| Texto completo | |
| Autor(es): |
Carvalho, Lucas Braganca
;
Jaime, Carlos
;
Venancio, Tiago
;
Fraceto, Leonardo Fernandes
;
Pinto, Luciana Matos Alves
Número total de Autores: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Molecular Structure; v. 1347, p. 12-pg., 2025-12-15. |
| Resumo | |
Methyltestosterone (MT) is a steroid widely used in animal production techniques, especially in aquaculture. A combination of MT and cyclodextrin can cause changes in the physicochemical and steroid release profile, providing a desirable effect with relatively low doses. In this study, inclusion complexes between MT and gamma-cyclodextrin (gamma-CD) were prepared and characterized in solution and solid phases. The use of gamma-CD enhanced the apparent solubility of the steroid by 17-fold, and the inclusion complex formed exhibited 1:1 stoichiometry. The association constant (Ka) was determined under two distinct solvent conditions: 26,600 L mol-1 by solubility isotherm in water, and a lower value of 10,970 L mol-1 by DOSY-NMR using a DMSO-d6/D2O mixture, highlighting the impact of the solvent environment on complex stability. The fraction of the steroid complexed with gamma-CD was similar in the liquid and solid phases, with 86 % and 83 % values, respectively. Two-dimensional rotating-frame Overhauser enhancement spectroscopy (2D ROESY) experiments indicated intermolecular orientation (the complete inclusion of the hormone in the cavity), with the carbonyl facing the gamma-CD rim flanked by secondary hydroxyls. Molecular dynamics simulations corroborated the formation of the 1:1 inclusion complex. In vitro release tests showed that, for the complex, the diffusion of MT through the membrane was approximately 40 % slower than that in its free form. These results demonstrated the complexation of MT in gamma-CD; the combination of these compounds is very promising for future applications involving this steroid in aquaculture, both for sex reversal and in-water hormone sequestration technologies. (AU) | |
| Processo FAPESP: | 21/10639-5 - Centro de Pesquisa em Biodiversidade e Mudanças do Clima |
| Beneficiário: | Leonor Patricia Cerdeira Morellato |
| Modalidade de apoio: | Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs |
| Processo FAPESP: | 18/23608-8 - Desenvolvimento de nanopesticidas marcados com sondas fluorescentes para estudos de mecanismo de ação e toxicidade |
| Beneficiário: | Lucas Bragança de Carvalho |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |