Molecular docking and aberration-corrected STEM of palladium nanoparticles on viral templates

Abstract

Viral templates are highly versatile biotemplates used for the synthesis of nanostructured materials. Rotavirus VP6 self-assembles into nanotubular hollow structures with well-defined diameters and variable lengths, serving as a nucleic acid-free biotemplate to synthesize metal nanoparticles of controlled size, shape, and orientation. Molecular docking simulations show that exposed residues (H173-S240-D242 and N200-N310) of VP6 have the ability to specifically bind Pd(II) ions, which serve as nucleation sites for the growth and stabilization of palladium nanoclusters. Using VP6 nanotubes as biotemplates allows for obtaining small Pd particles of 1–5 nm in diameter. Advanced electron microscopy imaging and characterization through ultra-high-resolution field-emission scanning electron microscopy (UHR-FE-SEM) and spherical aberration-corrected scanning transmission electron microscopy (Cs-STEM) at a low voltage dose (80 kV) reveals, with high spatial resolution, the structure of Pd nanoparticles attached to the macromolecular biotemplates.