Hexagonally ordered ammonium lithocholate self-assembled nanotubes with highly monodisperse sections

Self-assembled nanotubes and helical aggregates are ubiquitous in nature, making them attractive targets for nanometer-scale fabrication. The effect of counterions (NH4+ vs. Na+) on the formation of self-assembled ammonium lithocholate (NH4LC) nanotubes in alkaline aqueous solutions is reported. A spectacular enhancement of the cross-sectional monodispersity of the sections is found. In addition, the tubes exhibit a strikingly well-ordered hexagonal distribution (see figure) with a moderate increase in temperature to 40-50 degrees C.