An electrochemical system observes living cells by a chemical stimulation.

Living action of cells and tissues is due to a conversion and/or a transfer of chemical substances. In order to analyze the action of a tissues, controlled techniques is required; only a cell is stimulated in local, and then the change of chemical substances by the stimulation transfer is monitored. We are developing micro ion-release electrochemical devices to the chemical stimuli. The electrochemical ion-release device is an important tool to stimulate a cell chemically without other effects.

The ion image sensor monitors the concentration change of biogenic amines released from mast cells by a chemical stimulation. 3D images show each sensor response around a mast cell stimulated.

Ion selective electrodes (ISE) and semiconductor ion sensors (ISFET/CCD ion sensor) can measure a specific ion immediately. We have developed ISEs for polyelectrolytes and non-ionic chemicals that had been regarded as difficulty of its detection from Nernst equation. Recently, using a CCD-type ion image sensor that was developed by Professor Sawada in TUT, we are developing chemical imaging of several metal ions and biologically-important organic ions. The image sensors can monitor living cells and tissues non-invasively.

A polyelectrolyte ternary complex releases calcium ion by electrolysis.

Polyelectrolytes act as substances with unique functions. We had developed analytical methods for various synthetic and natural polyelectrolytes (chitosan, heparin, chondroitin sulfate, and polyhexanide hydrochloride, etc.) using titration, electrochemical analysis (voltammetry and potentiometry), and capillary electrophoresis. In addition the reaction of polyelectrolyte with proteins has been analyzed. Now, we develop electrochemical devices using polyelectrolytes.