Peptide amphiphile nanofibers template and catalyze silica nanotube formation.

Hollow silica nanotubes with tunable dimensions have been synthesized by condensation of tetraethoxysilane (TEOS) on peptide-amphiphile nanofiber templates followed by calcination. Peptide-amphiphile nanofibers direct silica mineralization by providing nucleation sites and catalyze silica polymerization at their surface. The catalytic activities of peptide-amphiphiles containing lysine, histidine, or glutamic acid were compared and only peptide amphiphiles containing lysine or histidine were found to be good catalytic templates. Depending on the reaction conditions, and the size of the PA assembler, the nanotube wall thickness could be varied between 5 and 9 nm.