Lens-free imaging of DEP manipulated cancer cells

Aslan, Mahmut Kamil
Dielectrophoresis (DEP) method is based on manipulating dielectric particles under nonuniform electric field according to their unique electrical properties. With the developments in both MEMS and microfluidics technology, DEP becomes promising technique in cell manipulation. Main advantages of the DEP can be listed as: label free operation, simple implementation and cost effectiveness. However, most of the systems implementing DEP method to manipulate cells, includes microscope, computer and signal generator which are not easily available and limiting portability. Lens-free CMOS imaging is an alternative technique in cell quantification by offering cost effectiveness, easy-to-use operation and portability. In this thesis, a lab-on-a-chip (LOC) system integrating the DEP technique with lens-free CMOS imaging to quantify manipulated cancer cells is developed. In the design phase of the system, different DEP device designs having various electrode width and interelectrode gaps are proposed. DEP devices are energized with a portable signal generator circuitry. Additionally, CMOS image sensor is operated with a smartphone for processing CMOS image data for cell quantification in stand-alone manner. Finally, mechanical integration of the LOC system is completed with 3D printed holders. Experimental results shows both functionality of the DEP device designs under different flow rates (0-3 µL/min) and counting accuracy of the CMOS imager integrated with the DEP devices. The counting accuracy of the system is above 90%. As a future development, the system performance can be increased utilizing different image reconstruction techniques for achieving better resolution. Moreover, DEP designs can be revised to selectively capture rare cells from heterogeneous cell solutions.
Citation Formats
M. K. Aslan, “Lens-free imaging of DEP manipulated cancer cells,” M.S. - Master of Science, Middle East Technical University, 2017.