Biomedical applications of electroactive polymers and shape memory alloys

Among many kinds of polymer materials, electronic conductive material, that is polypyrrole, shows potential possibility for bio-related actuator materials. However, it may be an impediment for practical use of polypyrrole actuator that polypyrrole usually requires electrolyte solution for actuation. Our first research theme is focused on this problem solving. We have investigated many kinds of solid polymer electrolytes for the substitution of electrolyte solution. Our goals are to find the stable solid electrolyte in the air, to establish the reliable fabrication process of it and to apply it for micropump application. Besides actuators, the reduction and oxidation property of polypyrrole can be exploited for active drug delivery systems by the control of structural deformation of it. We have investigated this kind of new and bio-related possibility of polypyrrole. Shape memory alloy has another possibility in biomedical field. Due to its inherent excellent advantages as actuator materials, it can be used for micro active intravascular catheter. We have developed thin tube type bending actuator using shape memory alloy and characterized its performance by in-vivo test.