system-level biochip for impedance sensing and programmable manipulation of bladder cancer cells系统级生物芯片的阻抗传感和膀胱癌细胞的可编程操作.pdf

Sensors 2011, 11, 11021-11035; doi:10.3390/s111111021 OPEN ACCESS sensors ISSN 1424-8220 /journal/sensors Article System-Level Biochip for Impedance Sensing and Programmable Manipulation of Bladder Cancer Cells Cheng-Hsin Chuang *, Yao-Wei Huang and Yao-Tung Wu Department of Mechanical Engineering, Southern Taiwan University, Tainan 71005, Taiwan; E-Mails: z5972324@ (Y.-W.H.); su.tw (Y.-T.W.) * Author to whom correspondence should be addressed; E-Mail: chchuang@.tw; Tel: +886-6-301-0081; Fax: +886-6-242-5092. Received: 8 October 2011; in revised form: 17 November 2011 / Accepted: 17 November 2011 / Published: 23 November 2011 Abstract: This paper develops a dielectrophoretic (DEP) chip with multi-layer electrodes and a micro-cavity array for programmable manipulations of cells and impedance measurement. The DEP chip consists of an ITO top electrode, flow chamber, middle electrode on an SU-8 surface, micro-cavity arrays of SU-8 and distributed electrodes at the bottom of the micro-cavity. Impedance sensing of single cells could be performed as follows: firstly, cells were trapped in a micro-cavity array by negative DEP force provided by top and middle electrodes; then, the impedance measurement for discrimination of different stage of bladder cancer cells was accomplished by the middle and bottom electrodes. After impedance sensing, the individual releasing of trapped cells was achieved by negative DEP fo