A 3,4-metilenodioximetanfetamina (MDMA) é a principal substância psicoativa comercializada ilegalmente em comprimidos de ecstasy. O MDMA é uma droga de ação psicotrópica e uso proscrito, conforme lista F (grupo F2) da ANVISA, pois apresenta propriedades alucinógenas e estimulantes e seu uso/abuso pode gerar uma série de danos à saúde dos usuários. O desenvolvimento de eletrodos quimicamente modificados (EQMs) na eletroanalítica tem por finalidade a obtenção de sistemas de detecção mais sensíveis e seletivos para o analito de interesse. Também, considera-se necessário desenvolver novas técnicas e métodos para a detecção de compostos em amostras de interesse forense, a fim de obter ferramentas para auxiliar os cientistas forenses no combate ao comércio ilícito de substâncias. Conforme problemática exposta, este trabalho teve por finalidade o desenvolvimento de eletrodos quimicamente modificados utilizando como modificadores da superfície eletródica de carbono vítreo o Nafion e Nafion/CB[7], utilizando deposição por drop coating e spin coating para a detecção de MDMA através das técnicas de voltametria cíclica e onda quadrada. Conforme o sistema empregado, os melhores EQMs desenvolvidos foram de Nafion (1,5% v/v) e Nafion (1,5% v/v)/CB[7] (10,0 µg.mL-1). Os EQMs desenvolvidos apresentaram limite de detecção e quantificação na faixa de traços e menores que aqueles reportados em outros trabalhos da literatura. Considerando a aplicação dos EQMs para a detecção de MDMA em amostras de ecstasy, verificaram-se as respostas voltamétricas de outras substâncias: cafeína, metanfetamina, teobromina, lidocaína, cloridrato de procaína, (±)-metanfetamina e cloridrato de cocaína. Nas condições experimentais empregadas, observou-se que as substâncias estudadas não atuam como falsos positivos para o MDMA. Paralelamente, obtiveram-se onze lotes de comprimidos de ecstasy (apreendidos e cedidos pela Polícia técnico-científica de Ribeirão Preto-SP) e realizaram-se análises qualitativas e quantitativas nos mesmos, utilizando técnicas colorimétricas (Marquis, Ácido sulfúrico, Simon e Simon com acetona) e cromatográficas (CG-EM E CLAE-EM). Considerando o melhor EQM desenvolvido, quantificaram-se 11 lotes de ecstasy pela técnica voltamétrica e cromatográfica, dentre os lotes estudados, dois não continham MDMA, um apresentou uma mistura de MDMA e cafeína e os demais continham MDMA. A concentração de MDMA presente nos lotes variou de 0 até 61 % em massa. A detecção de MDMA em ecstasy pelo método voltamétrico desenvolvido se mostrou viável e sensível para o analito de interesse. / The 3,4-methylenedioxymethamphetamine (MDMA) is the main psychoactive component of ecstasy tablets, that have an illicit trade. MDMA has been an illicit psychotropic drug, and it has a prohibited use (group F2, in ANVISAs F list), because of its hallucinogenic and stimulating effects, and the use/abuse can poses serials health risks. The development of chemically modified electrodes (CME) in electroanalytical methods aims to get more sensitive and selective systems to detect the analytes. In this context, it is necessary to develop new techniques and methodologies to the detection of illicit samples; it provides more tools to help the forensic scientists to combat the illicit drug trade. So, this work focused in the development of chemically modified electrodes (CMEs) with modifications on the glassy carbon surface by drop coating and spin coating using Nafion and Nafion/CB[7] solutions. The CMEs were tested using cyclic, and square wave voltammetry to detect MDMA. Considering the employed system, the best CMEs were made by Nafion (1.5% v/v), and Nafion (1.5% v/v)/CB[7] (10.0 µg.mL-1) thin films. It was possible to observe better sensitivities for these sensors, in comparison to other MDMA studies reported in the literature. The specificity of the proposed sensors was checked in relation to other drugs: caffeine, methamphetamine, theobromine, lidocaine, procaine hydrochloride, and cocaine hydrochloride. These drugs do not interfere in this voltammetric method. Additionally, we studied eleven lots of ecstasy samples, allowed by the Scientific Police - Ribeirão Preto-SP, and we provide qualitative and quantitative studies using colorimetric techniques (Marquis, Sulfuric acid, Simon, and Simon with acetone), and chromatografic techniques (GC-MS and HPLC-MS). The MDMA quantification in real samples was obtained by high performance liquid chromatography with a mass spectrophotometer, and we compared with the voltammetric technique, using the developed CME. Between the analyzed lots, two of them didnt present in their composition, one lot had a mix of caffeine and MDMA, and another presented MDMA. The MDMAs concentration in lots had a large variation, with 0 to 61 % w/w. The MDMAs voltammetric detection in ecstasy lots was viable. And, it is also possible to apply this methodology to analyze MDMA traces.

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.

A ciência forense moderna caminha lado a lado com a pesquisa científica. Os cientistas forenses se deparam diariamente com vários casos que requerem a análise de resíduos provenientes de disparos de arma de fogo (gunshot residues - GSR). Este trabalho contempla o desenvolvimento de uma metodologia para determinar assinaturas químicas de disparos de arma de fogo, medindo-se as concentrações de Pb, Ba e Sb presentes nos resíduos provenientes destes disparos depositados nas proximidades do orifício de entrada de projéteis, baseada na técnica de espectrometria de massas de alta resolução com fonte de plasma indutivamente acoplado (ICP-MS). Foram realizados disparos em cinco tipos de tecidos-alvos e coletados testemunhos em regiões próximas ao orifício de entrada dos projéteis. Os resultados demonstraram que o método possibilitou identificar e distinguir os resíduos de revólver calibre .38 ao de pistolas calibres .40 e 9 mm. O uso de gráficos ternários como ferramenta de análise dos dados coletados, permitiu identificar padrões específicos de distribuição de amostras em branco e dos resíduos depositados após disparos de revólveres e pistolas. A metodologia possibilitou a atribuição da origem dos disparos por meio de confirmação dos resíduos coletados também das mãos dos atiradores. Como conseqüência a metodologia representa um grande avanço nos procedimentos da polícia e visa adicionar uma contribuição valiosa às investigações forenses. / The modern forensic science goes hand in hand with scientific research. The forensic scientists are faced every day with many cases requiring the analysis of residues from firing gun (gunshot residues GSR). This works describes the development of a methodology to determine chemical signatures of shots from a firearm, by measuring the concentrations of Pb, Ba e Sb in the residues from these shots deposited near the entrance hole of bullets, based on the technique with high resolution inductively coupled plasma mass spectrometry (HRICP-MS). Shots were performed on five types of target-fabrics and collected testimonies from regions close to the entrance hole of projectiles. The results showed that the method enabled us to identify and distinguish the residues of the .38 caliber revolver and pistols .40 and 9mm caliber. The use of ternary graphs as a tool for data analysis helped to identify specific patterns of distribution of blank samples and gunshot residues deposited after firing revolvers and pistols. The methodology enabled the assignment of the origin of the shot through the confirmation of the residues collected also from the hands of shooters. As a result the methodology in police procedures and aims to add a valuable contribution to forensic investigations.

<p>Anabolic androgenic steroids are testosterone and its derivates. Testosterone is the most important naturally existing sex hormone for men and is used for its anabolic effects providing increased muscle mass. Testosterone is taken orally or by intramuscular injection in its ester form and are available illegally in different forms of esters. Anabolic androgenic steroids are today analyzed only in urine. To differentiate between the human natural testosterone and exogenous supply the quote natural testosterone and epitestosterone is used. Detection of testosterone esters in serum is an unmistakable proof of exogenous supply of testosterone. The aim of this thesis was to find a method for determining testosterone esters in serum and to study an extraction method possible for quantification of testosterone esters in serum.</p><p>The technique used to separate and identify the Testosterone esters was Liquid Chromatography Tandem Mass Spectrometry Electro Spray Ionisation. Parameters for chromatography and mass detection were optimized for nine testosterone esters and evaluated according to selectivity, resolution and intensity. A method that could be used for determination of testosterone esters in serum was found. The MS-method was set and at least three possible transitions for each testosterone ester were found. The best choice of column proved to be the C18 column where all the esters were separated and seven of them were base-line separated. The C18 column along with methanol and ammonium acetate buffer, 5 mM, pH 5 showed the highest sensitivity for Multiple Reaction Monitoring-detection. A gradient profile for a total runtime of 5.6 minutes was established. Two alternative extraction procedures were tested, with <em>tert</em>-butylmethylether or diethyl ether/ethyl acetate and both seemed to work satisfactory. Analysis of serum proved to work well and no severe interference occurred. Results from the linearity tests indicate that future quantification method in serum will be possible.</p>

Anabolic androgenic steroids are testosterone and its derivates. Testosterone is the most important naturally existing sex hormone for men and is used for its anabolic effects providing increased muscle mass. Testosterone is taken orally or by intramuscular injection in its ester form and are available illegally in different forms of esters. Anabolic androgenic steroids are today analyzed only in urine. To differentiate between the human natural testosterone and exogenous supply the quote natural testosterone and epitestosterone is used. Detection of testosterone esters in serum is an unmistakable proof of exogenous supply of testosterone. The aim of this thesis was to find a method for determining testosterone esters in serum and to study an extraction method possible for quantification of testosterone esters in serum. The technique used to separate and identify the Testosterone esters was Liquid Chromatography Tandem Mass Spectrometry Electro Spray Ionisation. Parameters for chromatography and mass detection were optimized for nine testosterone esters and evaluated according to selectivity, resolution and intensity. A method that could be used for determination of testosterone esters in serum was found. The MS-method was set and at least three possible transitions for each testosterone ester were found. The best choice of column proved to be the C18 column where all the esters were separated and seven of them were base-line separated. The C18 column along with methanol and ammonium acetate buffer, 5 mM, pH 5 showed the highest sensitivity for Multiple Reaction Monitoring-detection. A gradient profile for a total runtime of 5.6 minutes was established. Two alternative extraction procedures were tested, with tert-butylmethylether or diethyl ether/ethyl acetate and both seemed to work satisfactory. Analysis of serum proved to work well and no severe interference occurred. Results from the linearity tests indicate that future quantification method in serum will be possible.

There is an increase in bombing assaults in recent years in our country. Determining the explosive material used in these cases by the quick and correct analysis of the evidence obtained after the explosions, is an important starting point for the investigations which are done to reach the perpetrators. The forensic chemistry investigations have to be correct, exact and rapid in order to reach the right criminal. In this study, the Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Thermal Energy Analyser (GC-TEA) methods which are being used for the determination of the explosive materials&rsquo / residues used in bombing attacks are optimized with the standard solutions of 2,4,6-Trinitrotoluene (TNT) and 1,3,5-trinitro-1,3,5-triazocyclohexane (RDX) and standard mixture solution. The two methods were compared by analysing the postexplosion soil samples. Also an efficient and applicable sample preparation procedure was developed. The results showed that both methods are efficient and sensitive for the postexplosion investigations. It is seen that GC-TEA has lower detection limit and simple chromatograms due to its selectivity against only nitro group containing explosives. However it is concluded that there is a need for a reliable and sensitive method like GC-MS which provides identification and library search, for the determination of the organic components which can not be identified with GC-TEA

Narcotic and psychotropic substances are all chemicals that affect a person&rsquo / s mental activities, perceptual abilities, behavior and level of consciousness / they may cause physical and/or psychological dependence. For determination of narcotic and psychotropic substances, chromatographic techniques are usually preferred which are aimed to identify the target chemicals and require several extraction steps. In this study, an Infrared Spectrometric method has been developed for qualitative determination of most widely encountered substances (morphine, heroin, cocaine, MDMA (3,4-methylenedioxymethamhetamine) and amphetamine) and additives (caffeine, paracetamol and lactose). Standard reference materials and illicit samples have been analyzed in powdered form by using Fourier Transform Infrared-Attenuated Total Reflectance (FTIR-ATR) technique. In the first part, a spectral FTIR database was constituted from the standard references. Illicit samples containing drugs and additives in varying percentages were analyzed using the same method and their database forecast results were compared with results from Gas Chromatography and High Pressure Liquid Chromatography. In the second part of the study, the possibility of finding a similarity between two samples just by comparing their spectra was investigated. For this purpose, all illicit sample spectra were collected in a new database, and then randomly selected samples were searched using this database. Most of the search attempts resulted in a correct match. Consequently, it has been observed that FTIR-ATR can be used as a priory detection step for classification studies / moreover with this technique pre-determination of narcotic and psychotropic substances can be done simply and rapidly.

A common practice amongst street drug manufacturers and dealers is to combine the illicit drug of abuse they intend to distribute with additional substances. Substances added in an attempt to mimic or enhance the desired effect of the drug of abuse are known as adulterants as opposed to diluents, which are added simply to increase the weight of the product. By definition, an adulterant has a physiological effect on the body and as physiologically active compounds these adulterants may have side effects apart from the drug it is added to. They can be minimal, treatable, or otherwise manageable while others can be worse than those incurred from the drug of abuse itself. Due to varying trends in street drug purity, an effort must be made to understand the effects adulterants and diluents, as well as mixtures thereof, may have on forensic drug analysis. Colorimetric spot test analysis is typically performed using a representative sample of the raw, suspected drug material. These tests are often employed in the lab prior to any attempt to isolate a specific compound or at the scene before an arrest is made. This being the case, the reagents will be exposed to and have the potential to react with anything present in the sample with the drug of abuse. While much work has been done regarding the specificity and cross reactivity of colorimetric spot tests, limited information is available about how mixtures of adulterants may affect the results. This research consists of two parts which approach the common theme of adulterants differently. The first part is a literature based investigation into the pathological side effects of several common drug adulterants. The specific compounds discussed are: levamisole, phenacetin, atropine, and several topical anesthetics (benzocaine, lidocaine, prilocaine, and procaine). A review of articles from the scientific literature was conducted in order to convey what is known in the medical field regarding the effects these compounds can have on the body. The second part of this research was a laboratory based investigation which analyzed the effects of twenty-three common adulterants on two colorimetric spot tests: the Marquis reagent for the presumptive identification of heroin, morphine, amphetamine, methamphetamine, and 3,4-methylenedioxy-N-methamphetamine (MDMA) and the modified Scott test for the presumptive identification of cocaine. This was performed in order to observe the reactivity of these compounds so that a better understanding of the effect their presence can have on the analysis of seized drug samples using these tests could be obtained. The literature review portion of this research revealed that the adulterants levamisole, atropine, phenacetin, and the topical anesthetic adulterants lidocaine, prilocaine, benzocaine, and procaine, can be toxic and have severe, deleterious effects on the body in both chronic and acute exposures. Levamisole stimulates the immune system resulting in the production of self-reactive antibodies that attack neutrophils. This causes an autoimmune disorder that weakens the immune system and causes leukocyte agglutination leading to necrotizing vasculitis. Atropine functions to decrease the parasympathetic tone and increase the sympathetic tone in the body. An overdose can cause anticholinergic toxicity, a syndrome very similar to sympathomimetic toxidrome caused by cocaine overdose. Both are characterized by hypertension, hyperthermia, tachycardia, ataxia, disorientation, and mydriasis. However, they can be distinguished as anticholinergic toxicity causes dry and flush skin and mydriasis which is unreactive to light while sympathomimetic toxidrome causes profuse sweating and mydriasis which is reactive to light. Phenacetin is metabolized to O-ethyl-N-acetyl-p-benzoquinone imine (O-Et-NAPQI), a highly reactive and unstable electrophile. It is capable of covalently binding with proteins and other cellular components, including deoxyribonucleic acid (DNA). This leads to mutagenesis and subsequent tumor generation as well as apoptosis and necrosis of various tissues in the bladder and kidneys. The topical anesthetics have each been associated with the development of methemoglobinemia. This is a condition caused by an increase in the concentration of methemoglobin in the blood. Methemoglobin binds more strongly to oxygen so that it cannot be released to the tissues resulting in oxygen starvation. This was found to be caused by the metabolism of prilocaine and lidocaine to the oxidative compounds O-toluidine and 2,6-xylidine respectively. The cause has not been previously reported for benzocaine or procaine. The laboratory portion of this research revealed the impact several adulterants and their mixtures can have on colorimetric spot tests. Testing with approximately 1 mg of sample material revealed that eight out of the twenty-three adulterants reacted with the Marquis reagent to cause a color change within 15 minutes. Of the ten 3-component mixtures tested, eight resulted in a color change. Of the six five-component mixtures, four resulted in a color change; of the six eight-component mixtures, three resulted in a color change; and of the six ten-component mixtures, five resulted in a color change. Of the color changes observed, none were consistent with the "expected" color change for a presumptively positive result of the Marquis test. Testing with the adulterant diphenhydramine revealed that this compound had a unique and intense reaction with the Marquis reagent. This compound initially reacted by turning the liquid a vibrant yellow-green upon contact with the sample. Prior to 2 minutes, solid red-brown aggregates formed in the liquid and proceeded to increase in size while the reagent solution darkened to a red-black color over the 15 minutes of observation. Mixtures containing diphenhydramine each reacted differently. Solid material did not form in the mixture tests and the color changes observed ranged from light orange to a dark red-orange. In addition, one 3-component mixture containing adulterants which did not cause a color change when tested individually (diltiazem, acetaminophen, and quinine) was observed to cause a light brown color to develop, which darkened over the 15 minutes of observation. The results for the modified Scott test showed that the complexity of this test has made it highly specific for cocaine. None of the individual components or mixtures tested reacted in a manner consistent with a presumptively positive identification for cocaine hydrochloride (HCl) or cocaine base for all three steps. Of the twenty-three adulterants tested, eight of the twenty-three gave a similar result to cocaine base in step 1, however, of these eight, only one (quinine) gave a similar result to cocaine base in step 2, and this adulterant did not react consistently to cocaine base in step 3. The research using the adulterant mixtures revealed that the compounds present in these samples tended to react individually with the modified Scott test reagents. In other words, the results for each mixture appeared as a combination of the individual results for each component. While the results observed for the adulterants and mixtures tested were not consistent with the expected presumptively positive results for the drugs these tests are used to detect, it was concluded that the presence of adulterants in a sample has the potential to affect the results of a colorimetric spot test in a variety of ways. Given that these tests are typically employed on samples of raw suspected drug material, it is important that analysts understand the impact adulterants can have on the interpretation of presumptive drug tests.

Orientador: Marcos Nogueira Eberlin / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-17T02:49:27Z (GMT). No. of bitstreams: 1 Romao_Wanderson_D.pdf: 8870695 bytes, checksum: 3c9e22c3de92cb5c092d522b9b0a9faf (MD5) Previous issue date: 2010 / Resumo: Embora seja um tema que desperte bastante interesse perante a sociedade científica, a aplicação da química no campo da criminalística ainda constitui uma nova linha de pesquisa no Brasil. Neste trabalho, o perfil químico de várias drogas de abuso (anfetaminas, piperazinas, cocaína e dietilamida do ácido lisérgico (LSD)), documentos e derivados de petróleo foram investigados. Para análise de drogas de abuso, a easy ambient sonic-spray ionization (EASI-MS) é uma poderosa ferramenta na caracterização de amostras na sua forma original, como é o caso de amostras de ecstasy e LSD, que são vendidos como comprimidos e selos, respectivamente. A espectrometria de massas foi utilizada também para estudar a mobilidade iônica de isômeros da clorofenilpiperazina (o-CPP, m-CPP e p-CPP), onde o m-CPP se enquadra na lista de substâncias proscritas. Foi também demonstrado que a cromatografia em camada delgada (CCD) continua sendo uma técnica confiável para a identificação do 3,4-metilenodimetoxianfetamina (MDMA) e outros adulterantes em comprimidos de ecstasy, mas ela pode fornecer resultados falso-negativos. A associação da CCD com EASI-MS potencializa a identificação de todas as anfetaminas que poderiam ser usadas na fabricação de drogas de rua, como o ecstasy. Uma importante ferramenta analítica para estudar os contaminantes inorgânicos em drogas de abuso é a técnica de fluorescência de raios-X. Perfis inorgânicos foram construídos para várias drogas de abuso. Esses dados, associados a ferramentas quimiométricas, permitem classificar drogas de abuso. Para análise de documentos, EASI-MS e Desorption electrospray ionization mass spectrometry (DESI-MS) podem ser usados como um método de fingerprints diretos, robuscos, não-destrutivos, rápidos e simples para a investigação da autenticidade do papel-moeda nacional e internacional. Uma nova metodologia foi desenvolvia para estudar derivados de petróleo: venture easy ambient sonic-spray ionization mass spectrometry, V-EASI-MS. A presença de uma série homólga abundante, como as alquil-piridinas, é um indicativo de uma amostra de gasolina comercial ser de boa qualidade. A presença de outras séries homólogas com maiores valores de DBE (número de insaturações e anéis) para a classe dos nitrogenados (Classe N), é um indicativo de que adulterantes como querosene e diesel foram adicionados na gasolina / Abstract: The application of chemical analysis in the criminalistic field is a subject has always atract academic interesty. However in Brazil, this research field is still incipient. In this thesys, the chemical profiles of several drugs of abuse (amphetamines, piperazines, cocaine and LSD), documents and crude oil derivatives (gasoline, kerosene and diesel) were studied. For the analyzes of the drugs, easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to provide a relatively simple and selective screening tool to characterize and identify samples in their native form, as exemplified for ecstasy and LSD samples, sold in tablet and blotter forms, respectively. Mass spectrometry has also allowed the study of the ionic mobility of isomers derived of chlorophenilpiperazine (o-CPP, m-CPP e p-CPP). Only the m-CPP isomer is reported in the Brazilian lists of proscribed drugs (F and F2 Lists). It was also demonstrated that thin layer chromatography (TLC), although non expensive, reliable and versatile, may lead to false positives results. EASIMS combined with TLC provided a powerful screening tool for the analysis of street drugs with fast and indisputable results. An important technique available for the analysis of inorganic contaminants in drugs of abuse is the X-ray fluorescence (XRF) technique. XRF has several advantageous features such as multielemental capability, good detectivity, high precision, short analytical times, and is nondestructive. These characteristics make XRF applicable to a great variety of samples, offering an efficient technique for metal determinations in drugs of abuse. In this work, XRF followed by chemometric treatment has been applied to classify drugs of abuse. For analyzes of documents and banknotes (Brazilian real, dollar, and euro bills), two desorption/ionization techniques (DESI-MS and EASI-MS) were used as proof-of-principle techniques and ambient mass spectrometry was shown to function as a direct, nearly instantaneous, reproducible, and non-destructive method for their chemical analysis. An innovative and recently-introduced technique, Venture Easy Ambient Sonic-Spray Ionization Mass Spectrometry (V-EASI-MS), was also applied for rapid and reliable typification of gasoline samples and adulteration by addition of diesel and kerosene. Without any extraction or pre-treatment procedures, samples of gasoline, kerosene, diesel, and admixtures of gasoline/diesel and gasoline/kerosene were directly analyzed by VEASI(+)- MS / Doutorado / Quimica Analitica / Doutor em Ciências

Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-05-16T15:19:56Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Pamela P. Nunes.pdf: 2080639 bytes, checksum: 7d94a40f060481c71126202ecd797dda (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-05-16T15:20:07Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Pamela P. Nunes.pdf: 2080639 bytes, checksum: 7d94a40f060481c71126202ecd797dda (MD5) / Made available in DSpace on 2018-05-16T15:20:20Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Pamela P. Nunes.pdf: 2080639 bytes, checksum: 7d94a40f060481c71126202ecd797dda (MD5) Previous issue date: 2017-12-06 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Despite advances in education, middle school classes, usually, are conducted with an excess of memorization and lack of meaning, in addition to the didactic potential of the experiments being poorly explored. The insertion of chemical concepts through contextualized approaches motivated the accomplishment of this work, which took into consideration the following question: How to approach scientific and meaningful knowledge in High School, using Forensic Chemistry in a contextualized way? In this sense, the study presents a proposal of learning through the forensic chemistry linked to the daily life of the student. In the mini-course format, we seek to investigate the learning of chemical concepts through forensic experiments in a third year high school class. The research conducted in a qualitative approach, was applied in the SESC José Roberto Tadros, western zone of Manaus-AM (Brazil). The participants were third year high school students and a chemistry teacher, having as instruments of data collection questionnaires and semi-structured interview. The analysis of the data was organized under the light of the Discursive Textual Analysis (DTA), proposed by Moraes and Galiazzi (2007). The results showed that students have difficulty in learning concepts, and that, through contextualized classes, there was more assimilation of chemical concepts by them. We believe that, by working with chemical concepts in parallel with the execution of thematic experiments, it is possible to promote Significant Learning, considering that all the experiments evaluated are perfectly consonant with the contents of High School. Therefore, with this study, it is hoped to promote the learning of students' concepts through thematic activities, such as Forensic Chemistry, in addition to enriching the learning of Chemistry. / Apesar dos avanços na Educação, comumente as aulas de Ensino Médio são conduzidas com um excesso de memorização e falta de significado, além do potencial didático dos experimentos ser deficientemente explorados. A inserção de conceitos químicos por meio de abordagens contextualizadas motivou a realização deste trabalho, que levou em consideração a seguinte questão: Como abordar conhecimento científico e significativo no Ensino Médio utilizando a Química Forense de maneira contextualizada? Neste sentido, o estudo apresenta uma proposta de aprendizagem por meio da química forense ligada ao cotidiano do aluno. No formato de minicurso, buscamos investigar a aprendizagem de conceitos químicos por meio dos experimentos forenses em uma turma de terceiro ano do Ensino Médio. A pesquisa, conduzida em uma abordagem qualitativa, foi aplicada no SESC José Roberto Tadros, Zona Oeste, Manaus-AM. Os participantes foram alunos do terceiro ano do Ensino Médio e um professor de química, tendo como instrumentos de coleta de dados questionários e entrevista semiestruturada. A análise dos dados foi organizada à luz da Análise Textual Discursiva (ATD), proposta por Moraes e Galiazzi (2007). Os resultados evidenciaram que os alunos têm dificuldades na aprendizagem de conceitos, e que, por meio de aulas contextualizadas, houve maior assimilação de conceitos químicos por eles. Acreditamos que trabalhando conceitos químicos em paralelo com a execução de experimentos temáticos é possível promover uma Aprendizagem Significativa, tendo em vista que todos os experimentos avaliados estão perfeitamente consonantes com o conteúdo de Ensino Médio. Portanto, com este estudo, espera-se promover a aprendizagem de conceitos dos alunos por meio de atividades temáticas, tais como Química Forense, além de enriquecer o aprendizado da Química.