Single-cell Trapping Utilizing Negative Dielectrophoretic Quadrupole and Microwell Electrodes

• Main Authors: Pao-Hua Huang, 黃寶樺
• Other Authors: Ling-Sheng Jang
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/82862922693875438016

碩士 === 國立成功大學 === 電機工程學系碩博士班 === 97 === The handling of individual cells, which has attracted increasing attention, is a key technique in cell engineering such as gene introduction, drug injection, and cloning technology. MEMS (Micro-Electro-Mechanical Systems) technology is established and is more efficient rather than the conventional ones. DEP (dielectrophoresis) is one of the electrical methods to manipulate μ-particles, and can be easily combined with subsequent analyses based on electric fields. Besides, negative DEP is practicable in trapping living cells suspended in physiological media. In this research, two kinds of microelectrodes are combined to achieve single particle manipulation and trapping. One is the outer quadrupole geometry, which aggregates particles to the center region for being captured. The other one is the inner negative dielectrophoresis (nDEP) microwell (at the center of the quadrupole), which primarily traps the particles nearby. The collecting ability of such geometry is adopted to increase the trapped possibility of the nDEP microwell, and therefore launching an excess of particles is needless. In this way, we can sufficiently use the bio-particles in the droplet under the condition of limited sample source. Single-size latex beads and single cells are successfully held and proved here. Additionally, circulating flows are observed during the experiments, and we found that convective flows can be utilized well to make more accurate manipulation on particles in two dimensions. The drag force caused by fluid flows exerted on particles is also compared with the nDEP force. We demonstrate this trapping mechanism in capture and manipulation on single particles, and the experiment results are in good agreement with the numerical simulation solutions.