Multifunctional Microfluidic Device Utilizing Unsteady Flow

This study describes experimental results for a multifunctional microfluidic device with fluid pumping, mixing and particle removal. The obstacle-type valveless micropump, micromixer and particle separator are further integrated into the proposed multifunctional device. The process for fabricating this device is simple as only 1 photo mask, 1 inductively coupled plasma (ICP) etching step and anodic glass bonding are required. This novel device was developed utilizing an unsteady flow in a microchannel induced by the piezoelectric zirconium titanate (PZT) membrane oscillation of an obstacle-type valveless micropump. Flow direction is controlled by the amplitude and frequency of power driving the vibrating membrane. The optimal operational frequency for this device is 1.0 kHz. Very high mixing (>95%) and particle removal efficiency (close to 100%) exist at the inlet region and trifurcate zone, respectively. Image processing is utilized to count the number of particles and assess removal efficiency.