Detalhes bibliográficos
| Ano de defesa: |
2024 |
| Autor(a) principal: |
Romanholo, Pedro Victor Valadares
 |
| Orientador(a): |
Sgobbi, Lívia Flório
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| Banca de defesa: |
Sgobbi, Lívia Flório,
Martins, Paulo Roberto,
Jost, Cristiane Luísa,
Galli, Andressa,
Madurro, João Marcos |
| Tipo de documento: |
Tese
|
| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Federal de Goiás
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| Programa de Pós-Graduação: |
Programa de Pós-graduação em Química (IQ)
|
| Departamento: |
Instituto de Química - IQ (RMG)
|
| País: |
Brasil
|
| Palavras-chave em Português: |
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| Palavras-chave em Inglês: |
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| Área do conhecimento CNPq: |
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| Link de acesso: |
http://repositorio.bc.ufg.br/tede/handle/tede/13373
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Resumo: |
This work presents the fabrication methods and the application of two electrochemical systems. The frst one, named yin-yang method, comprises the development of a novel approach for the simultaneous detection of two solvent incompatible molecules, ascorbic acid (vitamin C), and cholecalciferol (vitamin D3). For that end, two electrochemical cells were arranged in a parallel array, resulting in an analytical method capable of simultaneously measuring the output signal of both analytes in a single run. The main goal of this method lies on the possibility of bypassing the analytical limitations present when both analytes are prepared in a single medium, since vitamin C is readily soluble in water but vitamin D3 hardly solubilizes in the same concentration range. Due to the solubilization impairment, the electrochemical output presents with low resolution when both vitamins are collectively analyzed in a single medium, which also impacts the detection since the electrochemical potential shifts considerably. Results showed that the yin-yang method is reliable, may avoid the use of multichannel potentiostats, and might improve analytical parameters. The second system is presented as a wearable paper-based electrochemical platform employed for the continuous monitoring of sweat glucose levels. The device is fabricated with an iontophoretic stage through which sweat stimulating molecules are delivered across the skin to achieve higher fuid fow-rate, while also employing polyacrylamide gels capable of enhancing osmotic pressure to further increase sweat production. The sensor operates by wicking the biofuid directly from skin through a paper patch, which works as substrate for a glucose oxidase modifed electrode to detect changing levels of glucose. Results showed that the device allows the use for extended periods of time by an individual, displaying matching behavior with that of commercial devices. The output signal stability and resolution are shown to be fow-rate dependent and are infuenced by the individual sweat production profle |
