Lipophilic guanines (LipoGs) in aprotic solvents undergo different self-assembly processes based on different H-bonded motifs. Cylindrical nanotubes made by π-π stacked guanine tetramers (G-quadruplexes) and flat, tape-like aggregates (G-ribbons) have been observed depending on the presence of alkali metal ions. To obtain information on the structural properties and stability of these LipoG aggregates, Small-Angle X-ray Scattering (SAXS) experiments have been performed in dodecane, both in the presence and in the absence of potassium ions. As a result, the occurrence of the two different metallo-responsive architectures (nanoribbons or columnar nanotubes) was confirmed and we reported here for the first time a systematic study on the dependence of the aggregate properties on composition, temperature and molecular unit structure. Even if dodecane was selected to favour LipoG solubility, a strong tendency to self-organize into ordered lyotropic phases was indeed detected.
Metallo-responsive self-assembly of lipophilic guanines in hydrocarbon solvents: A systematic SAXS structural characterization / Gonnelli, A.; Pieraccini, S.; Baldassarri, E. J.; Funari, S.; Masiero, S.; Ortore, M. G.; Mariani, P.. - In: NANOSCALE. - ISSN 2040-3364. - STAMPA. - 12:2(2020), pp. 1022-1031. [10.1039/c9nr08556d]