Oligonucleotide Functionalization of Hollow Triangular Gold Silver Alloy Nanoboxes

Triangular AuAg nanoboxes functionalized with short DNA molecules (oligodeoxynucleotides, ODNs) have been prepared and their properties compared to those formed from spherical gold particles. The nanoboxes, produced from triangular silver nanoplates (TSNPs) by reduction of AuCl4– with ascorbic acid, have been further characterized by EDS mapping and HAADF-STEM measurements. Both AuAg nanoboxes and gold spherical nanoparticles were functionalized with thiol-terminated single-stranded ODNs or their complementary ODN sequences. When the complementary AuAg nanobox–ODN conjugates were combined they were observed to form networks, with the localized surface plasmon resonance (LSPR) band undergoing a red shift and a significant dampening. This assembly process was reversible upon heating and the systems showed sharp melting transitions, which could be monitored at wavelengths throughout the visible and near-IR. Finally, assemblies of the triangular nanoboxes and spherical nanoparticles have been generated.