Hierarchical AgNR@Cys@AuNPs Helical Core–Satellite Nanostructure: Shape-Dependent Assembly and Chiroptical Response

Abstract

Helical core–satellite nanoarchitectures of AgNR@Cys@AuNPs have been successfully fabricated by self-assembly of Ag nanorods and Au nanoparticles, using l- and d-cysteine as bridging molecules, respectively. The chirality of the nanoarchitectures is confirmed by circular dichroism spectroscopy, and the results suggest that the chirality of nanoarchitectures relicates the l- and d-conformation of cysteine. The absorption peak of AgNR@Cys@AuNPs nanoarchitectures on the circular dichroism spectra shows a gradual red-shift with increasing cysteine concentration. The helical arrangement of Au nanoparticles in the nanoarchitectures is strongly dependent on the shape of Ag backbones and the cysteine concentration.