Self-Assembly of Supramolecular Nanofibers
Date : May 24, 2012 17:00 ~
Speaker : Prof. Nobuo Kimizuka (Kyushu University, Department of Chemistry and Biochemistry)
Location : Mogam Hall, Bldg.500
Date : 2012. 5 . 24, 5:00 PM
Place : Mogam Hall, Bldg.500
-Abstract-
The ability to self-assemble coordination nanoarchitectures holds promise to tailor and improve their functions for technologically important applications. To develop nanowires that self-assemble in solution, we developed a supramolecular approach that enables integration of wide-ranged molecules including inorganic, organic and bio-molecules. In this talk, we focus on the controlled fabrication of coordination nano-systems and their unique characteristics.
First, supramolecular packaging of one-dimensional coordination chains by lipid molecules give soluble nanowires which show unique characteristics not available in conventional coordination chemistry. When 1D halogen-bridged mixed valence platinum complexes are surrounded by lipid molecules, their conjugated electronic structures are tuned in response to self-assembly. Application of the lipid packaging approach linear Fe(II) 1,2,4-triazole complexes showed surprising stabilization of low spin configuration in solution. Macroscopic orientation of these nanowires are also controllable by dielectro-phoretic techniques. The combination of bottom-up self-assembly and external manipulation techniques allows us to hierarchical assembly of coordination nanowires into devices.
Second, coordination nanoparticles are self-assembled from nucleotides and lanthanide ion in water. They gave amorphous coordination networks, which revealed adaptive self-assembly with functional molecules such as dyes, porphyrins and even inorganic nanoparticles. Self-assembly of amphiphilic Tb3+ receptor complexes provides nano-interfaces which selectively convert and amplify molecular information of high energy phosphates linked by phosphoanhydride bonds into luminescence intensity changes. The unique feature and possible applications of adaptive self-assembly will be discussed.