Publicação
Self-assembled noncovalent hydrogels based on dehydrodipeptides
| Resumo: | Self-assembly of nanometric structures from molecular building blocks is an effective way to make new functional materials for biological and technological applications. In this work we synthesized new N-modified dehydrodipeptides based on phenylalanine and dehydroamino acid units attached to aromatic modifiers, namely trimesoyl, terephtaloyl, diphenylacetyl and 2,2´-(1,3-phenylene)diacetyl in a pattern that afforded mono or polysubstitued organic molecules. The potential use of these new compounds as hydrogelators was evaluated. The results showed that most of the prepared compounds behave as efficient molecular hydrogelators forming hydrogels at minimum gelation concentrations of 0.3-0.8 wt%. Two new compounds failed to form hydrogels probably due to unfavorable thermodynamic contribution of intermolecular interactions. The self-aggregation pattern of the hydrogelators was investigated by STEM microscopy technique, revealing different shapes depending on the N-aromatic moiety. A circular dichroism analysis was also performed in order to evaluate if the peptides aggregate into any characteristic secondary structure, usually found in protein folding. We found that the 5 hydrogelators had characteristic signals, demonstrating the presence of organized structures even below the minimum gelation concentration. At elevated pH or for the non-hydrogelating compounds, it was not observed signals indicative of the presence of such structures. |
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| Autores principais: | Andrade, Juliana J. |
| Assunto: | Hydrogels Hydrogelators Dehydrodipeptides Dehydroamino acids Hidrogéis Desidro-aminoácidos Desidrodipéptidos |
| Ano: | 2012 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade do Minho |
| Idioma: | inglês |
| Origem: | RepositóriUM - Universidade do Minho |
| Resumo: | Self-assembly of nanometric structures from molecular building blocks is an effective way to make new functional materials for biological and technological applications. In this work we synthesized new N-modified dehydrodipeptides based on phenylalanine and dehydroamino acid units attached to aromatic modifiers, namely trimesoyl, terephtaloyl, diphenylacetyl and 2,2´-(1,3-phenylene)diacetyl in a pattern that afforded mono or polysubstitued organic molecules. The potential use of these new compounds as hydrogelators was evaluated. The results showed that most of the prepared compounds behave as efficient molecular hydrogelators forming hydrogels at minimum gelation concentrations of 0.3-0.8 wt%. Two new compounds failed to form hydrogels probably due to unfavorable thermodynamic contribution of intermolecular interactions. The self-aggregation pattern of the hydrogelators was investigated by STEM microscopy technique, revealing different shapes depending on the N-aromatic moiety. A circular dichroism analysis was also performed in order to evaluate if the peptides aggregate into any characteristic secondary structure, usually found in protein folding. We found that the 5 hydrogelators had characteristic signals, demonstrating the presence of organized structures even below the minimum gelation concentration. At elevated pH or for the non-hydrogelating compounds, it was not observed signals indicative of the presence of such structures. |
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