Tools for the development of electrochemical sensors: an EQCM flow cell with flow focusing

A novel flow cell capable of improving piezoelectric response in system combining Electrochemical Quartz Crystal Microbalance (EQCM) and Flow Injection Analysis is presented. The original design of flow cell modified in shape and position of ports compared to other models for QCM is proposed. Electrochemical and viscoelastic experiments showed focusing of the sample in the central zone between ports and a remarkable enhancement of mass sensitivity compared to Sauerbrey value. Enhancement of mass sensitivity may allow piezoelectric device to be applied to the same concentration range of electrochemical ones and may be used as a tool to develop electrochemical sensors.