Three-way microvalve for blood flow control in medical micro total analysis systems (/spl mu/TAS)

In order to realize a medical micro total analysis system in practical use, a partly disposable 3-way microvalve was developed. The separate channel structure and pneumatic actuation are employed considering the problems of whole blood handling. It has the advantages of easy assembly, large on/off flow ratio (about 10/sup 4/), no bubble problem, low cost due to the partly disposable structure and perfect process matching to micro chemical sensors (amperometric sensors or ISFETs).