Electrokinetic Transport in Heterogeneous Micro and Nano-channels

Electrokinetic transport in micro and nano-channels was investigated. Classical electric double layer (EDL) theory was extended to describe heterogeneous interface in micro and nano-channels. It is found that nano-pattern can affect the local EDL distribution where micro- or macro-pattern effect on each other can be safely neglected. Based on the extended EDL theory, a correlation between electrokinetic parameters and heterogeneity was derived.;A numerical model was developed to study the flow behaviour in interstitium by considering electrokinetic effects. Numerical simulation shows that the flow rate produced by electroosmotic flow is on the' same order of that caused by pressure driven flow. By incorporating the electrokinetic effects in interstitial flow, the extremely low hydraulic conductivity of interstitium can be easily explained. A mathematical model to simulate stem cell differentiation and cell transport process in bone marrow is presented in this thesis. The proposed model was written in a general form and may be used to simulate a generic cell differentiation pathway in vivo or in vitro. Literature experimental data concerning the spatial distribution of stem cells are successfully compared with model results.;Experimentally, zeta potential value determined by streaming potential method on rough surfaces was performed to illustrate heterogeneous surface effect. Experimental results confirmed that the proposed theory can be employed to evaluate electrokinetic parameters of heterogeneous surfaces. Surface modification of polymers which can be utilized to create heterogeneous pattern was described. A method to measure electrokinetic parameters of porous media was also investigated.