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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.
151

Análise de efedrinas e anfetamina em urina empregando spe e spme por cg/em/em / Analysis of ephedrines and amphetamine in urine using spe and spme by gc/ms/ms

Sebben, Viviane Cristina January 2007 (has links)
O Brasil ocupa posição de destaque no consumo mundial de anfetaminas, contrariamente à tendência mundial de retração. Devido aos efeitos colaterais e ao alto potencial de abuso, a produção e comercialização de anfetaminas vêm sendo controladas no mundo inteiro. Com a restrição de uso, houve um retorno a procura pelos equivalentes naturais, especialmente as efedrinas presentes em diversas especialidades farmacêuticas, utilizadas no tratamento de doenças respiratórias. São componentes de vários compostos emagrecedores, suplementos alimentares e dietéticos utilizados para perda de peso e ganho de massa muscular. Face ao uso indiscriminado e a grande incidência de resultados falso-positivos nos testes de triagem para anfetaminas por imunoensaio enzimático homogêneo, fazem-se necessários testes confirmatórios. Neste sentido, este trabalho se propôs a desenvolver um método confirmatório simples e rápido para detecção, identificação e quantificação de efedrinas (efedrina/pseudoefedrina) em amostras de urina por por cromatografia a gás / espectrometria de massas-massas (CG/EM/EM), passível de ser adotado na rotina de laboratórios de análises toxicológicas. Devido à complexidade da matriz e as peculiaridades do analito, inicialmente procedeu-se o estudo do tratamento da amostra, considerando as etapas de derivatização, extração, pré-concentração e purificação, de modo a fornecer um extrato límpido, livre de impurezas, interferentes e com melhor sensibilidade, linearidade e seletividade analítica. Os métodos de extração usados foram extração líquido-líquido (ELL), extração em fase sólida (SPE) e microextração em fase sólida (SPME). Os resultados indicaram que o reagente de derivatização ciclohexanona foi o que apresentou melhor desempenho, menor custo e promoveu maior seletividade dos diasterômeros EF/PEF em colunas normais de CG. Sendo que o método mais apropriado para a detecção e identificação de efedrinas/anfetamina por CG/EM é a SPME levando em consideração características como simplicidade, rapidez, custo, recuperação e ausência de interferentes. Entretanto, considera-se valido o uso de SPE para a quantificação, devido à possibilidade de pré-concentração do analito. / Brazil is one of the biggest amphetamine consumers in the world, going against the worldwide retraction tendency. Due to serious adverse effects and high abuse potential, the production and commercialization of amphetamines has been controlled around the world. With the restriction of its use, there was a return in the search of natural equivalents, especially the ephedrines found in many medicines utilized in the treatment of respiratory diseases. Furthermore, they are components of dietary supplements used to lose weight and muscular mass gain. Because of the indiscriminate use and the high incidence of false-positive results in the amphetamines screening tests by enzyme immunoassay technique, it is necessary confirmatory tests. In this way, the aim of this work is to develop a confirmatory simple and quickly method for the detection and quantification of ephedrines (ephedrine and pseudoephedrine) gas chromatography / mass-mass spectrometry (GC/MS/MS), with possibility to be adopted in toxicological analyses laboratorial routine. Due to the complexity of the matrix and analyte peculiarities, initially proceeds the study of sample treatment, considering the derivatization, extraction, pre-concentration and purification steps, obtaining a limpidous extract, free of impurities, interferents and with better sensitivity, linearity and analytical selectivity. The extraction method used were liquid-liquid extraction (LLE), solid-phase extraction (SPE) and solid-phase microextraction (SPME). The results indicate that cyclohexanone was the derivatization agent with the best performance, lower price and good selectivity in diasteromers EF/PEF separation in normal GC columns. The most appropriate method for detection and identification of ephedrines/amphetamine by GC/MS is SPME, considering characteristics as simplicity, speed, cost, recovery and absence of interferents. However, the use of SPE must be considered to quantification, since it allowed analyte pre-concentration.
152

Análise de efedrinas e anfetamina em urina empregando spe e spme por cg/em/em / Analysis of ephedrines and amphetamine in urine using spe and spme by gc/ms/ms

Sebben, Viviane Cristina January 2007 (has links)
O Brasil ocupa posição de destaque no consumo mundial de anfetaminas, contrariamente à tendência mundial de retração. Devido aos efeitos colaterais e ao alto potencial de abuso, a produção e comercialização de anfetaminas vêm sendo controladas no mundo inteiro. Com a restrição de uso, houve um retorno a procura pelos equivalentes naturais, especialmente as efedrinas presentes em diversas especialidades farmacêuticas, utilizadas no tratamento de doenças respiratórias. São componentes de vários compostos emagrecedores, suplementos alimentares e dietéticos utilizados para perda de peso e ganho de massa muscular. Face ao uso indiscriminado e a grande incidência de resultados falso-positivos nos testes de triagem para anfetaminas por imunoensaio enzimático homogêneo, fazem-se necessários testes confirmatórios. Neste sentido, este trabalho se propôs a desenvolver um método confirmatório simples e rápido para detecção, identificação e quantificação de efedrinas (efedrina/pseudoefedrina) em amostras de urina por por cromatografia a gás / espectrometria de massas-massas (CG/EM/EM), passível de ser adotado na rotina de laboratórios de análises toxicológicas. Devido à complexidade da matriz e as peculiaridades do analito, inicialmente procedeu-se o estudo do tratamento da amostra, considerando as etapas de derivatização, extração, pré-concentração e purificação, de modo a fornecer um extrato límpido, livre de impurezas, interferentes e com melhor sensibilidade, linearidade e seletividade analítica. Os métodos de extração usados foram extração líquido-líquido (ELL), extração em fase sólida (SPE) e microextração em fase sólida (SPME). Os resultados indicaram que o reagente de derivatização ciclohexanona foi o que apresentou melhor desempenho, menor custo e promoveu maior seletividade dos diasterômeros EF/PEF em colunas normais de CG. Sendo que o método mais apropriado para a detecção e identificação de efedrinas/anfetamina por CG/EM é a SPME levando em consideração características como simplicidade, rapidez, custo, recuperação e ausência de interferentes. Entretanto, considera-se valido o uso de SPE para a quantificação, devido à possibilidade de pré-concentração do analito. / Brazil is one of the biggest amphetamine consumers in the world, going against the worldwide retraction tendency. Due to serious adverse effects and high abuse potential, the production and commercialization of amphetamines has been controlled around the world. With the restriction of its use, there was a return in the search of natural equivalents, especially the ephedrines found in many medicines utilized in the treatment of respiratory diseases. Furthermore, they are components of dietary supplements used to lose weight and muscular mass gain. Because of the indiscriminate use and the high incidence of false-positive results in the amphetamines screening tests by enzyme immunoassay technique, it is necessary confirmatory tests. In this way, the aim of this work is to develop a confirmatory simple and quickly method for the detection and quantification of ephedrines (ephedrine and pseudoephedrine) gas chromatography / mass-mass spectrometry (GC/MS/MS), with possibility to be adopted in toxicological analyses laboratorial routine. Due to the complexity of the matrix and analyte peculiarities, initially proceeds the study of sample treatment, considering the derivatization, extraction, pre-concentration and purification steps, obtaining a limpidous extract, free of impurities, interferents and with better sensitivity, linearity and analytical selectivity. The extraction method used were liquid-liquid extraction (LLE), solid-phase extraction (SPE) and solid-phase microextraction (SPME). The results indicate that cyclohexanone was the derivatization agent with the best performance, lower price and good selectivity in diasteromers EF/PEF separation in normal GC columns. The most appropriate method for detection and identification of ephedrines/amphetamine by GC/MS is SPME, considering characteristics as simplicity, speed, cost, recovery and absence of interferents. However, the use of SPE must be considered to quantification, since it allowed analyte pre-concentration.
153

Análise de efedrinas e anfetamina em urina empregando spe e spme por cg/em/em / Analysis of ephedrines and amphetamine in urine using spe and spme by gc/ms/ms

Sebben, Viviane Cristina January 2007 (has links)
O Brasil ocupa posição de destaque no consumo mundial de anfetaminas, contrariamente à tendência mundial de retração. Devido aos efeitos colaterais e ao alto potencial de abuso, a produção e comercialização de anfetaminas vêm sendo controladas no mundo inteiro. Com a restrição de uso, houve um retorno a procura pelos equivalentes naturais, especialmente as efedrinas presentes em diversas especialidades farmacêuticas, utilizadas no tratamento de doenças respiratórias. São componentes de vários compostos emagrecedores, suplementos alimentares e dietéticos utilizados para perda de peso e ganho de massa muscular. Face ao uso indiscriminado e a grande incidência de resultados falso-positivos nos testes de triagem para anfetaminas por imunoensaio enzimático homogêneo, fazem-se necessários testes confirmatórios. Neste sentido, este trabalho se propôs a desenvolver um método confirmatório simples e rápido para detecção, identificação e quantificação de efedrinas (efedrina/pseudoefedrina) em amostras de urina por por cromatografia a gás / espectrometria de massas-massas (CG/EM/EM), passível de ser adotado na rotina de laboratórios de análises toxicológicas. Devido à complexidade da matriz e as peculiaridades do analito, inicialmente procedeu-se o estudo do tratamento da amostra, considerando as etapas de derivatização, extração, pré-concentração e purificação, de modo a fornecer um extrato límpido, livre de impurezas, interferentes e com melhor sensibilidade, linearidade e seletividade analítica. Os métodos de extração usados foram extração líquido-líquido (ELL), extração em fase sólida (SPE) e microextração em fase sólida (SPME). Os resultados indicaram que o reagente de derivatização ciclohexanona foi o que apresentou melhor desempenho, menor custo e promoveu maior seletividade dos diasterômeros EF/PEF em colunas normais de CG. Sendo que o método mais apropriado para a detecção e identificação de efedrinas/anfetamina por CG/EM é a SPME levando em consideração características como simplicidade, rapidez, custo, recuperação e ausência de interferentes. Entretanto, considera-se valido o uso de SPE para a quantificação, devido à possibilidade de pré-concentração do analito. / Brazil is one of the biggest amphetamine consumers in the world, going against the worldwide retraction tendency. Due to serious adverse effects and high abuse potential, the production and commercialization of amphetamines has been controlled around the world. With the restriction of its use, there was a return in the search of natural equivalents, especially the ephedrines found in many medicines utilized in the treatment of respiratory diseases. Furthermore, they are components of dietary supplements used to lose weight and muscular mass gain. Because of the indiscriminate use and the high incidence of false-positive results in the amphetamines screening tests by enzyme immunoassay technique, it is necessary confirmatory tests. In this way, the aim of this work is to develop a confirmatory simple and quickly method for the detection and quantification of ephedrines (ephedrine and pseudoephedrine) gas chromatography / mass-mass spectrometry (GC/MS/MS), with possibility to be adopted in toxicological analyses laboratorial routine. Due to the complexity of the matrix and analyte peculiarities, initially proceeds the study of sample treatment, considering the derivatization, extraction, pre-concentration and purification steps, obtaining a limpidous extract, free of impurities, interferents and with better sensitivity, linearity and analytical selectivity. The extraction method used were liquid-liquid extraction (LLE), solid-phase extraction (SPE) and solid-phase microextraction (SPME). The results indicate that cyclohexanone was the derivatization agent with the best performance, lower price and good selectivity in diasteromers EF/PEF separation in normal GC columns. The most appropriate method for detection and identification of ephedrines/amphetamine by GC/MS is SPME, considering characteristics as simplicity, speed, cost, recovery and absence of interferents. However, the use of SPE must be considered to quantification, since it allowed analyte pre-concentration.
154

INFLUÊNCIA DO MANUSEIO NEONATAL SOBRE A PREFERÊNCIA DE RATOS JOVENS POR DROGAS PSICOESTIMULANTES / INFLUENCE OF NEONATAL HANDLING ON THE PREFERENCE OF YOUNG RATS FOR PSYCHOSTIMULANT DRUGS

Antoniazzi, Caren Tatiane de David 02 July 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The abusive use of psychostimulant drugs is a common social problem in countries of different cultures, whose incidence is increasing and alarming dimensions taken. Experimentally, some studies have shown the influence of early exposure to stress on changes in patterns of abuse, which may play an important role on the vulnerability to excessive use of psychostimulant drugs in adulthood. On the other hand, procedures such as neonatal tactile stimulation (TS) and neonatal isolation (NI), has been described by interfering with behavioral and neurophysiological parameters, which may persist into adulthood. This study aimed to investigate the conditioned place preference (CPP) and the psychostimulant drugs on anxiety-like symptoms related to abstinence in young rats exposed to TS and NI. In the first experiment, male pups of Wistar rats were subjected daily to TS or NI10 for 10 minutes, or NI60 for 1 hour, from postnatal day 1 (PND1) to PND21. The unhandled (UH) animals remained in the nest without any manipulation. At PND41, animals were subjected to CPP protocol induced by cocaine (20mg/kg, i.p.), for 10 days. At PND53, animals were tested for preference, and at PND55 symptoms of anxiety were evaluated on the elevated plus-maze task (EPM). TS and NI10 groups did not show preference on CPP, however UH and NI60 preferred the chamber associated with drug. In relation to anxiety-like symptoms observed during drug withdrawal, TS and NI10 groups presented higher time spent in the open arms of EPM, showing less anxiety-like behavior. Following the first study, a 2nd experiment was conducted to verify the influence of TS and NI on the CPP induced by amphetamine (AMPH), following the same neonatal handling protocol described in the previous experiment until the PND40, when animals were submitted to a CPP paradigm associated with administration of AMPH (4mg/kg, i.p.) for 8 days. At PND50, following behavioral assessment was observed that NI group had preference for the compartment associated with AMPH, and at PND53 during withdrawal of drug, TS group showed lower preference to compartment associated with drug. The exploratory activity in open field was higher in TS group at PND50, while NI group showed anxiety-like symptoms at PND53. Similarly, animals exposed to TS showed lesser degree of anxiety-like behavior in many different parameters evaluated at EPM and at staircase test, where the exploratory activity also was higher than other handlings. Taken together, these studies showed for the first time that beneficial effects of TS can modify the behavior on CPP paradigm, and influence the anxiety-like symptoms related to withdrawal from cocaine and AMPH. Continuity of studies related to the benefits of TS on reward pathways, neurotransmitter systems and signaling pathways, should be completed in the near future. / O uso abusivo de drogas psicoestimulantes é um problema social comum em países de diferentes culturas, cuja incidência tem tomado dimensões crescentes e alarmantes. Experimentalmente, alguns estudos tem mostrado a influência da exposição precoce ao estresse sobre alterações nos padrões de abuso, a qual pode cumprir um importante papel sobre a vulnerabilidade para o uso excessivo de drogas psicoestimulantes na idade adulta. Por outro lado, procedimentos como estimulação tátil (ET) neonatal e o isolamento neonatal (IN), têm sido descritos por interferir em parâmetros comportamentais e neurofisiológicos, que podem persistir durante a vida adulta. Assim, este estudo objetivou investigar a preferência condicionada de lugar (PCL) a drogas psicoestimulantes e sobre sintomas de ansiedade relacionados à abstinência, em ratos jovens expostos à ET e ao IN. No 1º experimento, filhotes machos de ratos Wistar foram submetidos diariamente à ET ou IN10, por 10 minutos, ou a IN60, por 1 hora, desde o dia pós-natal 1 (DPN1) até o DPN21. Os animais não manuseados (NM) permaneceram no ninho sem qualquer tipo de manipulação. No DPN40, os animais foram submetidos ao protocolo de PCL, induzido por cocaína (20mg/Kg, i.p.), durante 10 dias. No DPN52, os animais foram testados quanto à preferência e no DPN55 foram avaliados sintomas de ansiedade no teste do labirinto em cruz elevado (LCE). Os grupos ET e IN10 não apresentaram PCL, entretanto NM e IN60 preferiram o compartimento associado à droga. Em relação aos sintomas de ansiedade observados durante a abstinência da droga, os grupos ET e IN10, apresentaram maior tempo de permanência nos braços abertos do LCE, mostrando menor grau de ansiedade. Na sequencia do estudo, um 2º experimento foi conduzido, a fim de verificar a influência da ET e do IN sobre a PCL induzida por anfetamina (ANF), seguindo o mesmo protocolo de manuseio descrito no experimento anterior até o DPN40, quando os animais foram submetidos ao protocolo de PCL associado à administração de ANF (4mg/Kg, i.p.), durante 8 dias. No DPN50, após avaliação comportamental, observou-se que o grupo IN apresentou preferência pelo compartimento associado à ANF e no DPN53, durante abstinência da droga, o grupo ET apresentou menor preferência ao compartimento associado à droga. A atividade exploratória em campo aberto foi maior para o grupo ET no DPN50, enquanto o grupo IN apresentou sintomas de ansiedade no DPN53. De forma semelhante, animais expostos à ET mostraram menor grau de ansiedade em diversos parâmetros avaliados no LCE e no teste da escada, onde a atividade exploratória também foi maior do que para outros manuseios. Tomados em conjunto, estes estudos mostraram pela primeira vez que os efeitos benéficos da ET, podem modificar o comportamento frente à PCL, bem como influenciar os sintomas de ansiedade relacionados à abstinência de cocaína e ANF. A continuidade dos estudos relacionados aos benefícios da ET sobre vias de recompensa, sistemas de neurotransmissores e vias de sinalização celular, deverá ser realizada em um futuro breve.
155

Neonatal Quinpirole Treatment Enhances Locomotor Activation and Dopamine Release in the Nucleus Accumbens Core in Response to Amphetamine Treatment in Adulthood

Cope, Zackary A., Huggins, Kimberly N., Sheppard, A. Brianna, Noel, Daniel M., Roane, David S., Brown, Russell W. 01 April 2010 (has links)
Neonatal quinpirole treatment to rats produces long-term increases in D(2) receptor sensitivity that persists throughout the animal's lifetime, a phenomenon referred to as D(2) priming. Male and female Sprague-dawley rats were administered quinpirole (1 mg kg(-1)) or saline from postnatal days (P)1-11. At P60, all animals were given an injection of quinpirole (100 microg kg(-1)), and results showed that rats neonatally treated with quinpirole demonstrated enhanced yawning in response to quinprole, verifying D(2) receptor priming because yawning is a D(2) receptor mediated event. Beginning 1-3 days later, locomotor sensitization was tested through administration of d-amphetamine (1 mg kg(-1)) or saline every other day over 14 days, and horizontal activity and turning behavior were analyzed. Findings indicated that D(2)-priming enhanced horizontal activity in response to amphetamine in females compared to males at Days 1 and 4 of locomotor sensitization testing, and D(2)-priming enhanced turning in response to amphetamine. Seven to ten days after sensitization was complete, microdialysis of the NAcc core was performed using a cumulative dosing regimen of amphetamine (0.1-3.0 mg kg(-1)). D(2)-primed rats administered amphetamine demonstrated a 500% increase in accumbal DA overflow compared to control rats administered amphetamine. Additionally, amphetamine produced a significant increase in NE overflow compared to controls, but this was unaffected by D(2) priming. These results indicate that D(2) receptor priming as is produced by neonatal quinpirole treatment robustly enhances behavioral activation and accumbal DA overflow in response to amphetamine, which may underlie increases in psychostimulant use and abuse within the psychotic population where increased D(2) receptor sensitivity is a hallmark.
156

Sex Differences in Nicotine Sensitization and Conditioned Hyperactivity in Adolescent Rats Neonatally Treated with Quinpirole: Role of D2 and D3 Receptor Subtypes

Sheppard, Brianna, Lehmann, Julia, Cope, Zackary A., Brown, Russell W. 01 December 2009 (has links)
Neonatal quinpirole treatment in rats produces increased sensitivity of dopamine D2-like receptors throughout the animal's lifetime, referred to D2 priming. There is little information on the effects of nicotine in adolescent rats, especially in a model that has clinical relevance to psychosis where increased D2 receptor sensitivity is common. Male and female rats were treated with quinpirole (1 mg/kg) or saline from postnatal (P) day P21, given nicotine (0.5 mg/kg) or saline from P33 through P49, and placed into a locomotor arena for behavioral testing. Nicotine or saline treatment was preceded by the D2-like receptor antagonist eticlopride, D3 antagonist nafadotride, or saline. Conditioned hyperactivity was analyzed on P50 in the same context in a drug-free test. In females, D2 priming increased the locomotor response to acute nicotine, but did not affect subsequent nicotine sensitization, and only non–D2-primed females demonstrated conditioned hyperactivity. Eticlopride and nafadotride blocked behavioral sensitization, although nafadotride was more effective at blocking nicotine-conditioned hyperactivity in females. In males, D₂ priming enhanced sensitization to nicotine and produced conditioned hyperactivity, which were blocked by eticlopride and nafadotride. These results have implications for psychosis and comorbidity of nicotine abuse in adolescence.
157

Preclinical evaluation of a potential treatment for ADHD targeting the serotonin 1B receptor subtype

Saber, Yasir Hazim January 2019 (has links)
No description available.
158

Altered States of Style: The Drug-Induced Development of Jack Kerouac's Spontaneous Prose

Izant, Eric M. 04 December 2008 (has links) (PDF)
Jack Kerouac's spontaneous prose method was inspired in part by his use of drugs while writing. While there is abundant biographical evidence that Kerouac used drugs frequently, little attention has been paid to their effects on the development of his style. This thesis attempts to demonstrate that the altered states of consciousness produced by Kerouac's drug use should be considered in conjunction with historical, cultural, and biographical forces in tracing the evolution of Kerouac's creative growth. As a member of the Beat Generation, Kerouac used drugs both as a social statement of rebellion and for artistic insight. In fact, he consciously entered into a well-established tradition of writers looking to drugs as modern-day muses. Within this legacy, drugs were commonly viewed as chemical gateways to a transcendental realm of visionary truth that the artists could enter and return with, thus becoming a literary seer. Kerouac, who believed that the ossification of standardized written English into rigid forms of grammar and sentence construction curtailed its potential for complete communication, sought a prose style that would allow for a maximum of authenticity and fidelity to organic thought with a minimum of revision. Kerouac used drugs like amphetamine, marijuana, and alcohol, each of which offered unique modes of perception, to enter into new frameworks of consciousness, and then recreated these altered states in writing. These three substances—amphetamine, marijuana, and alcohol—served as the basis in the development of Kerouac's style. Amphetamine, in the form of the over-the-counter drug Benzedrine, gave Kerouac the energy for his legendary typing marathons, allowing him to write On the Road in three weeks and The Subterraneans in three days. While writing On the Road in particular, Kerouac began formulating the stylistic approach that he subsequently dubbed "spontaneous prose." Its basic tenants, including a de-emphasis on revision, limited punctuation, and long sentences, were encouraged by Benzedrine's stimulant properties, which tended to focus Kerouac's attention on the exterior world of events, temporality, and movement. His amphetamine-induced texts attempt to communicate accurately by confessing the minutia of surface details. Kerouac's spontaneous style, however, soon evolved into the "sketching" technique seen in Visions of Cody and Dr. Sax, partially as a result of his marijuana-induced desire to share subjective perceptions truthfully. Rather than focusing on the exterior world, the marijuana texts look inward for authenticity. Marijuana helped Kerouac facilitate this inner orientation by its pharmacodynamic tendency to induce dream-like, associative states; when reproduced textually, these impressions seemed to resemble the unconscious structures of Kerouac's mind, which he shared hoping for complete communication via the universality of shared experience. Kerouac used both the amphetamine and marijuana modes to varying degrees and interchangeably for most of his career, and with the first section of Desolation Angels, written in sobriety, achieved their greatest synthesis, demonstrating that drugs were not the props to his style, but rather the impetus—even in the absence of drugs, Kerouac's prose retained its own essential, idiosyncratic features. Finally, in the latter part of Kerouac's career, alcohol proved that drugs could also negatively affect his style, as shown in Big Sur and Vanity of Duluoz. Their return to a plainer prose—some would say poorer prose—was no doubt the result of rampant alcohol abuse, and the unfortunate end to Kerouac's life and writing.
159

Biosensor based on immobilized amine transaminase for detection of amphetamine

Öh, Clara January 2020 (has links)
Amine transaminases (ATA) catalyse the transfer of an amino group from one molecule and replaces a ketone or aldehyde with the amino group, the amino group on the amino-donor is replaced with a ketone or aldehyde. This enzyme, ATA from Chromobacterium violaceum, has previously been used to catalyse the reaction involving amphetamine, therefore, it might be possible to use this enzyme to convert amphetamine and the product absorbs in the UV spectrum and can therefore be measured spectrophotometrically. The aim of the project was to explore the possibility of using ATA in a portable biosensor for the detection of amphetamine. A literature study of commercially available portable biosensors was performed, activity of the free enzyme was tested against two substrates, methylbenzylamine (MBA) and amphetamine. Research on immobilization techniques, materials, and surface functionalization was done to chose suitable methods for immobilizing ATA. Two immobilization methods were suggested and one of the methods, ionic immobilization through His-tag towards Ni2+ on the surface, was tested for enzyme activity toward MBA. The enzyme activity of the free enzyme in solution towards MBA was comparable to previously reported enzyme activity, however, no enzyme activity towards amphetamine was observed. No activity was observed for the immobilized enzyme, but it might be due to the experimental design, more experiments need to be performed to draw conclusions. / Amintransaminaser (ATA) katalyserar överförandet av en amingrupp från en molekyl och ersätter en keton eller aldehyd med den amingruppen, amingruppen på amin-donatorn ersätts med en keton eller aldehyd. Det här enzymet, ATA från Chromobacterium violaceum (CvATA), har tidigare använts för att katalysera en reaktion som involverar amfetamin, därför skulle detta enzym kunna användas på amfetamin. Produkten av reaktionen absorberar i UV spektrumet och kan mätas med en spektrofotometer. Målet med projektet var att utforska möjligheten av att använda CvATA i en biosensor för att detektera amfetamin. En litteraturstudie på kommersiellt tillgängliga bärbara biosensorer genomfördes, aktiviteten av det fria enzymet testades mot två substrat, metylbenzylamin (MBA) och amfetamin. Information samlades om immobiliseringstekniker, material, och ytfunktionalisering gjordes för att välja ut lämpliga metoder för immobilisering av CvATA. Två immobiliseringsmetoder föreslogs och en av metoderna, immobilisering via enzymets His6-tagg och Ni2+ joner på ytan, testades för enzymaktivitet mot MBA. Enzymaktiviteten av det fria enzymet i lösning mot MBA var i samma storleksordning som tidigare rapporterad enzymaktivitet, men ingen enzymaktivitet mot amfetamin kunde observeras. Ingen aktivitet kunde observeras för det immobiliserade enzymet, men det kan vara på grund av designen på experimentet, fler experiment behöver göras för att kunna dra några fler slutsatser.
160

Characterization of Locomotor Response to Psychostimulants in the Parthenogenetic Marbled Crayfish (<i>Procambarus fallax</i> forma <i>virginalis</i>): A Promising Model for Studying the Epigenetics of Addiction

Jackson, Cedric James, Jackson 15 July 2016 (has links)
No description available.

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