Dissertation Defense-Markus Gnerlich

Date:
Friday, August 26, 2011 at 1:00PM
in Lewis Lab room 316

Title:
Microelectromechanical Actuator and Sensor System for Measuring the Mechanical Compliance of Biological Cells

Abstract:
An integrated biological microelectricalmechanical system (BioMEMS) has been developed for in vitro cell biomechanics experiments. This system combines a lateral force sensor, an electrostatic actuator array, an on-chip heater, resistance temperature detector and cell positioning dielectrophoresis electrodes in a fully submersible and reusable 4 mm by 4 mm chip. All mechanical structures, including the piezoresistive elements in the force sensor, are defined by a single mask on a silicon-on-insulator (SOI) wafer without the need for a doping or annealing step, and are easily integrated with other SOI MEMS. The optimal design of this force sensor is examined, as well as the sensitivity characterization results from fabricated devices. The operation of the electrostatic actuator array is also examined in the liquid environment. Finally, a calibrated force sensor is used to measure the reaction forces of suspended fibroblast cells (NIH3T3) and osteoblast cells (MC3T3) during compression, and the data is fit to a combined viscoelastic-contact model.

Committee:
Prof. Svetlana Tatic-Lucic (Chair)
Prof. Peter Butler
Prof. Xuanhong Cheng
Prof. Susan Perry
Prof. Arkady Voloshin
Prof. Marvin White