Guided Lipid Tubule Formation Via Self-Assembly of Vesicles

Vesicle self-assembly offers means to construct micro structures from nano-sized building blocks. However, current vesicle self-assembly processes produce non-oriented structures that vary in shape and size. We show here that, when confined between two glass surfaces, lipid vesicles rapidly assemble into oriented tubules that can grow to be long as 13~mm under ambient conditions without externally supplied flow, temperature control, or catalyzing agents. Tubule membrane and its internal aqueous content can be manipulated by controlling the vesicle's lipid composition and aqueous entrapment. This self-assembly process opens up new pathways for generating complicated and flexible architectures for use in bio-compatible molecular and supramolecular engineering. We demonstrate these possibilities by generating encapsulated siRNA tubules, inter-digitated branching tubules, and polymerized solid tubules in a single-throughput self-assembly process.