Synthesis of Bimetallic PdAg Nanoparticles through an Oligomerization- Controlled Biomineralization Peptide

Abstract

Peptide – mediated biomineralization is an emerging and promising biomimetic approach for the synthesis of nanomaterials. This nature – inspired technique of producing inorganic nanostructures depends on the biomineralization peptide to control the shape and morphology of the prevailing inorganic nanostructure. One of the challenges in peptide – mediated biomineralization is controlling the 3D arrangement and orientation of the peptide. Recently, we have developed a peptide platform that can specify and direct the geometric arrangement and spatial orientation of the biomineralization peptide. The peptide platform is composed of two segments: a metal binding sequence, and the tetramerization domain of the tumor suppressor p53 protein, which acts as the oligomerization control element. The resulting fusion peptide exhibits a spatially – fixed and well – controlled assembly of the palladium binding sequence. This present study demonstrates the utility and efficacy of this peptide platform to bimetallic materials. Monodispersed 5 nm bimetallic PdAg nanoparticles were synthesized using the oligomerization – controlled biomineralization peptide. The synthesis was carried out in an aqueous environment, void of harsh reagents. When other fusion biomineralization peptides were used to synthesize bimetallic PdAg nanoparticles, less ordered nanoparticles were yielded. The results highlight the importance of controlled assembly on bimetallic nanoparticle formation through biomineralization. The presented method offers a straightforward manner of creating monodispersed and extremely small nanoparticles, which are useful in a wide array of applications.