• Efficient sequential fluid transfer in a designed centrifugal microfluidic system for DNA purification
  • Ali Fathi Ganje Lou,1,* Maryam Saadatmand,2 Nima Ahmadkhani,3
    1. Department of Chemical and Petroleum Engineering, Sharif University of Technology
    2. Department of Chemical and Petroleum Engineering, Sharif University of Technology
    3. Department of Chemical and Petroleum Engineering, Sharif University of Technology


  • Introduction: Deoxyribonucleic acid (DNA) extraction, as one of the most important steps in modern molecular diagnostics, is the process by which DNA is separated from intracellular materials like proteins, membranes, and other materials contained in the cell. Microfluidic technology enables sophisticated, time-consuming and costly experiments with minimal use of raw materials, time and cost and acceptable accuracy. The predominant advantages of centrifugal microfluidic systems are utilizing centrifugal force to generate propulsion without the need for a pump, and eliminating the need for experts to run the system. Various fluidic operations such as valving, mixing, metering, heating, and sample separation can be performed on these systems. Traditional methods of DNA extraction and purification are based on liquid-liquid extraction or solid-phase extraction technology, which are very laborious and time-consuming, and may lead to sample contamination and laboratory error.
  • Methods: In this work, the design and characterization of a completely passive lab-on-a-disk system for DNA purification were presented. The developed configuration employed passive pneumatic and inertial forces for fluidic mixing and pumping of the reagents. Modified septum valves and a siphon valve were used to conduct the fluidic sequence of the reagents. These modified septum valves reduced the leakage of the reagents into the mixing chamber compared to that of ordinary septum valves. Experiments were conducted using dyed water as representative of actual DNA extraction reagents and a successful protocol of DNA purification from lysate was obtained. Binding, washing and eluting steps were automatically performed on the proposed Lab-disk by dyed water.
  • Results: A successful protocol of DNA purification containing binding, washing and eluting steps was automatically performed on the proposed Lab-disk by using dyed water. Modified septum valves and a siphon valve were used to conduct the fluidic sequence of the reagents. These modified septum valves reduced the leakage of the reagents into the mixing chamber.
  • Conclusion: Using centrifugal microfluidic concepts, an efficient sequential fluid transfer in a lab-on-a-disk system for DNA purification is designed and a successful protocol of DNA purification is obtained using dyed water.
  • Keywords: Centrifugal microfluidics, Inertial forces, Pneumatic forces, Point of Care Systems