Selective Construction of Supramolecular Nanotube Hosts with Cationic Inner Surfaces

Abstract

Self‐assembly of an unsymmetrical bolaamphiphile produces either lipid nanotubes with cationic inner surfaces or nanotapes, depending on the initial molecular packing, which in turn depends on the solvent conditions. The nanotubes have different inner and outer surfaces, covered with amino and sugar functionalities, respectively, and effectively encapsulate anionic nanomaterials in the hollow cylinder without depending on capillary action (see Figure).

Self‐assembled organic nanotubes: Toward attoliter chemistry

“…Consequently, we have achieved the efficient encapsulation of the anionic guests into the hollow cylinder without depending on lyophilization and capillary action. 51 The identical nanotube also proved to encapsulate a double-stranded DNA (T4GT7-DNA, 166 kbp and 56 lm long) on the basis of fluorescence resonance energy transfer (FRET) experiment using the fluorescent donor YOYO1 and the fluorescent acceptor DABCYL (Fig. 9).…”

“…Based on the similar design concept as mentioned earlier, we also synthesized a series of amine-based amphiphiles 2(n) (n ¼ 12, 14, 16, 17, 18, and 20) (Scheme 1) whose oligomethylene spacer length varies from C12 to C20. 51,52 The obtained long-range ordering (d ¼ 3.65 nm) by XRD and a single IR band at 1464 cm À1 for the self-assembled organic nanotube from 2(18) supported head-to-tail packing of unsymmetrical monolayer membranes (Fig. 6).…”

“…76,77 This theoretical D-value is well compatible with our experimental results for the solid-state organic nanochannels with two open ends. We can envisage several possible causes for the relatively smaller D values: electrostatic attraction between charged surfaces of the nanotube and guest, 51,53 relatively larger viscosity of the confined water, 61 and diffusion in a restricted geometry. 5 …”

Molecular Self-Assembly into One-Dimensional Nanotube Architectures and Exploitation of Their Functions

“…31 We recently succeeded in the selective control of polymorphism by optimizing the spacer length of wedge-shaped bolaamphiphiles, leading to the formation of a single species of organic nanotube based on an unsymmetrical monolayer membrane with a head-to-tail stacking motif. 32,55,72 A novel type of wedge-shaped glycolipids 20(n) (Chart 6) were designed and synthesized, in which ethylenediamine moiety was linked to the carboxylic terminal of 18(n). The self-assembly of a film-like solid of 20(n), which was obtained by evaporation of the DMF solution, was observed to produce one-dimensional molecular assemblies, depending on the spacer length (n).…”

“…Wedge-shaped amphiphiles are found to undergo this packing-directed self-assembly to result in nanotubes based on the unique molecular shape. 31,55 The details are shown in the Section 5.…”