Chee Guan Koh1, Xihai Kang2, Yubing Xie2, Bo Yu1, and L. James Lee3. (1) Department of Chemical and Biomolecular Engineering, The Ohio State University, 140 West 19th Avenue, Columbus, OH 43210, (2) NSEC Center for Affordable Nanoengineering of Polymer Biomedical Devices, The Ohio State University, 1381 Kinnear Road, Suite 100, Columbus, OH 43212, (3) Chemical and Biomolecular Engineering, The Ohio State University, 125A Koffolt, 140 West 19th, Columbus, OH 43210
We have demonstrated efficient delivery of plasmid encoding green fluorescent protein reporter (pGFP) into murine embryonic stem cells. The plasmid was condensed into nanocomplexes by conventional bulk mixing and by hydrodynamic focusing in a microfluidic device. By altering the ratio of the flow rates of pGFP and cationic polymer, e.g. polyethylenimine (PEI), small and uniformed nanoparticles were produced. The biophysical properties of these nanoparticles were characterized by dynamic light scattering (DLS), atomic force microscopy (AFM), and zeta potential measurement. We also used double labeled DNA/YOYO-1 and PEI/Rhodamine to visualize the cellular uptake and trafficking of these particles into the cells by confocal microscopy. The transfection efficiency and cell viablility were determined.