Spiral microchannels on a CD for DNA hybridizations

Microfluidic devices on CD have benefited from the advantages of centrifugal pumping. To date, only channels in the radial direction have been used in these devices. In this work, we have designed numerous spiral channels on CD. Through a two-step assembly process, these spiral channels intersect with pre-immobilized radial DNA probe line to form an array of DNA that covers the whole CD surface. In our experiments, 96 radial channels were used for the first step of DNA probe immobilizations. Then, 96 spiral channels were used for the second step of hydrodynamic DNA sample hybridizations. The 96 × 96 intersections between the spiral channels and radial lines of DNA probes created a multi-sample–multi-probe array on a CD.