Authors: S.H. Parng, T.K. Shia, H.J. Yang and C.H. Kuo
Affilation: Microsystem Technology Common Laboratory, Taiwan
Pages: 625 - 628
Keywords: DNA, extraction, electrical double layer, concentration
DNA trapping was demonstrated between an electrical field across two parallel integrated electrodes on chip fabricated by the MEMS techniques. The method to release the trapped DNA molecules using reversed voltage control electrical field was investigated. We proposed the process requires only physical application of an electrical field at specified location of micro-channel network. Releasing the extracted DNA molecules can also be done by reversing the applied electrical field in an appropriately timing controlled manner. Fluid containing fixed concentration of DNA molecules is fed into this enclosed channel by syringe pump and collected at the end of it for DNA concentration analysis by Agilent 2100 bio-analyzer. The DNA concentration in the collected fluid through an electrical field is obviously reduced. It can be seen that the ionic concentration of fluid will also be an important factor in influencing the DNA trapping effectiveness by the established electrical field. The higher the ionic concentration, the better the electrical double layer (EDL) can shield the mass particles from the electrical field. We propose the studied mechanism to enhance fast DNA molecule trapping as an alternative to magnetic beads, which otherwise require more complicated and time-consuming centrifugal and chemical flushing processes.