| Texto completo | |
| Autor(es): |
Pepe, Alessia
;
Moretti, Paolo
;
Yoneda, Juliana S.
;
Carducci, Federica
;
Itri, Rosangela
;
Mariani, Paolo
Número total de Autores: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | NANOSCALE; v. N/A, p. 10-pg., 2023-08-10. |
| Resumo | |
Guanine (G) hydrogels are very attractive materials made by the supramolecular organization of G-derivatives in water. In this paper, hydrogels composed of guanosine 5 & PRIME;-monophosphate (GMP) and guanosine (Gua), that make long, flexible and knotted G-quadruplexes, were investigated by small- and wide-angle X-ray scattering (SAXS and WAXS) to comprehend the origin of their unique orientational properties. The SAXS intensity, analysed at a fixed scattering vector modulus Q as a function of polar angle, allowed us to derive the Maier-Saupe orientation parameter m. The strong dependence of m on hydrogel composition and temperature demonstrated that the preferred orientation is controlled by the quadruplex surface charge and flexibility. Indeed, a possible correlation between the orientation parameter m and the quadruplex-to-quadruplex lateral interactions was explored. Results confirmed that the balance between attractive and repulsive interactions plays a main role in the orientational anisotropy: quadruplex clusters lose their orientational properties when attractive interactions decrease. The key role of the number of negative charges per unit length of the G-quadruplex filaments was confirmed by Atomic Force Microscopy (AFM) observations. Indeed, directionality histograms showed that in the presence of a large amount of Gua, G-quadruplexes follow preferential orientations other than those related to the strong interactions with the K+ pattern on the mica surface. The fact that lateral quadruplex-to-quadruplex interactions, even in the presence of external (opposing) forces, can tune the hydrogel alignment in a given preferred direction provides novel possibilities for scaffold/3D printing applications. Guanine (G) hydrogels are very attractive materials made by the supramolecular organization of G-derivatives in water. (AU) | |
| Processo FAPESP: | 18/07194-9 - Hidrogel de G-quadruplex como Potencial Carregador de Fotossensibilizadores para Aplicação em Terapia Fotodinâmica |
| Beneficiário: | Juliana Sakamoto Yoneda |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |