http://repositorio.ufc.br/handle/riufc/312 2026-04-05T13:57:15Z http://repositorio.ufc.br/handle/riufc/85484 Título: Estudo computacional da interação de fármacos anti-Parkinson com nanoestruturas de carbono Autor(es): Mendonça, Glaydson Leandro Farias Abstract: One of the consequences of increased life expectancy is the higher incidence of cases of neurodegenerative diseases, more common in older people. The most present in this category are: Alzheimer's disease and Parkinson's disease. The treatment of patients with Parkinsonism is often extremely exhausting, full of adverse effects; in certlin cares, the use of anti-Parkinson's drugs must cease so that individuals do not die or have permanent sequelae. Non-toxic nanostructured carbon particles interact with drugs, forming supramolecules capable of crossing the blood-brain barrier more easily, this show characteristics of good drug delivers. The present work aims to computationally study the interaction of the anti-Parkinson drugs Levodopa (LDP), Carbidopa (CDP), Entacapone (ECP) and Benserazide (BZD) with carbon nanostructures: Fullerane (C60), Single-walled carbon nanotube (NTCPS) and Fullerol (C60OH24) with the purpose of evaluating the application of these nanoparticles in a Drug delivery system. Molecular properties were obtained using DFT-level calculations, aiming to correlate them with pharmacological activity, as well as estimating the preferential adsorpition sites. The drug-nanostructure interactions were made using Monte Carlo and Molecular Dynamics Methods, obtaining the interaction energies and preferred orientations. It was observed that the interaction of drugs with C60 and NTCPS resulted in physical adsorption, where ECP binds more strongly to nanostructures, followed by LDP, BZD and CDP respectively, results attributed to molecular properties, such as LUMO and the electron density distribution in drugs. In the interaction of the molecules with C60OH24, chemisorption was observed, a consequence of the interaction of the heteroatoms of the drugs with the hydroxyl groups of the nanostructure, the interaction force undergoes a change and is shown as: ECP > BZD > CDP > LDP. As a final consideration, we have a potential suggestion for the treatment of Parkinson's disease would be the administration of LDP and CDP together with the carbon nanotube, making the drugs adhere to the carbon structure, facilitating the passage of drugs through the blood-brain barrier and potentially be released in the brain region, thus ensuring better use of the pharmacological effects of the drugs. Tipo: Tese 2017-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/85094 Título: Computational analysis of CO2 capture through deep eutectic solvents and silver nanoparticles Autor(es): Bezerra, Lucas Lima Abstract: The high levels of greenhouse gas (GHG) emissions in the atmosphere, especially CO2, are driving global warming, which is causing several problems for society, such as droughts, hurricanes, heat waves, and floods. Therefore, it is urgent to capture CO2 gas. In this thesis, the first work analyzed the effect of increased temperature on CO2 absorption using a deep eutectic solvent (DES) based on urea and choline chloride (reline) through molecular dynamics (MD) simulations and non-covalent interactions (NCI). Posteriorly, the second work analyzed the synergistic effect of three DESs (ethaline, reline, and glyceline) and a silver nanoparticle (AgNP) in the CO2 capture process through MD simulations. In the first work, it was observed that the increased temperature effect occasioned the reduction of the hydrogen bond (HB) number between the CO2 molecules and the urea molecules, resulting in the highest total interaction potential energy (IPE), indicating that the CO2 absorption process is more indicated at 303 K, with an average IPE value of -3872.54 kJ mol-1. On the other hand, the NCI results indicated that the increased temperature effect resulted in increased repulsion interactions and reduced the strong interactions in the systems simulated. Therefore, both computational approaches suggested that the CO2 absorption process is more indicated at the temperature of 303 K. In the second work, it was registered that the AgNP presence increases the HB number between the CO2 gas and the molecules that act as hydrogen bond donors (HBD), resulting in the lowest total IPE values for this group, occasioning a better CO2 capture process, especially for the AgNP-reline-CO2 system, with an average IPE value of -757.68 kJ mol 1. The radial distribution function (RDF) analysis indicated that ethylene glycol and urea are key species in the CO2 capture process for the AgNP-ethaline-CO2 and AgNP-reline CO2 systems, respectively. Furthermore, the AgNP is the key species in the CO2 capture process for the AgNP-glyceline-CO2 system. Tipo: Tese 2026-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/84203 Título: Phenolic compounds: a theoretic-computation study of antioxidant capacity of cardanol and eugenol Autor(es): Cândido Júnior, José Roberval Abstract: The study and development of antioxidants has an important role in technological and health areas. Naphthenic mineral oil and biodiesel modifies its physical and chemical properties due to action of reactive oxygen species (ROS) over time, affecting their performance. Our body tends to maintain a balance between antioxidant and radical species. However, as we age, the number of radicals increases, the balance is broken resulting in a condition known as oxidative stress. This condition is associated with thrombosis, heart attack, depression and cancer. Therefore, it is important the study of antioxidants and the development of new compounds with antiradical activity to increase storage time of naphthenic mineral oil and biodiesel, and avoid conditions associated with excess radicals in the body. In this context, in this work we carried out two studies. In the first, the antioxidant activity of saturated cardanol, monoene, diene and triene was computationally evaluated, with the functional hybrid B3LYP with the base set 6-31G(d,p). Using chemical quantum descriptors, the HAT, SPLET and SET-PT mechanisms were evaluated. The data obtained suggest that the HAT mechanism is the main form of action of these molecules. The analysis of the Fukui index confirms the experimental data of the best antioxidant profile of cardanol monoene. The global reactivity analysis shows that the greater the number of unsaturations in the cardanol side chain, the greater its overall reactivity. In the second study, the effect of acetylation and nitration on the antioxidant potential of eugenol and its results were evaluated. For this study, the hybrid functional M06-2X with a set of bases 6-31+G(d,p) was used to simulate the mechanism of HAT with the HO, HOO, CH3O, DPPH radicals. The thermodynamic data showed a dependence of the formation of p-quinomethanes (27, 28 and 29) to make the reaction spontaneous with DPPH, revealing the need for two steps of HAT. The kinetic data that showed the preferred site for hydrogen transfer depends on the instability of the attacking radical. The computational data corroborated the experimental data, confirming the antioxidant profile of (1, 4-allyl-2-methoxyphenol), and nitro-derivative 7 (5-allyl-3-nitrobenzene-1,2-diol) in the DPPH assay. Finally, this study showed that the nitro compound 6 (4-allyl-2-methoxy-6-nitrophenol) has antiradical activity with HO, HOO and CH3O radicals, but the repulsion between the nitro groups with DPPH makes it difficult to approach the DPPH molecule making the reaction be slow and undetectable experimentally. Tipo: Tese 2022-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/83765 Título: Desenvolvimento e aplicação de métodos sustentáveis de geração de vapor para determinação de elementos traço por técnicas espectrométricas Autor(es): Brito, Jane Kelly Sousa de Abstract: The analysis of trace elements using spectrometric techniques requires efficient sample introduction systems. However, conventional nebulizers have limitations for trace-level species such as Cr and Hg. Thus, this study proposed sustainable vapor generation methods as alternatives to traditional systems, reducing the use of expensive, unstable, and potentially toxic reagents. For Cr, a photochemical vapor generation (PVG) methodology coupled to Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) was proposed, using a UV reactor operating in continuous flow mode and using a standard Cr3+ solution of 50 µg L-1 in formic acid medium. The parameters evaluated included: formic acid concentration (10 - 40% v v-1), type of photochemical reactor, irradiation time (15 - 90 s), and N₂ carrier gas flow rate (20 - 60 mL min-1). The best conditions were obtained with a 19 W internal flow UV photoreactor, 30% v v-1 formic acid, an irradiation time of 60 s and a N₂ flow rate of 40 mL min-1. For Hg, the Thermochemical Vapor Generation (TVG) technique coupled with CV-AAS was applied to water and sediment samples from estuaries in Northeast Brazil. Hg concentrations in sediments ranged from 24.9 to 28.5 µg kg-1 in the Parnaíba Delta and reached 89.7 ± 7.1 µg kg-1 in the Cocó River. These values remained below the limits established by CONAMA Resolution No. 452/2012, indicating a low ecotoxicological risk associated with the analyzed sediment fraction. For water samples, concentrations between 2.2 ± 0.4 and 10.1 ± 1.2 µg L-1 were observed. When compared to the reference values defined by CONAMA Resolution No. 357/2005 for Class 1 brackish and saline waters (0.2 µg L-1), all results exceeded the established limit, highlighting the need for attention to the environmental quality of these estuarine ecosystems. The sustainability of the methods was evaluated using the AGREE tool, which integrates the 12 principles of Green Analytical Chemistry into a single metric (0 - 1). The results confirmed the green nature of the proposed approaches, highlighting their potential for efficient environmental monitoring of trace elements. Tipo: Tese 2025-01-01T00:00:00Z