DNA Origami Metallized Site Specifically to Form Electrically Conductive Nanowires

Abstract

DNA origami is a promising tool for use as a template in the design and fabrication of nanoscale structures. The ability to engineer selected staple strands on a DNA origami structure provides a high density of addressable locations across the structure. Here we report a method using site-specific attachment of gold nanoparticles to modified staple strands and subsequent metallization to fabricate conductive wires from DNA origami templates. We have modified DNA origami structures by lengthening each staple strand in select regions with a 10-base nucleotide sequence and have attached DNA-modified gold nanoparticles to the lengthened staple strands via complementary base-pairing. The high density of extended staple strands allowed the gold nanoparticles to pack tightly in the modified regions of the DNA origami, where the measured median gap size between neighboring particles was 4.1 nm. Gold metallization processes were optimized so that the attached gold nanoparticles grew until gaps between particles were filled and uniform continuous nanowires were formed. Finally, electron beam lithography was used to pattern electrodes in order to measure the electrical conductivity of metallized DNA origami, which showed an average resistance of 2.4 kΩ per metallized structure.

Metallized DNA nanolithography for encoding and transferring spatial information for graphene patterning

“…DNA nanostructures can be used to expand the morphological and functional diversity of other nanomaterials. For example, DNA nanostructures can template the positioning of nanoparticles and carbon nanotubes [29][30][31][32][33] and they can also be functionalized into metallic nanostructures [34][35][36][37][38][39][40] . However, the transfer of spatial information to other 2D materials remains unexplored.…”

“…However, the transfer of spatial information to other 2D materials remains unexplored. Metallization produces nanowires and particles composed of disconnected grains, which decrease the conductivity [34][35][36][37][38][39][40] . In this way, DNA metallization is limited in its ability to construct nanoelectronic devices 40 .…”

“…Metallization produces nanowires and particles composed of disconnected grains, which decrease the conductivity [34][35][36][37][38][39][40] . In this way, DNA metallization is limited in its ability to construct nanoelectronic devices 40 . DNA nanostructures have also been used as shadow masks for metal deposition 41 and SiO 2 etching [42][43][44] .…”

DNA Origami as a Tool to Design Asymmetric Gold Nanostructures

“…Individual staples can be extended with sticky ends (additional sequences) that protrude on the surfaceand allow the use of DNA origami as a template to assemble nanoparticles. Using the covalent bond between gold and sulfur, functionalized gold nanoparticles with complementary sequences can then hybridize with the sticky ends (Mirkin, Letsinger, Mucic & Storhoff, 1996;Nuzzo & Allara, 1983;Dubois & Nuzzo, 1992;Herne &Tarlov, 1997;Yang, Yau & Chan, 1998;Bain & Whitesides, 1989;Hickman et al, 1992;Storhoff et al, 2000;Storhoff, Elghanian, Mucic, Mirkin, & Letsinger, 1998;Jin, Wu, Li, Mirkin, & Schatz, 2003;Pearson et al, 2012). This process then attaches the gold nanoparticles onto the origami surface.…”

3D DNA origami designed with caDNAno

“…This simple, "one-pot" method uses several hundred staple strands to direct the folding of a long, single scaffold strand of DNA into pre-defined shapes [10]. Applications have emerged based on DNA origami, such as using it to arrange metal nanoparticles [13][14][15], to design and construct detergent-resistant liquid crystal DNA-nanotubes that can in turn be used to induce weak alignment of membrane proteins [16], to produce label-free RNA hybridization probes [17], and for the self-assembly of carbon nanotubes into two-dimensional geometries [18].Here, we describe the design of a 3D origami structure, which resembles a roller, using the open source software package, caDNAno, constrained to the honeycomb framework [12]. We analyze and characterize the structure obtained using gel electrophoresis, atomic force microscopy (AFM) and transmission electron microscopy (TEM).…”