Abstract: A microfluidic platform for investigating cell-based interactions with a chip base is made of a suitable plastics material with the appropriate optical properties. The chip base has a plurality of ports in fluid communication with a microfluidic channel for containing a culture medium in which cells are held. A gas permeable laminate is bonded to a bottom surface of the chip base. Each port has an internal inlet, connecting the port with the microfluidic channel, and a trough for containing a small reservoir of culture medium fluid adjacent to the inlet. When in use, culture medium can be aspirated from the microfluidic channel via the trough rather than directly via the internal inlet.