Size-Controlled Ni Nanocrystal Growth on Peptide Nanotubes and Their Magnetic Properties


  • This work was supported by the U.S. Department of Energy (DE-FG-02-01ER45935). I.B and L.Y thank Prof. Karl Fath at the Core Facilities for Imaging, Cell, and Molecular Biology in the Biology Department at Queens College—CUNY for the use of the transmission electron microscope. M.S. thanks Prof. C. A. Ross at MIT for the use of the AGM for magnetization measurements.


In nature, peptides bind metals reproducibly and selectively via specific amino acid sequences, producing nanocrystals in controlled sizes and morphologies. A novel method of growing uniform nanocrystals directly on biological nanotubes by immobilizing synthetic Ni-mineralizing peptides on the nanotubes is reported (see Figure). Control of the Ni nanocrystal size is a function of pH, enabling tunability of magnetic properties in the resulting nanotube.