Date of Graduation


Document Type


Degree Type



Statler College of Engineering and Mineral Resources


Lane Department of Computer Science and Electrical Engineering

Committee Chair

Yuxin Liu


Carbon nanomaterials, including carbon nanotubes (CNTs) gain increasing interest in commercial and biomedical applications. Adverse health effects of engineered CNTs may result from either direct exposure during production, inadvertent exposure during use of by-products, and/or release of these materials into the environment. Recent studies have shown that CNTs can induce cytotoxicity, apoptosis, DNA damage, and tumor formation in animals, suggesting their potential toxicity in humans. To address the current needs in developing in vitro cell assays for assessment of the adverse health effects of CNTs in lung respiratory, we have developed a microfluidic impedance-metric biosensor for investigation of multi-walled CNTs (MWCNTs) effects on the cultured monolayer of human lung epithelial cells. Microfluidic based cell assays provide the ability and flexibility to control spatiotemporal biochemical parameters, and further for manipulating cell behaviors in well-established microenvironments. The biosensor consists of a transparent porous polyester cell-culture membrane embedded with a double-layer poly(dimethylsiloxane) (PDMS) microfluidic channels. Two electrodes can be easily inserted to the biosensors for impedance measurements. Experimental results show that human lung epithelial cells can form a tight monolayer within 10 days culture inside the device. Raw, purified and functionalized MWCNTs are introduced to the monolayer and their effects on epithelial permeability are measured and reflected by impedance spectroscopy. The miniaturized impedance-metric biosensor can provide label-free evaluation of the impacts of CNTs on the epithelial monolayer integrity with accurate reading and reduced noises.