Controlling the spatial organization of objects at the nanoscale is a key challenge in enabling their technological application1–3. Biomolecular assemblies are attractive nanostructures owing to their biocompatibility, straightforward chemical modifiability, inherent molecular recognition properties and their availability for bottom-up fabrication4–16. Aromatic peptide nanotubes are self-assembled nanostructures with unique physical and chemical stability and remarkable mechanical rigidity14–16. Their application in the fabrication of metallic nanowires and in the improvement of the sensitivity of electrochemical biosensors have already been demonstrated14–17. Here we show the formation of a vertically aligned nanoforest by axial unidirectional growth of a dense array of these peptide tubes. We also achieved horizontal alignment of the tubes through noncovalent coating of the tubes with a ferrofluid and the application of an external magnetic field. Taken together, our results demonstrate the ability to form a two-dimensional dense array of nanotube assemblies with either vertical or horizontal patterns.
Bibliographical noteFunding Information:
The authors acknowledge support from the Israel Science Foundation (the F.I.R.S.T program). We thank members of the Gazit Laboratory for helpful discussions. M.R. gratefully acknowledges the support of the Clore Foundation Scholars Programme and the Dan David Scholarship Award. The authors would like to thank E. Wachtel for the XRD analysis, S. Wolf for the electron diffraction analysis, and M. Pauzner for graphical assistance. Correspondence and requests for materials should be addressed to E.G. Supplementary information accompanies this paper on www.nature.com/naturenanotechnology.