Disposable bio-microfluidic package with passive fluidic control

A disposable bio-microfluidic package has been developed for DNA (deoxyribonucleic acid) extraction applications. Low cost material such as PDMS (polydimethylsiloxane) is used for the encapsulation of the microfluidic chip. A network of microchannels and passive valves are formed on the PDMS by casting or soft lithography technique. They control the flow sequence of reagents in line with DNA extraction protocol. Encapsulation of the chip is done by bonding two layers PDMS substrates fabricated by acrylic mold. Plasma treatment with additional heating at 80 /spl deg/C on PDMS surface enhances the bonding strength of PDMS to chip. Passive valves with different dimensions have been fabricated and characterized for different flow rates. A microfluidic package with passive valves has been developed to control the fluidic flow in microchannels with threshold pressure.