Nanoscale Assembly Using DNA and Electromagnetic Fields

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto. fi Author Antti-Pekka Eskelinen Name of the doctoral dissertation Nanoscale Assembly Using DNA and Electromagnetic Fields Publisher School of Science Unit Department of Applied Physics Series Aalto University publication series DOCTORAL DISSERTATIONS 139/2013 Field of research Nanotechnology Manuscript submitted 9 September 2013 Date of the defence 4 October 2013 Permission to publish granted (date) 30 August 2013 Language English Monograph Article dissertation (summary + original articles) Abstract In this work we demonstrate the control of nanoparticles and nanostructures with the help of the DNA origami method and dielectrophoresis. DNA nanotechnology is a subfield of nanotechnology where DNA is used as a construction material. The DNA origami method is a recent development in the field which enables the assembly of nanoparticles with nanometer scale accuracy through self-assembly. Here we take advantage of the method for efficient deposition and alignment of single-walled carbon nanotubes (SWCNTs). Especially the alignment of SWCNTs on substrates has been a major challenge for commercialization of SWCNT based devices, to which our approach could offer a potential solution. As an example, a crossed carbon nanotube junction, a basic geometry for a carbon nanotube transistor, is constructed. The high yields of assembled structures as well as correct alignment of SWCNTs are verified with atomic force microscopy. The DNA origami method is used also for assembling a bow-tie antenna configuration from silver nanoparticles. The optical response of the system is based on the hybridization of the individual nanoparticle surface plasmon resonance modes. The formation of the structures is verified with transmission electron microscopy and complemented with agarose gel electrophoresis. The configuration could have potential use as an optical DNA sensor. The sensor performance is investigated with finite-difference time-domain numerical simulations. In addition to assembling nanoparticles, control over the DNA origami structure itself is demonstrated with dendrons and external trigger signals. Efficient control over the structure formation is investigated with atomic force microscopy, agarose gel electrophoresis and dynamic light scattering experiments. The external trigger signals can be chosen by choosing the dendron structure. We demonstrate our concept with dendrons which can be triggered either with UV-radiation or with a mild reducing agent such as dithiothretoil. Dielectrophoresis is an electromechanical technique for manipulating micro-and nanoparticles. Here the method is used for developing a new nanoimprint lithographic technique named field-induced nanoimprint lithography. In this technique nanoelectrodes are used for producing dielectrophoretically a pattern of nanoparticles on a re-usable master stamp, which is then used for transferring the nanoparticle pattern on a target substrate by mechanical contact. Dielectrophoresis is also used for producing chains of gold nanoparticles between nanoand microelectrodes. The chains are investigated for sensing purposes with impedance studies.In this work we demonstrate the control of nanoparticles and nanostructures with the help of the DNA origami method and dielectrophoresis. DNA nanotechnology is a subfield of nanotechnology where DNA is used as a construction material. The DNA origami method is a recent development in the field which enables the assembly of nanoparticles with nanometer scale accuracy through self-assembly. Here we take advantage of the method for efficient deposition and alignment of single-walled carbon nanotubes (SWCNTs). Especially the alignment of SWCNTs on substrates has been a major challenge for commercialization of SWCNT based devices, to which our approach could offer a potential solution. As an example, a crossed carbon nanotube junction, a basic geometry for a carbon nanotube transistor, is constructed. The high yields of assembled structures as well as correct alignment of SWCNTs are verified with atomic force microscopy. The DNA origami method is used also for assembling a bow-tie antenna configuration from silver nanoparticles. The optical response of the system is based on the hybridization of the individual nanoparticle surface plasmon resonance modes. The formation of the structures is verified with transmission electron microscopy and complemented with agarose gel electrophoresis. The configuration could have potential use as an optical DNA sensor. The sensor performance is investigated with finite-difference time-domain numerical simulations. In addition to assembling nanoparticles, control over the DNA origami structure itself is demonstrated with dendrons and external trigger signals. Efficient control over the structure formation is investigated with atomic force microscopy, agarose gel electrophoresis and dynamic light scattering experiments. The external trigger signals can be chosen by choosing the dendron structure. We demonstrate our concept with dendrons which can be triggered either with UV-radiation or with a mild reducing agent such as dithiothretoil. Dielectrophoresis is an electromechanical technique for manipulating micro-and nanoparticles. Here the method is used for developing a new nanoimprint lithographic technique named field-induced nanoimprint lithography. In this technique nanoelectrodes are used for producing dielectrophoretically a pattern of nanoparticles on a re-usable master stamp, which is then used for transferring the nanoparticle pattern on a target substrate by mechanical contact. Dielectrophoresis is also used for producing chains of gold nanoparticles between nanoand microelectrodes. The chains are investigated for sensing purposes with impedance studies.