Figure 1.

(a) The microfluidic platform is shown (left) performing epifluorescence detection (note: the lid is closed when in actual use). The principles of the sedimentation-based immunoassay (right) illustrate the ability to concentrate a bead-bound analyte while excluding contaminants; (b) The 20-channel microfluidic disc is made from lasercut PMMA and PSA layers. The close-up illustrates the channel architecture and the appearance of a used disc with the concentrated pellet of beads shown at the tip of each channel.