Applications of EWOD Systems for DNA Reaction and Analysis

Abstract A digital microfluidic system based on electrowetting-on-dielectric (EWOD) technology has attracted considerable attention because of its promising potential in biological, biochemical and biomedical applications. The digital microfluidic (EWOD) system enables a discrete droplet to be manipulated through reconfig-urable paths or channels defined by electrode actuation. Minute sample and reagent volume, precise droplet control, low energy consumption, low cost, rapid analysis, portablility for point-of-care diagnosis, flexibility for integrating with detector, multiple-step and simultaneous reaction processes are all advantages of EWOD system. Thus, it has become a promising and popular tool for bio-applications such as cell assays, proteomics, enzyme assays, immunoassays, DNA extraction, DNA repair and DNA amplification. In DNA-based applications, ordinarily, the DNA replication (e.g., DNA amplification) is necessary. Among the DNA replication techniques, Polymerase Chain Reaction (PCR) because of its simplicity and cost-effectiveness is the most common laboratory technique. Therefore, the development of EWOD-based microfluidic PCR system combined with other novel techniques for DNA amplification or DNA-based assays has extensively been reported. In this paper, the recent developments and studies of EWOD microfluidic system for DNA-based applications published in the last five years have been reviewed.