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Delivery of molecules into cells using localized single cell electroporation on ITO micro-electrode based transparent chip

Institute of Nano Engineering and Microsystems, National Tsing Hua University, Hsinchu City, Taiwan.
Biomedical Microdevices (Impact Factor: 2.77). 06/2012; 14(5):811-7. DOI: 10.1007/s10544-012-9660-9
Source: PubMed

ABSTRACT Single cell electroporation is one of the nonviral method which successfully allows transfection of exogenous macromolecules into individual living cell. We present localized cell membrane electroporation at single-cell level by using indium tin oxide (ITO) based transparent micro-electrodes chip with inverted microscope. A focused ion beam (FIB) technique has been successfully deployed to fabricate transparent ITO micro-electrodes with submicron gaps, which can generate more intense electric field to produce very localized cell membrane electroporation. In our approach, we have successfully achieved 0.93 μm or smaller electroporation region on the cell surface to inject PI (Propidium Iodide) dye into the cell with 60 % cell viability. This experiments successfully demonstrate the cell self-recover process from the injected PI dye intensity variation. Our localized cell membrane electroporation technique (LSCMEP) not only generates reversible electroporation process but also it provides a clear optical path for potentially monitoring/tracking of drugs to deliver in single cell level.

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Available from: Tuhin Subhra Santra, May 25, 2015
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