Molecular Recognition & Sensors

Using synthetic molecules, we study the mutual recognition of molecules or ions and apply them to develop molecular sensors that detect various ions and biomolecules.

Functional foldamers

Foldamers are synthetic molecules that fold into an order array as seen in the secondary structures (helix, sheet, or turn) of proteins. The ordered structures can be induced by non-covalent interactions between internal segments, substrate binding, metal coordination, and/or solvophobic (hydrophobic) interactions. We have been focused on the development of functional foldamers based on indoles, indolocarbazole and phenylurea which folds into a helical structure to generate an internal tubular cavity, thus functioning as molecular receptors, sensors, switches, etc. We are also investigating the synthesis and characterization of hybrid molecules in which the number of the bioactive components can be systematically varied and the geometrical array be precisely controlled.

Tramsmembrane Carriers, Channel & Pores

We develop synthetic molecules that can transport polar organic molecules and ions from lipid membranes or cell membranes. In particular, it develops chlorine ion transporters and molecules that form channels through which water or carbohydrates can move, and applies them to develop new purification, separation and detection methods.

(Supra) Molecular Machines and Switches

Molecules and supramolecules may exist in the two or more different states of the conformations or binding modes that can be reversibly controlled by external stimulations; light, electrochemical and electronic methods, pH, and other chemical species. To develop molecular machines, actuators, switches, etc, we have studied interlocked supermolecules such as pseudorotaxanes and rotaxanes with reversible transition metal? ligand bonds. More recently, we are working on the foldamers that display reversible conformational changes between zigzag expansion and helical contraction by an anion.