A Dynamic Microarray with Pneumatic Valves for Selective Trapping and Releasing of Microbeads

This paper describes a dynamic microarray device with pneumatic valves for trapping and releasing microbeads selectively. We fabricated thin membranes of polydimethylsiloxane (PDMS) inside our conventional dynamic microfluidic device. The membrane works as a pneumatically driven valve that changes the fluidic resistance, which ultimately determines the modes of the device: trapping, passing, or releasing. Using this device, we successfully controlled these three modes by using 100 ?m polystyrene microbeads. Moreover, we succeeded in arraying two different types of microbeads alternately in a single device by selectively activating and deactivating the pneumatic valves.