Mestrado em Química
URI Permanente para esta coleção
Nível: Mestrado Acadêmico
Ano de início: 2006
Conceito atual na CAPES: 5
Ato normativo: Homologação da 85ª Reunião do CTC-ES, Parecer CNE/CES nº 163/2005.
Processo nº 23001.000081/2005-56 do Ministério da Educação.
Publicado no DOU 28/07/2005, seção 1, página 11)
Periodicidade de seleção: Anual
Área(s) de concentração: Química
Url do curso: https://quimica.vitoria.ufes.br/pt-br/pos-graduacao/PPGQ/detalhes-do-curso?id=954
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- ItemSíntese De Zeólitas A Partir De Resíduos De Rochas Ornamentais, Modificadas Com Nb2O5/SO42-, E Aplicação Como Catalisador Para Síntese De Biodiesel(Universidade Federal do Espírito Santo, 2024-02-05) Céleri, Eliomar Pivante; Barañano, Audrei Giménez ; https://orcid.org/0000-0002-0174-5202; http://lattes.cnpq.br/6155024776819193; Lacerda Júnior, Valdemar; https://orcid.org/0000-0002-8257-5443; http://lattes.cnpq.br/9819471276433138; https://orcid.org/0000-0003-0398-1687; http://lattes.cnpq.br/7451829765311645; Machado, Marta Albuquerque; https://orcid.org/0000-0001-8335-3351; http://lattes.cnpq.br/5991893415892784; Pinheiro, Patrícia Fontes ; https://orcid.org/0000-0003-4019-5773; http://lattes.cnpq.br/7891884643619330Brazil stands out as a major producer of ornamental rocks, with the state of Espírito Santo making a significant contribution by producing approximately 80% of this type of rock in the country. However, this production generates waste that requires management to mitigate environmental impacts. In this study, ornamental rock waste was used for the first time to synthesize zeolites. The waste consisted of quartz and potassium feldspars, albite, and orthoclase. Due to the mineralogical composition, the alkaline fusion method was employed to destroy the crystalline structure and obtain reactive aluminosilicates for zeolite crystallization. Crystallization took place in polyethylene flasks at 95°C for 48 hours. The results showed that, in just 6 hours of crystallization, LTA zeolites were obtained with over 99% crystallinity. After 48 hours, LTA zeolites were converted into SOD zeolites. The SOD zeolite was modified with sulfated niobium oxide, presenting a surface area of approximately 19 m2 .g-1 , pore volume of 0.076 cm3.g-¹ , and most frequent pore diameter of 3.360 nm, classified as mesoporous. LTA, SOD, and modified SOD zeolites were tested as catalysts for the transesterification of soybean oil and esterification of fatty acids for biodiesel production. Different alcohols (methanol, ethanol, butanol, and isoamyl alcohol) were used for synthesis, varying reaction parameters such as time (2 to 12 hours), temperature (60 to 100°C), and alcohol-to-oil ratio (10:1 to 25:1). Although pure SOD zeolite showed no catalytic activity for biodiesel synthesis from esterification and transesterification reactions, modification with Nb2O5/SO4²- resulted in 12% conversion for biodiesel synthesis by transesterification and 52% by esterification. Among the catalysts studied, the trend for better catalytic activity was observed for Nb2O5/SO4²- > SOD/Nb2O5/SO4²- > Nb2O5 > LTA zeolite > SOD zeolite. Finally, this study demonstrates the feasibility of using ornamental rock waste in zeolite synthesis, paving the way for innovative and sustainable applications.
- ItemReação de Mannich Com Enaminonaftoquinonas: Nova Metodologia Para a Síntese de Poliaminas Com Potencial Atividade Antiproliferativa de Células Cancerígenas(Universidade Federal do Espírito Santo, 2024-02-26) Cunha, Vinícius Souza; Greco, Sandro José; https://orcid.org/0000-0003-2382-9295; http://lattes.cnpq.br/5752788440118349; https://orcid.org/; http://lattes.cnpq.br/3385563262886342; Kuster, Ricardo Machado; https://orcid.org/0000-0002-8961-5348; http://lattes.cnpq.br/4149814906786366; Silva, Artur Manuel Soares da; https://orcid.org/0000-0003-2861-8286; http://lattes.cnpq.br/The Mannich reaction is the condensation of a substrate containing an activated hydrogen, an unenolizable carbonyl compound with a primary or secondary amine, or ammonium chloride. Modern methodologies of the Mannich reaction use pre-formed electrophilic reagents, ensuring a higher concentration of the electrophile in the reaction medium and minimizing reaction disadvantages. Enaminonaphthoquinones are compounds of the naphthoquinone class functionalized with an amino group at C2. The objective was to develop a series of novel Mannich bases using enaminonaphthoquinones and electrophilic reagents. All enaminonaphthoquinones were prepared by nucleophilic substitution or azide addition. Through methodological development, the need for highly electrophilic substrates was verified. For this purpose, pre-synthesized pyrrolidinemethyleneammonium chloride and Eschenmoser salt were used. Mannich bases 131, 132, 133, 136, 137, 138, and 139 are unpublished in the literature and were prepared with yields ranging from 10 to 88%. The structures were elucidated by infrared, 1H NMR, 13C NMR, and GC-MS. Regarding in situ cytotoxic assays, it is concluded that the compounds have greater antiproliferative activity against cancer cells than enaminonaphthoquinones for the following cancer cell lines: HCT-116 (human colon carcinoma) and PC-3 (human prostate carcinoma).
- ItemSíntese Metabólitos da Cocaína e Estudos de Métodos Analíticos a Partir de Drogas Apreendidas(Universidade Federal do Espírito Santo, 2024-03-01) Miossi, Karoline Pereira; Cunha Neto, Álvaro; https://orcid.org/0000-0002-1814-6214; http://lattes.cnpq.br/7448379486432052; https://orcid.org/0009-0001-4966-0849; http://lattes.cnpq.br/1952753362670671; Kuster, Ricardo Machado; https://orcid.org/0000-0002-8961-5348; http://lattes.cnpq.br/4149814906786366; França, Hildegardo Seibert; https://orcid.org/0000-0001-6129-8793; http://lattes.cnpq.br/1284874997224988During the year, the police seize tons of illegal drugs, such as crack and cocaine. In accordance with Law No. 12,961, art. 50-A, all seized drugs must be disposed of by incineration. On the other hand, the area of forensic chemistry has been growing and requiring increasingly efficient analysis and quantification methods. One of the objectives of this work is to compare three cocaine quantification methods: gas chromatography coupled with mass spectrometry (GC/MS), high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR). The second objective of the work is to present methodologies for obtaining reference materials (MF) for cocaine and its metabolites, from seized street crack samples. MF’s are widely used in toxicological tests (for example, doping) and in research. Since drugs are incinerated, they can be reused, like crack. Therefore, for the first, 10 samples of crack and 10 samples of street cocaine seized by the Civil Police of the State of Espírito Santo (PC-ES) were analyzed, from which the correlation coefficient (R) for the CG/EM was determined. (R = 0.9939) and HPLC (crack: R = 0.9984; cocaine: R = 0.9907). A slight difference in cocaine percentages was observed between methods. For the second objective, he isolated the cocaine present in crack and with it, through semisynthesis, synthesized the main metabolites of cocaine (ecgonine methyl ester, ecgonine and cinnamoylecgonine). The products were analyzed using NMR, GC/MS and HPLC spectroscopy techniques and Fourier transform infrared spectroscopy (FTVI) aiming to characterize and determine their purity. Therefore, the cocaine found in crack is 48.34%. For the isolation of cocaine, liquid chromatography and crystallization/recrystallization were used. For the synthesis of ecgonine, three acid hydrolysis was carried out, varying the starting material, with: pure crack, cocaine obtained by liquid chromatography and cocaine obtained by recrystallization. The latter is quantified by HPLC and NMR. From the ecgonine obtained, ecgonine methyl ester and cinnamoylecgonine were synthesized by acid catalytic esterification.
- ItemAproveitamento de Resíduos da Agroindústria Cítrica para Investigação de Moléculas com Atividade Antiproliferativa em Células de Adenocarcinoma Gástrico (AGS)(Universidade Federal do Espírito Santo, 2024-03-27) Polese, Jullia Ramos de Sousa; Lima, Tamires Aliprandi; https://orcid.org/0000-0001-5293-492X; http://lattes.cnpq.br/0339797150770837; Kuster, Ricardo Machado; https://orcid.org/0000-0002-8961-5348; http://lattes.cnpq.br/4149814906786366; https://orcid.org/0009-0003-0042-484X; http://lattes.cnpq.br/9678123245344956; Neto, Alvaro Cunha; https://orcid.org/0000-0002-1814-6214; http://lattes.cnpq.br/7448379486432052; Mathias, Leda; https://orcid.org/0000-0002-1814-6214; http://lattes.cnpq.br/4021506958174837Citrus farming is one of the most common agricultural activities in tropical and subtropical countries. However, approximately half of the total citrus fruit production is transformed into waste with a high organic matter content. These residues are rich in flavonoids, especially flavanones, which have been studied for their medicinal properties, including their use in the management of gastric cancer. Extracts from peels and pomace of citrus species consumed in the State of Espírito Santo, Brazil, were subjected to cytotoxicity tests on gastric adenocarcinoma cells (AGS) and macrophages (RAW 264.7) with the aim of selecting those with a greater possibility of use in patients with gastric cancer. The chemical similarity between them was evaluated using mass spectrometry data (ESI-FT-ICR MS) subjected to principal component analysis and liquid chromatography coupled to mass spectrometry (UPLCMS). ESI (-) FT-ICR MS made it possible to identify the presence of the flavanone’s hesperidin, eriocitrin, narirutin, hesperetin, eriodictyol, and naringenin. Cytotoxic evaluation by the MTT method showed considerable antiproliferative activity for samples of Tahiti lemon pomace extract (IC50 = 38,44 ± 0,82 μg/mL) and no toxicity in macrophages (IC50 > 800 μg/mL) at the doses tested. Tahiti lemon peel extract was considered cytotoxic to AGS (IC50 = 59,04 ± 1,06 μg/mL), but also showed cytotoxicity to RAW 264.7 macrophages (IC50 = 296,2 ± 0,13 μg/mL). The UPLC-MS technique made it possible to distinguish compounds from the flavonoid, coumarin, and limonoid classes in the Tahiti lemon peel extract sample that were not present in the pomace extract sample. The antiproliferative activity was mainly related to the presence of the flavanone’s hesperidin and eriocitrin, although samples of other citrus residues containing only hesperidin also showed antiproliferative activity at higher concentrations. To justify this hypothesis regarding the antiproliferative activity of flavanones, in silico studies were conducted on thymidylate synthase (TS) and hydroxymethylglutayl-CoA reductase (HMGCR), which are overexpressed in AGS cells. Both flavanones showed excellent anchoring in the effective sites of the enzymes, corroborating the hypothesis raised. Based on the study carried out, Tahiti lemon residues, as well as other citrus sources, can be considered promising raw materials to generate new materials for the management of gastric cancer.
- ItemPetróleo como tema gerador no ensino de química: Elaboração de um Material Didático para o Ensino Médio(Universidade Federal do Espírito Santo, 2024-02-28) Cruz, Jessika Lima; Nascimento, Marta Leite da Silva; https://orcid.org/0000-0002-0599-9576; http://lattes.cnpq.br/7796273246460962; Nascimento, Andreas; https://orcid.org/0000-0002-4465-5450; http://lattes.cnpq.br/2072155247986639; https://orcid.org/; http://lattes.cnpq.br/2054876750615116; Mantegazini, Diunay Zuliani; https://orcid.org/0000-0003-0606-5991; http://lattes.cnpq.br/1059490151468461; Moura, Paulo Rogerio Garcez de; https://orcid.org/0000-0002-6893-3873; http://lattes.cnpq.br/9815585530252572Chemistry plays a crucial role in understanding the chemical phenomena that occur in everyday life, and it is the responsibility of educators to create an environment conducive to teaching and learning. Thus, there is a need to develop instructional materials that address topics capable of promoting a dialectical relationship between scientific knowledge and everyday experiences. In this context, it is essential to address topics that establish a connection between scientific knowledge and everyday knowledge, seeking to promote critical and scientific awareness. To contextualize and stimulate critical education, themes related to Environmental Education play a crucial role, providing knowledge linked to social, economic, and political interests. This approach aims to instigate a reflection that promotes commitment to the environment, considering the complexity and multidimensionality of the environmental issue in the exercise of social participation and the defense of citizenship. However, with the implementation of the new high school curriculum, some subjects, including Chemistry, have had their workload reduced, resulting in the loss of important content for student development, such as Organic Chemistry. Faced with this scenario, this work proposes a systematic analysis of the school context of a public high school in Espírito Santo. Additionally, it seeks to apply instructional material focused on the study of Organic Chemistry content, with a specific focus on petroleum, addressing its formation, extraction, refining, and derivatives. The instructional material was built using Active Methodologies, innovative ways of educating that stimulate learning and active student participation in the classroom. This material was developed to integrate the elective subject that is part of the curriculum of the new high school in Espírito Santo. The instructional material was applied in elective classes in the years 2022 and 2023, comprising students from the 1st, 2nd, and 3rd years of high school. Some practices proposed in the material were also applied in Adult and Youth Education (EJA) classes. The research was submitted to the Brazil platform with the Certificate of Presentation for Ethical Appreciation (CAAE) number 73494123.3.0000.5542 and obtained opinion number 6,275,610. The research presents mixed characteristics, combining quantitative and qualitative data analysis. Data were obtained through the application of questionnaires, observation of didactic sequences, among others. With data analysis, the results were classified into two categories: Evolution of concepts on the petroleum theme and Evolution of chemical thinking. Through a comprehensive analysis of the research data, the importance and effectiveness of active methodologies in the chemistry teaching process are evident, particularly when dealing with complex topics related to petroleum. Throughout this research, the instructional material developed to address specific topics related to petroleum has proven to be not only an effective pedagogical tool but also a crucial facilitator for the evolution of students' concepts and chemical thinking.