Nano- and Microstructure Fabrication by Using a Three-Component System

摘要

Two-component amphiphiles based on hydrogen-bonded complexes between terephthaloylbisalanine (H₂TBA) and dodecylamine (DA) are able to self-assemble into nano- and microsized superstructures in an aqueous solvent. It is possible to modulate the morphology of these self-assembled superstructures by modifying the composition of the complexes, which can be achieved by changing the molar ratio of the two components or by changing the chirality of H₂TBA. For example, right-handed microhelical ribbon structures were formed with L-TBA_1.0DA_2.0, whereas in the case of rac-TBA_1.0DA_2.0, flat ribbonlike structures were observed. Although L-TBA_1.0DA_1.0 exhibited entangled fibrous structures, rac-TBA_1.0DA_1.0 exhibited wire structures. Different ratios of H₂TBA and DA were self-assembled into fiber-, wire-, and tubulelike superstructures, as well as monoclinic, columnar, and lamellar aggregation patterns. The self-assembled superstructures of TBA_xDA_y were significantly changed by adding metal ions. Transition metal (CdII, CoII, and ZnII) complexes with L-TBA_xDA_y self-assembled into rod-, tubule-, wire-, and platelike superstructures. Metal-ion complexes with rac-TBA_xDA_y exhibited different superstructures. Our work suggests that it is possible to fabricate a wide variety of nano- and microsized superstructures by using two- and three-component amphiphiles.