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Item Estudo de degradação forçada e de compatibilidade do ciprofibrato com excipientes farmacêuticos(Universidade Federal de Goiás, 2022-08-31) Brito, Camila Cíntia Sousa Melo; Leles, Maria Inês Gonçalves; http://lattes.cnpq.br/1614912440064013; Leles, Maria Inês Gonçalves; Siqueira, Adriano Buzutti de; Chaves, Andrea Rodrigues; Ionashiro, Elias Yuki; Ribeiro, Elton BritoCiprofibrate-CPF is a hypolipidemic that promotes the reduction of serum levels of cholesterol and triglycerides by stimulating activated nuclear receptors for peroxisome proliferation-alpha-PPAR-α. In this work, the stability of CPF was studied using forced degradation and compatibility studies. The Active Pharmaceutical Ingredient-API (SQC) was characterized by Thermogravimetric Analysis/Derivative Thermogravimetric AnalysisTGA/DTGA, Differrential Scanning Calorimetry-DSC, Differrential Scanning Calorimetry coupled to the Photovisual system-DSC-Photovisual, Absorption spectroscopy in the mid-infrared region with Fourier Transform-FTIR, Nuclear Magnetic Resonance-RMN, Powder X-ray Diffractometry-DRXP, High Resolution Mass Spectrometry-EMAR and High Performance Liquid Chromatography coupled with Diode Array Detector and High Resolution Mass Spectrometry-CLAE/DAD/EMAR. The forced degradation study was carried out for CPF (SQC) under the following conditions: acid hydrolysis, basic hydrolysis, oxidative and thermal at 70 °C 240 hours using EMAR and CLAE/DAD/EMAR. The compatibility study between the CPF and the excipients was carried out by preparing binary mixtures in the proportions 50:50 and 92:08 (m/m), where the isolated components (CPF (SQT) and excipients), Simulated Excipients Sample-ASE (excipients) and the binary mixtures (CPF-excipient or CPF-excipients) were analyzed by TGA/DTGA, DSC, DSC-Photovisual, FTIR, and DRXP. The EMAR and CLAE/DAD/EMAR results suggested the degradation of CPF when subjected to basic hydrolysis, with some degradation products previously reported in the literature being observed and a new product identified. In the other exposure conditions, the CPF remained stable. The DSC technique suggested signs of interaction between the CPF and the excipients (Sodium Starch Glycolate-AGS, Sodium Lauryl Sulfate-LSS, Silicon Dioxide-DOS and Hydrogenated Vegetable OilOVH) when prepared in a proportion 50:50 (m/m) and between CPF and the excipient (OVH) in a proportion (92:08 m /m). However, the FTIR and DRXP techniques did not confirm the sings of interaction observed in the DSC, except when DOS was used at 50%. The compatibility study indicated the use of the CPF-ASE binary mixture in the proportion 50:50 (m/m) as a candidate for pre-formulation.Item Desenvolvimento de metodologias miniaturizadas de preparo de amostras para a avaliação de pesticidas multiclasses em amostras ambientais(Universidade Federal de Goiás, 2023-09-05) Martins, Rafael Oliveira; Silva, Bruno José Gonçalves da; http://lattes.cnpq.br/6550581465780888; Chaves, Andréa Rodrigues; http://lattes.cnpq.br/6064014965252121; Chaves, Andréa Rodrigues; Nascentes, Clésia Cristina; Coltro, Wendell Karlos Tomazelli; Hantao, Leandro Wang; Sgobbi, Lívia FlórioThe presence of pesticides in the environment is primarily due to the excessive use of these chemical compounds in the global agricultural scenario. In recent decades, the search for new approaches to the analysis and monitoring of these compounds in such matrices has focused on the introduction of sample preparation methodologies as analytical strategies responsible for assessing such complex matrices. Furthermore, the evolution of these sample preparation methodologies over the decades has brought with it the introduction of miniaturized systems capable of overcoming classical challenges faced by conventional sample preparation method-ologies. Thus, this study presents the evaluation of three miniaturized approaches for pesticide extraction in environmental samples. Chapter II presents the development and application of the Hollow Fiber Liquid-Phase Microextraction (HF-LPME) technique for the assessment of 13 multi-class pesticides in soil samples. The methodology reported in the first chapter resulted in R² values >0.98 for all pesticides and detection and quantification limits (LOD and LOQ, re-spectively) in the range of ng L-1 and recovery values between 75.2%-118.8%. The evaluation of the methodology proposed by the AGREEprep software indicated that approximately 70% of the method adhered to the principles of green chemistry adopted by the software. Furthermore, a comparison with classical methods of pesticide extraction in soil identified the HF-LPME method as an efficient approach for monitoring pesticides in soil. Chapter III describes the application of the Electromembrane Extraction (EME) technique for the evaluation of the same set of analytes in soil samples. In this second approach, a special focus was placed on com-paring the proposed method with the one applied in Chapter II, regarding analytical frequency, green aspects, and analytical performance of both methods. Differences were observed in an-alytical aspects, where the EME technique showed higher LOD (76.1 -171.4 μg kg-1) and LOQ (270.7 -516.1 μg kg-1) values than the HF-LPME technique (66.1 -198.1 μg kg-1) and (92.7 -331.2 μg kg-1), respectively. Despite this, values closer to 100% were obtained with the EME technique. A higher analytical frequency was achieved with the EME technique (4 extractions/h) compared to HF-LPME (2 extractions/h). Regarding green chemistry aspects, due to the use of external energy, the methodology proposed by EME showed significant energy consumption. Finally, Chapter IV presented a detailed study of the influence of parameters involved in the on-chip electromembrane extraction technique of the pesticides Carbofuran and Carbendazim in river water samples. This chapter focused on two main aspects: (I)the optimization of the device to reduce leakage during extraction, as it is a disadvantage of the conventional system, and (II)evaluating the differences in the extraction of ionizable and neutral compounds by the on-chip electromembrane extraction system. The optimization of the device introduced the OSTE sealing material as an approach to prevent leaks, allowing for the use of flow rates of 300 μl/min-1 without observing leaks. The evaluation of the parameters involved in the technique showed the dependence of the physicochemical characteristics of the pesticides on the pro-posed system, revealing the extraction of the pesticides in their charged and neutral forms. The analytical evaluation of the method showed LOD and LOQ values ranging from 158.4 to 256.2 μg L-1and 528.1 to 854.1 μg L-1, respectively, and recovery values ranging from 26.3% to 53.8%, indicating an influence of the matrix that was confirmed by the matrix effect study. The study of the pesticides Carbaryl and Carbendazim proved to be an important approach to further expand the field of applications of the on-chip electromembrane extraction technique. The methods described here have proven to be effective analytical strategies for assessing pesticides in en-vironmental samples. The development of the methodologies presented here further expands the possibilities for monitoring pesticides in such complex samples as environmental ones. The application of the proposed methodologies offers a possible strategy for evaluating the effects of these compounds on the environment and proposing ways to identify contaminants in differ-ent environmental compartments.Item Análise de íons inorgânicos em resíduos de explosão utilizando microssistemas eletroforéticos(Universidade Federal de Goiás, 2018-08-01) Pinheiro, Kemilly Mara Pires; Coltro, Wendell Karlos Tomazelli; http://lattes.cnpq.br/8302650734477213; Coltro, Wendell Karlos Tomazelli; Rosseto, Renato; lonashiro, Elias YukiThis study describes the development of an analytical methodology based on the use of microchip electrophoresis (MSE) devices integrated with capacitively coupled contactless conductivity detection (C4D) for the separation and detection of inorganic anions in post-blast explosive residues. The best separation condition was achieved using a running buffer composed of 35 mmol L-1 lactic acid, 10 mmol L-1 histidine and 0.070 mmol L-1 cetyl(trimethyl ammonium) bromide. For C4D measurements, the highest sensitivity was obtained applying a 700 kHz sinusoidal wave with excitation voltage of 20 Vpp. The separation of Cl-, NO3-, NO2-, SO42-, ClO4- and ClO3- was performed within ca. 150 s with baseline resolution and efficiencies between 4.4x104 and 1.7x105 plates/m. The found limits of detection ranged between 2.5 and 9.5 μmol L-1. Also, excellent repeatability was obtained, with relative standard deviation lower than 0.8%, 8.8% and 13.5% for the injection time, for the intensity and the peak areas, respectively. Lastly, real samples of post-blast explosive residues were analyzed on the MSE-C4D devices obtaining successfully the determination of Cl-, NO3- and SO42-. The achieved concentration values varied between 2301,610 µg g-1 for Cl-, 805,490 µg g-1 for NO3- and 1453,270 µg g-1 for SO42-. It was also possible to compare the anionic profile of residues of an improved explosive device and a commercial explosive emulsion, confirming the improved explosive device composition, based on ammonium nitrate fuel oil (ANFO). The approach reported herein has provided short analysis time, instrumental simplicity, good analytical performance and low cost. Furthermore, the MSE-C4D devices emerge as a powerful and portable analytical platform for on-site analysis demonstrating to be a promising tool for the crime scene investigation.Item Determinação de ácidos orgânicos em amostras alimentícias e petroleômicas utilizando sistemas eletroforéticos(Universidade Federal de Goiás, 2022-06-30) Pinheiro, Kemilly Mara Pires; Coltro, Wendell Karlos Tomazelli; http://lattes.cnpq.br/8302650734477213; Coltro, Wendell Karlos Tomazelli; Vaz, Boniek Gontijo; Lago, Claudimir Lúcio do; Richter, Eduardo Mathias; Micke, Gustavo AmadeuThis study describes the use of microchip electrophoresis coupled to contactless conductivity detection for the determination of inorganic and organic anions for food and petroleomics application. Also, describes the use of capillary electrophoresis coupled to mass spectrometry for petroleomic application. Organic acids are responsible for several wines characteristics, such as aroma, flavor, color and stability. Their analysis are important for monitoring fermentation process and the quality of wines. 12 anions were detected and separated within 100 s, using a buffer composed of 30 mmol L-1 OF 2-(N-Morpholino)ethanesulfonic acid, 15 mmol L-1 of histidine and 0.05 mmol L-1 of cetyltrimethylammonium bromide (pH 5.8). 18 wine samples were analyzed and it was possible to detect and quantify sulfate, phosphate, tartrate, maleate, succinate, acetate and lactate. A multivariate approach was used to investigate the similarities among anionic profile of the wines, and it was possible to discriminate samples mainly by grape varieties, production region and winemaking process. Naphthenic acids are carboxylic acids naturally occurring in crude oil with one or more ring structures. They are present in produced water, which is the water obtained with petroleum during its prospection and are responsible for corrosion, naphthenates deposition, and harmful to the environment when disposed of without treatment. The acids benzoic, 1-naphthoic and 9-anthracenecarboxylic were separated and detected using a microsystem electrophoresis coupled to contactless conductivity detection. The analysis was performed within 140 s using a buffer composed of an equimolar mixture of 10 mmol L-1 of sodium carbonate and bicarbonate (pH 10.2). 5 samples of produced water were analyzed and it was possible to detect and quantify 9-anthracenecarboxylic acid, demonstrating to be an efficient tool for analysis of complex samples matrices for petroleum applications. In this way, electrophoresis microchip proves to be a simple and portable analytical platform for field analysis, proving to be promising for wine quality control and for monitoring the presence of naphthenic acids in produced water samples. A capillary electrophoresis system coupled to a mass spectrometer was also used to analyze naphthenic acids. It was possible to detect cyclopentanecarboxylic acid, benzoic acid, cyclohexanebutyric acid, 1-naphthoic acid, decanoic acid, 3,5-dimethyladamantane-1-carboxylic acid, 9-anthracenecarboxylic acid, pentadecanoic acid and 2-methyl-octadecanoic acid within 13 min using a buffer composed of 40 mmol L-1 of ammonium hydroxide, 32 mmol L-1 of acetic acid and 20% isopropanol (pH 8.6). Produced water samples were analyzed and it was possible to identify and quantify cyclopentanecarboxylic, benzoic, cyclohexanebutyric and decanoic acids. In this way, the proposed method demonstrated to be efficient to detect naphthenic acids analysis in complex samples of produced water using capillary electrophoresis coupled with mass spectrometry. The next steps of this study are the evaluation of other acids in produced water samples for quantification of total acids.Item Determinação de escopolamina e butilescopolamina em amostras de bebidas, urina e comprimidos de Buscopan® usando microssistemas eletroforéticos(Universidade Federal de Goiás, 2023-08-08) Santos, Hellen Inácia dos; Coltro, Wendell Karlos Tomazelli; http://lattes.cnpq.br/8302650734477213; Coltro, Wendell Karlos Tomazelli; Jesus, Dosil Pereira de; Chaves, Andréa RodriguesThe number of cases in which scopolamine (SCO) was used for both recreational and predatory purposes has increased dramatically in recent decades. Linked to this, there is a concern about obtaining SCO through thermal degradation of butylscopolamine (BSCO) – an active ingredient of Buscopan® – a drug sold without a medical prescription. In this study, mixtures containing SCO and BSCO were separated and detected on a microchip electrophoresis (ME) device with integrated capacitively coupled contactless conductivity detection (C4D) using a running buffer composed of 40 mmol L-1 of butyric acid and 25 mmol L-1 of sodium hydroxide (pH 5.0). The separation was performed within ca. 115 s with a resolution of 1.3 and separation efficiency of 1.4x105 and 1.5x105 theoretical plates m-1 for SCO and BSCO, respectively. The limit of detection was 1.1 μmol L-1 for both species and the developed method revealed satisfactory repeatability with relative standard deviation (RSD) values for forty-eight injections between 4.8 and 9.4% for peak areas and lower than 3.3% for migration times. Furthermore, inter-day precision was evaluated for sixteen injections (a sequence of four injections performed over four days), and RSD values were less than 6.6% for peak areas and 2.2% for migration times. Satisfactory recovery values (95 – 114 %) were obtained for all evaluated beverage samples (cachaça, vodka, whiskey, beer, coke soft drink, and grape juice) as well as for artificial urine samples (95 – 107 %). Finally, the conversion of BSCO into SCO was observed after simple heating procedure of Buscopan® sample (not subject to medical prescription), which was successfully confirmed through analysis by capillary electrophoresis coupled to the mass spectrometry (CE-MS). Based on the reported results, the use of ME-C4D devices has demonstrated a huge potential for applications in the forensic chemistry field.