Asymmetric functionalization of gold nanoparticles with oligonucleotides.

Gold nanoparticles (AuNPs) were anisotropically functionalized with two different oligonucleotide sequences using magnetic microparticles as geometric restriction templates for site-selective enzymatic extension of particle-bound oligonucleotides. The divalent linking capability of the resulting AuNPs allowed for the design and programmable assembly of discrete nanoparticle heterostructures.