Projects

  1. Creation of molecules
  2. Assembly of molecules
  3. Manipulation of molecules

 

Creation of molecules

Iridium complexes with cyclometalating ligands have attracted considerable attention for their potential application in electrophosphorescent organic light-emitting diodes (OLEDs). We have reported the synthesis of highly emissive iridium complexes.

Syntheses and Phosphorescent Properties of Blue Emissive Iridium Complexes with Tridentate Pyrazolyl Ligands
L. Yang, F. Okuda, K. Kobayashi, K. Nozaki, Y. Tanabe, Y. Ishii, M. Haga
Inorg. Chem, 2008, 47(16), 7154-7165

Highly Phosphorescent Iridium Complexes Containing Both Tridentate Bis(benzimidazolyl)-benzene or -pyridine and Bidentate Phenylpyridine: Synthesis, Photophysical Properties, and Theoretical Study of Ir-Bis(benzimidazolyl)benzene Complex
S. Obara, M. Itabashi, F. Okuda, S. Tamaki, Y. Tanabe, Y. Ishii, K. Nozaki, M. Haga,
Inorg. Chem. 45, 8907-8921 (2006)

[ UP ]

Assembly of molecules

The bottom-up assembly of functional nanoscale architec-ture from molecular components at the surface has attracted much interest in the advancement of nano-technology. Particularly, the chemistry of surface modi?cation by self-assembled monolayers (SAM) and layer-by-layer (LbL) growth of multilayers is highly promising to construct two-dimensional (2D) and three-dimensional (3D) chemical systems on surfaces. We have focused on the construction of redox-active LbL complex film on substrates.

Fabrication and Functions of Surface Nanomaterials Based on Multilayered or Nanoarrayed Assembly of Metal Complexes
M.Haga, K.Kobayashi,K.Terada
Coordination Chemistry Reviews (Elsevier), 251 2688-2701 (2007)

Electric Conduction Properties of Self-assembled Monolayer Films of Ru Complexes with Disulfide/Phosphonate Anchors in a Au-(Molecular Ensemble)-(Au Nanoparticle) Junction
Keiichi Terada, Katsuaki Kobayashi, Jiro Hikita, Masa-aki Haga
Chem. Lett. , 2009, 38(5), 416-417

Synthesis,electrochemical, and molecular inclusion properties of 'canopied' trinuclear ruthenium complexes with six anchoring groups on an ITO electrode
K. Terada, K. Kobayashi, M. Haga
Dalton Trans, 2008, 1-9

[ UP ]

Manipulation of molecules movie

DNA engineering, including the use of DNA microarrays, DNA computers, DNA origami and DNA-templated functional nanomaterials, is an important area of research. DNA nanowires are of particular interest because they directly contribute to the fabrication of not only DNA biochips but also the DNA-semiconductor hybrid materials used for scaffolded DNA. The high anionic charge of the DNA backbone enables the bindings of cationic metal ions to be seeded for fabrication of metallic or semiconducting nanowires. Since DNA under physiological conditions is generally folded, the extension of DNA on a surface is a prerequisite for constructing DNA nanowire devices.

We have developed a method based on the use of a Nd:YAG laser for manipulating DNA strands sequentially at a particular position and for controlling the number of DNA on the surface. A micronano bubble is formed on an Au thin film by local laser heating, which induces Marangoni convection around the bubble. The resulting Marangoni convection produces the pull-in effect common to nanomaterials such as DNA. With this method, we can for the first time manipulate single DNA on an Au-coated surface at the laser focal point. Even though we used a Nd:YAG laser for our experiments, the principle of the manipulation differs significantly from that of laser trapping with optical tweezers.

Manipulation of Single DNA Using a Micronano Bubble Formed by Local Laser Heating on an Au-coated Surface
Sho Fujii, Katsuaki Kobayashi, Katsuhiko Kanaizuka, Tetsuaki Okamoto, Shoichi Toyabe, Eiro Muneyuki, Masa-aki Haga, Chem. Lett. 2009 inpress

Fabrication of DNA Nanowires by Orthogonal Self-Assembly and DNA Intercalation on a Au Patterned Si/SiO2 Surface
K. Kobayashi, N. Tonegawa, S. Fujii, J. Hikida, H. Nozoye, K. Tsutsui, Y, Wada, M. Chiira, M. Haga
Langmuir, 2008, 24(22), 13203-13211

[ UP ]