Self-Assembly of Vesicles from Oligoaramide Based on Multiple Hydrogen Bonds

Abstract

Six-hydrogen-bonded oligoaramide heteroduplexes demonstrate extremely high sequencespecificity and tunable stability during their self-assembly. The self-assembly behavior of molecular oligoaramide1 arrayed in a DADDAD-DADDAD sequence and that in the presence of oligoaramide 2 with an ADAADAADAADA sequence were examined using multiple techniques, including scanning electron microscopy(SEM),transmission electron microscopy(TEM), and dynamic light scattering(DLS). Results from these experiments indicate that 1 can self-assemble to vesicles with uniform shapes in both tetrahydrofuran/methanol(V/V, 85/15)and acetone, the size of which increased with an increase in solution concentration. Upon addition of the corresponding complementary 2, the vesicles turned into solid balls. Fluorescence microscopy experiments revealed that the vesicles were able to encapsulate the fluorescence molecules(Rhodamine B). With further modification of molecular structures, these vesicles may hold potential for applications as drug carrier as well as in controlled-release technology.