Synthesis of self-assembled noble metal nanoparticle chains using amyloid fibrils of lysozyme as templates

Abstract

We reported a facile method for preparing self-assembled noble metal nanoparticle chains by using lysozyme amyloid fibrils as a biotemplate in an aqueous environment. The nanoparticle chains of gold (AuNPCs), palladium (PdNPCs), platinum (PtNPCs) and rhodium (RhNPCs), which are lysozyme fibrils coated by gold, palladium, platinum and rhodium nanoparticles, can be fabricated by simply reducing the corresponding metal salt precursors using NaBH4. Under the same molar ratio between salt precursors and fibrils, two types of morphologies of highyield AuNPCs (thin- and thick- AuNPCs) were synthesized as a result of adjusting the fibrosis time and temperature in the final stage. Abundant PdNPCs with a length of several micrometres intertwisted with each other to form PdNPC networks. The growth of RhNPCs started from the inner surface of the fibrils and gradually spread to the whole fibre as superabundant rhodium nanoparticles (RhNPs) bound to the fibrils. Finally, PtNPCs at different growing periods were presented. The nanostructures were investigated by transmission electron microscope, UV-visible spectroscopy, fluorescence spectroscopy, energy-dispersive X-ray spectroscopy and atomic force microscope.