Light-induced disassembly of self-assembled vesicle-capped nanotubes observed in real time

Abstract

Molecular self-assembly is the basis for the formation of numerous artificial nanostructures. The self-organization of peptides, amphiphilic molecules composed of fused benzene rings and other functional molecules into nanotubes is of particular interest. However, the design of dynamic, complex self-organized systems that are responsive to external stimuli remains a significant challenge. Here, we report self-assembled, vesicle-capped nanotubes that can be selectively disassembled by irradiation. The walls of the nanotubes are 3-nm-thick bilayers and are made from amphiphilic molecules with two hydrophobic legs that interdigitate when the molecules self-assemble into bilayers. In the presence of phospholipids, a phase separation between the phospholipids and the amphiphilic molecules creates nanotubes, which are end-capped by vesicles that can be chemically altered or removed and reattached without affecting the nanotubes. The presence of a photoswitchable and fluorescent core in the amphiphilic molecules allows fast and highly controlled disassembly of the nanotubes on irradiation, and distinct disassembly processes can be observed in real time using fluorescence microscopy.