Fig. 2. Schematic diagram of the operating principle of the micromixers and valves. (a) Compressed air is injected into the four independent air chambers below the micromixers. The membrane on the top of the air chamber was pushed by the air and rise up. When compressed air was sequentially driven into the four chambers, a vortex-like disturbance was created in the liquid above the membrane. (b) When the compressed air was injected into the air channel of the microvalves, the membrane above the air channels rose and obstructed the channels. Only arc-shaped channels allowed the valves to be fully closed.