Patent ID: 8220494

Claim:
A microfluidic device comprising: a first layer comprising a first side and including a first recess in said first side, said first recess comprising a curved surface; a monolithic elastomeric second layer having a first side and a second side and including a second recess in said second side, wherein the first side of the second layer is in contact with the first side of the first layer, and the first side of the second layer and the first recess define a first microfluidic channel with a transverse cross-section that comprises a curved upper surface running lengthwise along the channel, thereby forming an arched profile, a third layer comprising a planar surface, wherein the planar surface is in contact with the second side of the elastomeric second layer and, the planar surface and the second recess define a second microfluidic channel with a transverse cross-section that comprises a curved upper surface running lengthwise along the channel, thereby forming an arched profile, the second fluidic channel crossing under the first microfluidic channel, wherein the first microfluidic channel and second microfluidic channels are separated by a membrane portion of the second layer, wherein the membrane portion of the second layer is: deflectable into the first microfluidic channel in response to pressure within the second microfluidic channel and deflectable into the second microfluidic channel in response to pressure within the first microfluidic channel.