activity, increased respiration, rapid heart rate and an irregular heartbeat. The risk factors for driving are a lack of concentration and an overestimation of one{\crq}s own capabilities. After the acute phase of intoxication subsides, fatigue or states of narcolepsy may occur. Another amphetamine-based drug is methylenedioxymethamphetamine, MDMA or Ecstasy. This synthetic substance, chemically related to mescaline, is dangerous due to its ability to regulate body temperature. On rare but unpredictable occasions, this can lead to sharp hyperthermia, resulting in liver, kidney and cardiovascular system failure, and death. It can also cause hallucinations. All common drugs are easily detectable with ``drug test-cards{\crqq}, which are used during police checks around the the world. The Czech Republic is currently testing their utilization and is preparing legislation accordingly. Utilization of these tests during random checks could help to decrease the number of fatal road accidents and could help to decrease the number of impaired drivers on the roads.
37

Desenvolvimento e validação de metodologia analítica para a determinação de canabidiol e tetraidrocanabinol em amostras de plasma por cromatografia em fase gasosa/espectrometria de massas / Development and validation of an analytical methodology for determination of cannabidiol and tetrahydrocanabinol in plasma samples using gas phase chromatografy /mass espectrometry

Stefania Pimenta Serrambana Camargo 10 October 2008 (has links)
O Canabidiol (CBD), que representa aproximadamente 40% dos canabinóides encontrados na planta Cannabis sativa, é desprovido dos efeitos psicológicos e cognitivos típicos do 9-Tetraidrocanabinol (9THC). Estudos sugerem que o CBD apresenta propriedades ansiolíticas, porém esta substância nunca foi testada na ansiedade clínica. Do mesmo modo, não se sabe como estes possíveis efeitos seriam mediados centralmente em pacientes com transtorno de ansiedade social (TAS). Diante das evidências da existência de um sistema canabinóide em humanos e do crescente interesse terapêutico no uso do CBD, justifica-se um estudo para desenvolvimento e validação de uma metodologia analítica para a determinação e quantificação de CBD e 9THC empregando a técnica de cromatografia em fase gasosa/espectrometria de massas. O método desenvolvido e validado se mostrou rápido, simples, de baixo custo com boa sensibilidade e apropriado para aplicação na área da toxicologia clínica. O método demonstrou ser linear no intervalo de concentração de 5 a 500 ng/0,5 mL de plasma para o CBD (r2 = 0,99) e de 5 a 300 ng/0,5 mL (r2 = 0,98) para o 9THC. Os limites de detecção e quantificação foram respectivamente 0,1 ng/0,5 mL e 0,5 ng/0,5 mL para o CBD e, 5 ng/0,5 mL e 10 ng/0,5 mL para o 9THC. Valores de precisão inter e intra ensaio estão respectivamente, na faixa de 5,5% a 12,7%, e de 2,1% a 8,1%. Valores de exatidão inter e intra ensaio estão respectivamente, na faixa de 1,2% a 12,0, e de 1,2 a 14,5 para CBD e 9THC. A eficiência da extração foi obtida na faixa de 54,6 a 93,2% de recuperação para os analitos. A metodologia validada foi empregada em um estudo clínico para correlacionar a dose após a administração controlada de CBD em pacientes com transtorno de ansiedade social. / Dissertation (Master). Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo, Ribeirão Preto, 2008. The Cannabidiol (CBD), that represents about 40% of the cannabinoids found in Cannabis sativa plant, is devoided of the typical psychological and cognitive effects of 9-Tetrahydrocannabinol (9THC). Researches suggest that CBD shows ansiolitic properties, but this substance was never tested on clinical anxiety. It is unknown how possible CBD effects could be centrally mediated in social anxiety disorder (SAD) patients. There are evidences about the existence of a cannabinoid system in humans and there is also increasing interest on therapeutic CBD application. The present study was conducted to develop and validate an analytical methodology for determination and quantification of CBD and 9THC, employing gas phase chromatography/mass spectrometry technique. The validated method was fast, easy, low cost, with a good sensibility and appropriate for clinical toxicology applications. The method was linear on the range of 5 to 500 ng/0,5 mL of plasma for CBD (r2=0,99) and 5 to 300 ng/0,5 mL (r2=0,98) for 9THC. The detection and quantification limits were 0,1 ng/0,5 mL and 0,5 ng/0,5 mL for CBD and 5ng/0,5 mL and 10 ng/0,5 mL for 9THC respectively. Inter and intraday reproducibility were between 5,5% to 12,7% and 2,1% to 8,1%, respectively. Inter and intraday accuracy was between 1,2% to 12% and 1,2% to 14,5% for CBD and 9THC respectively. The recovery of extraction was between 54, 6% to 93,2% of recovery for the analytes The validated methodology was applied in a clinical trial to correlate the doses after the controlled cannabidiol administration to patients with social anxiety disorders.
38

Dispozice a metabolismus kanabinoidů. / Disposition and metabolism of cannabinoids.

Hložek, Tomáš January 2019 (has links)
This thesis describes in the form of a commentary on own original publications research on the problems of cannabinoids, ie. phytocannabinoids and some synthetic cannabinoids, their pharmacokinetics and effects. The work consists of four thematic areas: the pharmacokinetics of delta-9- tetrahydrocannabinol (THC) and cannabidiol (CBD) in rats, depending on the route of administration; THC concentration time profile in humans (after inhalation) and implications for transport safety; the pharmacokinetic profile of synthetic cannabinoids in rats; extraction and determination of phytocannabinoids in plant material. The first part of the thesis was to determine pharmacokinetic profiles of THC, CBD and combination thereof (1:1 weight ratio) in rats with respect to administration common in humans, i.e. inhalation, oral and subcutaneous administration. THC, its metabolites (11-hydroxy-tetrahydrocannabinol, 11-OH-THC; 11-nor-delta-9- carboxytetrahydrocannabinol, THCOOH) and CBD concentrations in serum and brains of animals were monitored at the 24 hours experimental interval during the study. Except for inhalation administration, co-administration of CBD inhibited THC metabolism (after both oral and subcutaneous), resulting in an increase in THC concentrations in both serum and brain of the rats relative to...
39

Uso da extração acelerada por solvente (ASE) para determinação cromatográfica de analitos de cocaína e tetraidrocanabinol em amostras de mecônio / Accelerated solvent extraction (ASE) for chromatographic analysis of cocaine and tetrahydrocannabinol analytes in meconium samples

Mantovani, Cínthia de Carvalho 15 May 2014 (has links)
O consumo de drogas de abuso é grave problema de saúde pública em todo o mundo. No Brasil observa-se aumento no número de usuárias em idade fértil, levando a crescente preocupação com relação à exposição fetal. Efeitos deletérios como diminuição do peso e crescimento fetal, parto prematuro, déficits neurológicos e comportamentais estão associados ao uso de cocaína e cannabis durante a gestação. Portanto, é importante obter informações acerca do consumo de drogas durante a gravidez, permitindo intervenções médicas e psicológicas adequadas. Os relatos fornecidos pelas gestantes são relevantes, porém muitas vezes resultam em dados subestimados devido à omissão de informações por medo de ações punitivas. Desta forma, a confirmação por meio de análises toxicológicas em amostras biológicas se faz necessária. O mecônio, primeiras fezes do recém-nascido, tem sido proposto como matriz adequada para avaliação da exposição fetal, pois apresenta coleta não invasiva, fácil obtenção e fornece informações de longo prazo (2º e 3º trimestre de gestação). Entretanto, é uma matriz complexa, exigindo diversas etapas de purificação para posterior análise. No presente trabalho, métodos analíticos foram desenvolvidos visando à detecção dos biomarcadores da exposição fetal à cocaína e ao tetraidrocanabinol em amostras de mecônio por cromatografia gasosa acoplada à espectrometria de massas (GC-MS). Para ambos os métodos, a extração acelerada por solvente (ASE) foi utilizada para o isolamento dos analitos de interesse de amostras de mecônio, já que esta apresenta vantagens frente às técnicas convencionais, devido sua maior eficiência e menor manipulação da amostra. Associada à ASE, a extração em fase sólida (SPE) foi empregada para purificação e concentração dos analitos de interesse. Na etapa de desenvolvimento, inicialmente foram estabelecidos os procedimentos de derivatização e as condições cromatográficas a serem empregadas nas análises. Posteriormente, realizou-se a otimização dos procedimentos empregados na ASE, através de análise de superfície de resposta. Os métodos foram validados de acordo com o preconizado por referências internacionais, estabelecendo-se os limites de detecção e quantificação, recuperação, linearidade, precisão intra e interensaio e exatidão. O método para detecção dos biomarcadores da cocaína foi aplicado em 342 amostras de mecônio, provenientes do Hospital Universitário da Universidade de São Paulo (HU-USP). Destas, 19 (5,6%) apresentaram resultado positivo para um ou mais biomarcadores da exposição fetal à cocaína. Além disto, foi observada redução estatisticamente significante do peso ao nascimento, comprimento e perímetro cefálico entre os recém-nascidos expostos à cocaína durante a gestação. O método para a detecção da exposição fetal ao tetraidrocanabinol foi aplicado em 6 amostras positivas, obtidas do HU-USP, mostrando a aplicabilidade da técnica desenvolvida. / The use of illicit drugs is a relevant public health problem in the world. In Brazil, the number of women users in fertile age is increasing, which leads to a growing concern regarding fetal drug exposure. Adverse outcomes such as low birth weight, intra-uterine growth restriction, preterm birth, neurobehavioral and developmental deficits are associated with cocaine and cannabis use during pregnancy. Consequently, it would be important to obtain data related to drug misuse during gestation with the aim to plan medical and psychological interventions. Self-report drug use by pregnant women is often inaccurate due to feelings of guilt or fear of punitive actions. Therefore, confirmation by toxicological analysis in biological matrices must be accomplished. Meconium, the first stool of the newborn, has been proposed as a proper matrix to evaluate fetal exposure because it is collected by an easy and non-invasive way and enables the achievement of long-term information regarding fetal exposure. However, meconium is a complex matrix, which requires extensive sample cleaning previously to the analytes identification. In the present research, analytical methods were developed aiming the determination of cocaine and tetrahydrocannabinol biomarkers in meconium samples through gas chromatography-mass spectrometry (GC-MS). Accelerated solvent extraction (ASE) was used for analytes isolation due to its advantages over conventional techniques, such as greater extraction efficiency and minor sample handling. In order to achieve proper analytes selectivity and detectability, solid phase extraction (SPE) was employed for post-extraction clean-up. Initially, the derivatization procedure and chromatographic parameters were established for the development of the methods. Afterwards, ASE procedure was optimized through response surface methodology. The analytical methods were validated in accordance to international references. Limits of detection and quantification, recovery, linearity, precision and accuracy were obtained. The developed method for cocaine was applied in 342 meconium samples collected from the University Hospital of University of São Paulo (HU-USP). Among them, 19 (5.6%) showed positivity result for cocaine biomarkers. Additionally, newborns from mothers exposed to cocaine exhibited statistical significant lower birth weight, length and head circumference when compared with newborns from non-consumer mothers. For the method of tetrahydrocannabinol, applicability and importance was demonstrated by analyzing 6 positive samples from HU-USP.
40

Uso da extração acelerada por solvente (ASE) para determinação cromatográfica de analitos de cocaína e tetraidrocanabinol em amostras de mecônio / Accelerated solvent extraction (ASE) for chromatographic analysis of cocaine and tetrahydrocannabinol analytes in meconium samples

Cínthia de Carvalho Mantovani 15 May 2014 (has links)
O consumo de drogas de abuso é grave problema de saúde pública em todo o mundo. No Brasil observa-se aumento no número de usuárias em idade fértil, levando a crescente preocupação com relação à exposição fetal. Efeitos deletérios como diminuição do peso e crescimento fetal, parto prematuro, déficits neurológicos e comportamentais estão associados ao uso de cocaína e cannabis durante a gestação. Portanto, é importante obter informações acerca do consumo de drogas durante a gravidez, permitindo intervenções médicas e psicológicas adequadas. Os relatos fornecidos pelas gestantes são relevantes, porém muitas vezes resultam em dados subestimados devido à omissão de informações por medo de ações punitivas. Desta forma, a confirmação por meio de análises toxicológicas em amostras biológicas se faz necessária. O mecônio, primeiras fezes do recém-nascido, tem sido proposto como matriz adequada para avaliação da exposição fetal, pois apresenta coleta não invasiva, fácil obtenção e fornece informações de longo prazo (2º e 3º trimestre de gestação). Entretanto, é uma matriz complexa, exigindo diversas etapas de purificação para posterior análise. No presente trabalho, métodos analíticos foram desenvolvidos visando à detecção dos biomarcadores da exposição fetal à cocaína e ao tetraidrocanabinol em amostras de mecônio por cromatografia gasosa acoplada à espectrometria de massas (GC-MS). Para ambos os métodos, a extração acelerada por solvente (ASE) foi utilizada para o isolamento dos analitos de interesse de amostras de mecônio, já que esta apresenta vantagens frente às técnicas convencionais, devido sua maior eficiência e menor manipulação da amostra. Associada à ASE, a extração em fase sólida (SPE) foi empregada para purificação e concentração dos analitos de interesse. Na etapa de desenvolvimento, inicialmente foram estabelecidos os procedimentos de derivatização e as condições cromatográficas a serem empregadas nas análises. Posteriormente, realizou-se a otimização dos procedimentos empregados na ASE, através de análise de superfície de resposta. Os métodos foram validados de acordo com o preconizado por referências internacionais, estabelecendo-se os limites de detecção e quantificação, recuperação, linearidade, precisão intra e interensaio e exatidão. O método para detecção dos biomarcadores da cocaína foi aplicado em 342 amostras de mecônio, provenientes do Hospital Universitário da Universidade de São Paulo (HU-USP). Destas, 19 (5,6%) apresentaram resultado positivo para um ou mais biomarcadores da exposição fetal à cocaína. Além disto, foi observada redução estatisticamente significante do peso ao nascimento, comprimento e perímetro cefálico entre os recém-nascidos expostos à cocaína durante a gestação. O método para a detecção da exposição fetal ao tetraidrocanabinol foi aplicado em 6 amostras positivas, obtidas do HU-USP, mostrando a aplicabilidade da técnica desenvolvida. / The use of illicit drugs is a relevant public health problem in the world. In Brazil, the number of women users in fertile age is increasing, which leads to a growing concern regarding fetal drug exposure. Adverse outcomes such as low birth weight, intra-uterine growth restriction, preterm birth, neurobehavioral and developmental deficits are associated with cocaine and cannabis use during pregnancy. Consequently, it would be important to obtain data related to drug misuse during gestation with the aim to plan medical and psychological interventions. Self-report drug use by pregnant women is often inaccurate due to feelings of guilt or fear of punitive actions. Therefore, confirmation by toxicological analysis in biological matrices must be accomplished. Meconium, the first stool of the newborn, has been proposed as a proper matrix to evaluate fetal exposure because it is collected by an easy and non-invasive way and enables the achievement of long-term information regarding fetal exposure. However, meconium is a complex matrix, which requires extensive sample cleaning previously to the analytes identification. In the present research, analytical methods were developed aiming the determination of cocaine and tetrahydrocannabinol biomarkers in meconium samples through gas chromatography-mass spectrometry (GC-MS). Accelerated solvent extraction (ASE) was used for analytes isolation due to its advantages over conventional techniques, such as greater extraction efficiency and minor sample handling. In order to achieve proper analytes selectivity and detectability, solid phase extraction (SPE) was employed for post-extraction clean-up. Initially, the derivatization procedure and chromatographic parameters were established for the development of the methods. Afterwards, ASE procedure was optimized through response surface methodology. The analytical methods were validated in accordance to international references. Limits of detection and quantification, recovery, linearity, precision and accuracy were obtained. The developed method for cocaine was applied in 342 meconium samples collected from the University Hospital of University of São Paulo (HU-USP). Among them, 19 (5.6%) showed positivity result for cocaine biomarkers. Additionally, newborns from mothers exposed to cocaine exhibited statistical significant lower birth weight, length and head circumference when compared with newborns from non-consumer mothers. For the method of tetrahydrocannabinol, applicability and importance was demonstrated by analyzing 6 positive samples from HU-USP.

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