Design and implementation of a mems based spiral channel dielectrophoretic separator for cytometry applications

Yılmaz, Gürkan
This thesis reports design and implementation of a MEMS based spiral channel dielectrophoretic separator for cytometry applications. Main objective of the thesis is to separate leukemia cells from healthy leukocytes with respect to the differences in their dielectric properties. A novel MEMS based dielectrophoretic separator with spiral channels and concentric 3D electrodes has been proposed. The proposed geometry decreased the footprint, which reduces the device cost, without degrading the separation and quantization performances. Concentric electrode geometry enables continuous electric-field application with simple voltage supplies. Theoretical explanation of the design has been presented and supported with finite element method simulations. Evolution of the design has been explained in conjunction with solutions to arising problems, chronologically. Comparisons of the proposed system with respect to the existing systems in the literature have been given. The devices are fabricated using a 3-mask process utilizing suspended parylene channel process. The experiments are realized with 1 μm and 10 μm polystyrene beads. The results show that 1 μm particles have an average speed of 4.57 μm/s with 1.06 μm/s standard deviation, and 10 μm particles have an average speed of 544 μm/s with 105 μm/s standard deviation. The speed variation coefficient for 1 μm and 10 μm beads can be calculated as 23% and 19%, respectively. The size accuracy of the device is ±10%, while the resolution is 20%, that is, particles with radii different from each other by 20% can be separated. It is worthy to note that the experimental results almost match the simulation results.


Design and implementation of A MEMS based gravimetric detector for cytometry applications
Bayraktar, Ekrem; Bayraktar, Ekrem; Department of Electrical and Electronics Engineering (2010)
This thesis reports design and implementation of a MEMS based gravimetric resonator for cytometry applications. There are mainly two objectives of this thesis; to enable in-flow analysis and to perform closed loop operation that does not require any additional processing or equipment. A novel MEMS based resonator with in-flow capabilities is proposed for detection of agents inside micro channels. High resolution of mass detection inside micro channels is planned to be succeeded with lateral motion in the mi...
Fabrication of microfluidic devices for dielectrophoretic and acoustophoretic applications using high precision machining
Soheila, Zenaili; Çetin, Barbaros; Özer, Mehmet Bülent; Süleyman, Büyükkoçak (2014-07-03)
In this study, the fabrication of microfluidic devices for dielectrophoretic and acoustophoretic based applications with high-precision CNC machining has been presented. For both devices, molds out of stainless steel have been fabricated, and polymer molding is implemented. For dielectrophoretic device, the metal electrodes have been fabricated using high-precision machining and embedded into the device during the molding process. For acoustophoretic device, piezoelectric slides have been embedded into the ...
A stochastic disassembly line balancing problem with hazardous tasks
Göksoy Kalaycılar, Eda; Batun, Sakine; Department of Industrial Engineering (2020-11)
In this thesis, we study a Stochastic Disassembly Line Balancing Problem (SDLBP) with hazardous tasks. We define success and failure events for each hazardous task and describe several scenarios over all hazardous tasks. Our aim is to maximize expected profit over all scenarios. We construct mathematical model with one, two and three hazardous tasks. Then, general formulation both in nonlinear and linear form is studied. We test the performance of the model on randomly generated data using the networks take...
Development of an intelligent model prediction controller for autonomous helicopters
Kubali, Şevket Eser; Yavrucuk, İlkay; Department of Aerospace Engineering (2016)
In this thesis, a new PID gain update law using linear least squares regression is introduced as an adaptive control method for autonomous helicopters. In addition, future prediction analyses are conducted for error dynamics of the closed loop system using recursive linear least squares regression. Combining these two concepts with classical PID controller, an intelligent PID controller is obtained. On the other hand, using PID controllers, a flight controller with three control loops is developed to demons...
Design and implementation of low leakage MEMS microvalves
Yıldırım, Ender; Külah, Haluk; Arıkan, Mehmet Ali Sahir; Department of Mechanical Engineering (2011)
This thesis presents analysis, design, implementation, and testing of electrostatically actuated MEMS microvalves. The microvalves are specifically designed for lab-on-a-chip applications to achieve leakage ratios below 0.1 at pressure levels in the order of 101 kPa. For this purpose, two different microvalves are presented in the study. In the proposed designs, electrostatic actuation scheme is utilized to operate the microvalves in normally open and normally closed modes. Characterization of normally open...
Citation Formats
G. Yılmaz, “Design and implementation of a mems based spiral channel dielectrophoretic separator for cytometry applications,” M.S. - Master of Science, Middle East Technical University, 2010.