الفهرس 
صفحة العنوانOnly 14 pages are availabe for public view
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Abstract
The characterization and manipulation techniques of biological particles became the focus of scientists in various fields such as engineering, chemistry, medicine, physics, and biology. A lab-on-a-chip is a class of device that integrates and automates multiple laboratory techniques into a system that fits on a chip up to a maximum of a few square centimetres in size. LOC reduces area, power consumption, and testing time.
The electrical characteristics and dielectric properties play important roles in the characterization and separation of biological particles, such as biological cells and micro-organisms. The dielectrophoresis (DEP) is a phenomenon in which a non-uniform electric field generates a force on neutral but polarizable particles. DEP is preferred for separation and manipulation of biological particles due to several advantages i.e., its high sensitivity in the detection of cells that have different dielectric properties.
In this study, a Biochip based on DEP is designed, simulated, and fabricated to identify the biological tissues (i.e. normal, and cancer liver cells). The structure of the biochip consists of actuator and sensor parts to manipulate, track, and characterize the biological tissues. The DEP electro-kinetic is preferred to manipulate the polarizable particles. While the manipulated particles are tracked using two different techniques, which are the capacitive sensor and the DeFET sensor.
In order to increase the variety of the tested particles, a low-cost technique using only joule heating-based microelectrode is proposed to identify the DNA of viruses (the hepatitis C virus (HCV)). The viruses can be detected using the aggregation of gold nanoparticles. However, the AuNPs aggregation is stated using an impedance spectroscopy technique. Impedance spectroscopy measures the resistance and capacitance properties of material via the application of a sinusoidal AC excitation signal. The impedance spectrum is obtained by changing the frequency over a wide range of AC.
In order to save time, the efforts, and the cost, all configurations are simulated before the fabricating to achieve the best design for each configuration. All configurations are simulated using two methods, which are the finite element method (FEM) using COMSOL Multiphysics 5.5, and the circuit simulation using cadence software.
The final design of the biochip is implemented using SKILL scripting of a cadence in order to build it accurately and in a little time. Then the fabricated biochips are tested using the biological tissues (i.e. normal and cancer liver cells) and the DNA of HCV. The simulation and experimental results confirm the efficiency and the accuracy of the proposed biochip in performing the tasks required of it.
Keywords: Lab on a chip – CMOS – Electro-kinetic – Dielectrophoresis - Cell tracking – DeFET – Capacitive sensor – Impedance spectroscopy – Joule Heating – Normal and Cancer liver cells – DNA – hepatitis C viruses.