Detalhes bibliográficos
| Ano de defesa: |
2019 |
| Autor(a) principal: |
Krawczak, Katianne Wolf |
| Orientador(a): |
Ourique, Aline Ferreira |
| Banca de defesa: |
Marchiori, Marila Crivellaro Lay,
Silva, William Leonardo da |
| Tipo de documento: |
Dissertação
|
| Tipo de acesso: |
Acesso embargado |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Franciscana
|
| Programa de Pós-Graduação: |
Programa de Pós-Graduação em Nanociências
|
| Departamento: |
Biociências e Nanomateriais
|
| 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://www.tede.universidadefranciscana.edu.br:8080/handle/UFN-BDTD/905
|
Resumo: |
Ascorbyl palmitate (or L-ascorbyl-6-palmitate) is a more stable and liposoluble derivative of vitamin C, it may be an agent for incorporation into topical formulations. Among its advantages is the antioxidant activity very similar to vitamin C, since it penetrates more easily in the skin when compared to vitamin C and allows a greater protection of the skin components against the action of free radicals. However, the antioxidant activity of ascorbyl palmitate can be compromised due to the physical-chemical instability of this active against photodegradation. In addition, ascorbyl palmitate is insoluble in water and nanotechnology is a tool that can allow the minimization of this factor, improving stability and avoiding the degradation of the active. Thus, the objective of this work is to prepare, characterize and evaluate the antioxidant and cytotoxic activity of nanostructured formulations containing ascorbyl palmitate for future applications in the aesthetic area. Nanoemulsions had a mean droplet size of 200 nm ± 4.02, a polydispersity index of 0.186 ± 0.021, zeta potential of -12 mV ± 2.14 and pH around 3.61 ± 0.02. The morphology of the nanoemulsions containing ascorbyl palmitate was performed by atomic force microscopy and the results found corroborated with the mean diameter values obtained by dynamic light scattering and the ascorbyl palmitate content in the formulations was 1 mg / mL. Stability results achieved during 30 days storage of samples at different temperature conditions demonstrated that ascorbyl palmitate nanoemulsions stored under refrigeration remained stable, with no change in mean droplet diameter, polydispersity index, zeta potential, pH and content thereof. Cytotoxicity tests showed that the decrease in cell viability in VERO and Fibroblast 293T cells did not occur as a result of the active, but the other components present in the formulations, since free form ascorbyl palmitate did not interfere in cell viability. As for the results of the antioxidant activity presented by the nanoemulsions, there was a gradual decrease in the activity of the samples stored in the different temperature conditions during the 30 days of analysis. The incorporation of Ascorbyl palmitate-containing nanoemulsions into hydrogels showed that it was feasible to maintain their characteristics and the hydrogels stored on refrigeration were more suitable for appearance, color and odor, diameter, polydispersity index, pH and content. According to the results obtained in this work, it can be concluded that the incorporation of the nanoemulsions containing ascorbyl palmitate in Carbopol Ultrez 10 NF allowed a greater protection of the active and the physical chemical characteristics remained even after the incorporation. |
