Patent ID: 7837946

Claim:
A microfluidic device comprising: a first microfluidic flow channel, a plurality of second microfluidic flow channels branching from said first microfluidic flow channel, wherein each said second microfluidic flow channel terminates at a terminal wall and comprises a reaction site proximal to the terminal wall; a plurality of microfluidic control channels; a plurality of valves, wherein said valves are under common control and are coordinately closed or opened; wherein said valves are configured so that, when closed, each valve isolates said reaction site from other reaction sites; wherein each said valve comprises a deflectable elastomeric membrane separating a microfluidic flow channel and a microfluidic control channel associated with the valve, wherein said valve is closed by pressurization of the microfluidic control channel associated with the valve, and wherein the elastomeric membrane is formed from an elastomeric material having a Young's modulus in the range 50 Pa to 10 MPa; and wherein the density of reaction sites is at least 500 sites/cm 2 .