Enhancement of DNA detection with magnetofluidics
Lim, Chee Dak
Date of Issue2017-05-09
School of Mechanical and Aerospace Engineering
Microfluidic is a technology which allows fluid to be studied on a micro scale. This technology development has advanced and is widely used for different applications in the medical field. Magnetofluidic is a microfluidic method which involves using magnet and ferrofluid to manipulate fluid. Therefore, this brings us to enhance the detection of DNA using magnetofluidic. In this project, experiments are conducted by mixing DNA sample with ferrofluid and subject it to magnetic field by cubic magnets to achieve a separation phenomenon. The DNA sample is prepared by polymerase chain reaction (PCR) using pUC19 model DNA. Gel electrophoresis and fluorescence imaging is used to check on the progress of the PCR. Purification of DNA sample is to remove impurities which give the final DNA concentration of 30-35 ng/ µl. A magnet arrangement is determined to enhance the DNA detection. Hydrophilic coating solution was found to be a factor to reduce bubbles trapped in chip channel after treatment. This project also investigate the volume ratio of DNA sample to ferrofluid using polymethyl methacrylate (PMMA) chip of depth 50 µm and polydimethylsiloxane (PDMS) chip of depth 100 µm. Intensity imaging is carried out using ImageJ and result show the intensity of the collected DNA increases as the DNA sample concentration increases. Our experiments conclude that PDMS chip are preferred over PMMA chip due to machining defects and the correct concentration of ferrofluid is able to enhance the DNA detection. For further study, magnet holder setups were designed to explore more magnet arrangements and a lysis holder was designed for mechanical cell lysis to obtain actual DNA from cells. The design of the chip channel can be revised to enhance DNA detection.
Final Year Project (FYP)
Nanyang Technological University