Kim, Young-Ji2010-02-192010-02-192009-10https://hdl.handle.net/11299/58234University of Minnesota Ph.D. dissertation. October 2009. Major: Electrical Engineering. Advisor: Euisik Yoon, Ph.D. 1 computer file (PDF); vii, 95 pages, appendices A-B.This thesis presents a novel, multi-purpose microfluidic platform for single-cell and pairwise cell interaction assay. In particular, this thesis demonstrates an efficient scheme for (1) controllable cell loading at single-cell resolution in each microchamber, (2) a microchamber isolation scheme for creation of highly parallel isolated microenvironments around small groups of cells in close proximity and (3) biological assays to examine not only single-cell culture assays, but also the effect of cell-cell interactions, with secreted soluble factors between isolated pairs of cells, which is very difficult to measure in other platforms due to fast dilution into a large volume of media. This goal was accomplished by fabricating an array of microchambers for cell loading at single-cell resolution by using standard photolithography and PDMS (Polydimethylsiloxane) soft lithography techniques. Each microchamber is basically composed of a capture site for single-cell trapping, a cell culture (reaction) chamber, an actuation membrane and control valves, located above the microchamber, for single cell loading and microchamber isolation by applying pneumatic pressure. To examine the capability of the developed microchamber array as a multipurpose cell-assay platform, this thesis presents two different single-cell assays. First, single cell culture analysis was demonstrated using muscle stem cells and prostate cancer cells. In this experiment, proliferation, differentiation and apoptosis of muscle stem cells as well as three different sub-clones of prostate cancer cell line (PC3) by clonal culture are observed. Second, pairwise cell interaction analysis was demonstrated with co-culture between C2C12 (myoblast)-PC3 and C2C12-HUVEC (endothelial cells). The results demonstrated that soluble factors, including growth factors secreted from both PC3 and HUVEC, enhanced the proliferation of C2C12 under controlled microchamber isolation.en-USCell interaction assayCell loadingMicrochambersMicrofluidic platformsElectrical EngineeringThesis or Dissertation