Fabrication of ordered metallic and magnetic heterostructured DNA—Nanoparticle hybrids

Here we provide a method based on enzymatically catalyzed reactions to cleave and ligate DNA molecules coated with nanoparticles to fabricate multi-component structures. This is done by simultaneously digesting two solutions of nanoparticle coated DNA, one with iron oxide particles the other gold particles, which yields short DNA fragments with complementary single stranded overhangs. When added together and re-attached using ligase enzymes multi-component nanoparticle coated structures are formed providing a novel method to fabricate complicated nanoparticle arrangements from the bottom up. We evaluated the fabrication by characterizing the samples with gel electrophoresis and magnetic force microscopy (MFM). The electrophoresis provides proof that the coated DNA molecules were digested with restriction enzymes and ligated by the T4 ligase enzymes. MFM experiments allow us to visualize the multi-component strands and analyze the magnetic versus metallic segments.