Genomic DNA extraction from whole blood using a digital microfluidic (DMF) platform with magnetic beads

DNA extraction is one of the most essential steps in nucleic acid testing, which usually requires a series of reagent mixing, centrifugal separations, and manual operations. While microfluidic devices have shown their capability in point-of-care applications, some of them face the challenge in on-chip sample preparation, such as DNA extraction from blood samples, prior to the diagnosis. Although digital microfluidic (DMF) eliminates the need of complicated fluidic actuation components and draws great attentions as a promising Lab-on-a-Chip platform, its capability in DNA extraction has been limitedly shown. Herein, we develop a protocol on a DMF platform for DNA extraction. As the protocol contains blood, magnetic beads, a variety of liquids, and complicated steps, it was implemented in a sequence of droplet operations with our proposed washing/droplet-separation strategy. Our on-chip extraction protocol was conducted with room-temperature incubations and much less washing cycles. The results were confirmed by using SYBR-Green dye staining and gel electrophoresis. Therefore, the DMF device was shown to permit on-chip DNA extraction with fewer sample/reagent consumption and shorter operation time.