A Microfabricated Rotary Pump

Because microfluidic devices operate at low Reynolds number, many fluidic operations are limited by diffusion. We have developed a microfabricated rotary pump and demonstrated that active mixing can be used to overcome the slow diffusion process in two applications. First, we showed that mixing of reagents could be efficiently accomplished for objects of a wide range of diffusion constants. Second, we showed how reaction kinetics of a surface-binding assay can be enhanced by nearly two orders of magnitude.