Fluid control

A self-contained, dry, planar microfluidic cartridge for use in conducting one or more assay(s) on a liquid sample, the microfluidic cartridge comprising:

• a sample input port for receiving the liquid sample, the sample input port connected to at least one microfluidic channel at a first end of said microfluidic channel, wherein each/said microfluidic channel(s) comprises one or more reagents deposited therein for use in conducting the assay and a detection zone for use in detecting any analyte which may be present in the sample or analyte reaction product thereof;
• and
• each/said microfluidic channel(s) is further fluidly connected to compressible gas-filled chamber disposed at a second end of each/said microfluidic channel(s) downstream from each/said deposited reagents and detection zone, wherein each/said gas-filled chamber lacks any valve or port that communicates with the outside of the strip, and wherein the self-contained dry planar microfluidic cartridge does not contain liquid prior to the application of a sample and comprises three resilient planar layers, which are sandwiched together to define each/said microfluidic channel(s) and each/said gas-filled chamber(s) and wherein said gas-filled chamber(s) are configured to be compressed, thereby causing the gas-filled chamber to be deformed and gas to be expelled from the gas-filled chamber(s) and upon decompressing the gas-filled chamber(s), the gas-filled chamber(s) are configured to return to its non-deformed state, and whereby gas is configured to be drawn back into the gas-filled chamber(s), wherein said compression and decompression in turn is configured to cause reciprocal movement of the liquid sample within said/each microfluidic channel.