Fluidic devices and methods using them

A laminated microfluidic device comprising:

• an internal microchannel formed from laminating individual layers of the laminated microfluidic device to each other,
• the laminated microfluidic device further comprising:
• a first port,
• a second port,
• a third port, and
• a fourth port each fluidically coupled to the internal microchannel,
• wherein each of the first port, the second port, the third port and the fourth port permits fluid flow into and out of the internal microchannel of the laminated microfluidic device,
• wherein the laminated microfluidic device is configured to permit flow of sample into the laminated microfluidic device through the first port,
• wherein the laminated microfluidic device is configured to fluidically couple to an external pressure source through the second port to provide pressure within the internal microchannel of the laminated microfluidic device, and
• wherein the laminated microfluidic device is configured to permit the flow of the sample to a first component fluidically coupled to the third port and to a second component fluidically coupled to the fourth port depending on the pressure within the internal microchannel of the laminated microfluidic device.