Measurements of blood coagulation using digital micro-fluidic system based on surface acoustic wave devices

A digital microfluidic system (DMFS) is realized using a surface acoustic wave (SAW) device. In this paper, the DMFS was applied to blood coagulation monitor. The DMFS used consisted of sensor plate/liquid layer/piezoelectric substrate. One pair of interdigitated electrode (IDE) was fabricated on the sensor plate. Electrical impedance change due to the blood coagulation was monitored on the IDE. For monitoring coagulation, temperature of the sample must keep at 37 °C. The liquid temperature can be controlled by the SAW. The optimum input signal condition was experimentally found and the blood coagulation was monitored. Using the DMFS, reproducible measurements of the blood coagulation were possible.