title: Helical rosette nanotubes with tunable stability and hierarchy.
abstract: The design of nanostructured materials with tunable dimensions and properties that maintain their structural integrity under physiological conditions is a major challenge in biomedical engineering and nanomedicine. Helical rosette nanotubes (HRN) are a new class of materials produced through a hierarchical self-assembly process of low molecular weight synthetic organic modules in water. Here, we describe a synthetic strategy to tune their stability and hierarchy by preorganization of the self-assembling units, control of net charge per unit of nanotube surface area, amphiphilicity, and number of H-bonds per self-assembling module, and through peripheral steric (de)compression. Using these criteria, HRNs with tunable stability and hierarchical architecture were produced from self-assembling modules that (a) persist as individual molecules in solution, (b) self-assemble into HRN but denature at high temperature (<85 degrees C), (c) self-assemble into HRN whose structural integrity persists even in boiling water (>95 degrees C), and (d) self-assemble into well-dispersed short nanotubes, long nanotubes, ribbons, or superhelices. Given the biocompatibility, synthetic accessibility, and chemical and physical tunability of these materials, numerous applications in biomedical engineering, materials science, and nanoscience and technology are envisioned.
authors.affiliation: National Institute for Nanotechnology (NINT-NRC), Department of Chemistry, University of Alberta, ECERF 9107-116 Street, Edmonton, Alberta T6G 2V4, Canada.
authors.forename: Jesus G
authors.initials: JG
authors.lastname: Moralez
authors.forename: Jose
authors.initials: J
authors.lastname: Raez
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamazaki
authors.forename: R Kishan
authors.initials: RK
authors.lastname: Motkuri
authors.forename: Andriy
authors.initials: A
authors.lastname: Kovalenko
authors.forename: Hicham
authors.initials: H
authors.lastname: Fenniri