Hsiang-Yu Wang, Chemical Engineering, Purdue University, West Lafayette, IN 47906, Nashley Mascarenhas, Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907-2088, Shaunak A. Kothari, Biomedical Engineering, Purdue University, 500 Central Drive, West Lafayette, IN 47907-2022, and Chang Lu, Agriculture and Biological Engineering, Chemical Engineering, Purdue University, West Lafayette, IN 47906.
Electroporation is an effective way to deliver molecules such as drugs or DNA into mammalian cells. Generally, a specialized pulse generator is required to conduct the electroporation. In this study, we demonstrated the electroporation of CHO cells on a microfluidic device using A DC power supply. The device contained a channel with different sections. The electroporation happened in the narrow sections (width = 50 micrometers) and the wide sections had a width of 500 micrometers. According to Ohm's law, the field strength inside the electroporation sections was amplified to 10 times of that inside the wide sections. The cells experienced pulse-like electric field while traveling through the channel. Due to the merit of the amplification, the pulse-like electric field could be achieved using merely a DC power supply. We designed the channels equivalent to single or multiple pulses to study the effects of number of pulses on the electroporation. The influences of other parameters to the electroporation were also investigated. These parameters included the field strength inside the electroporation section and the time of exposure of cells to the electroporation field strength. The delivery of small molecules into the CHO cell was confirmed by the uptake of SYTOX Green. The same dye was used to determine the viability of electroporated cells. We also demonstrated the transfection of CHO cells using the pEGFP-C1 plasmid. Our device will provide a simple and efficient means to transfer DNA or other molecules into mammalian cells.