Fabrication of Two-Layered Channel System with Embedded Electrodes to Measure Resistance Across Epithelial and Endothelial Barriers

摘要

This manuscript describes a straightforward fabricationnprocess for embedding Ag/AgCl electrodes within a twolayernpoly(dimethylsiloxane) (PDMS) microfluidic chipnwhere an upper and a lower channel are separated by ansemiporous membrane. This system allows for the reliablenreal-time measurement of transendothelial and transepithelialnelectrical resistance (TEER), an accepted quantificationnof cell monolayer integrity, across cells culturednon membranes inside the microchannels using impedancenspectroscopy. The technique eliminates the need forncostly or specialized microelectrode fabrication, enablingncommercially available wire electrodes to easily be incorporatedninto PDMS microsystems for measuring TEERnunder microfluidic environments. The capability of measuringnimpedance across a confluent cell monolayer isnconfirmedusing(i)brain-derivedendothelialcells(bEND.3),n(ii) Madin Darby Canine Kidney Cells (MDCK-2), andnmouse myoblast (C2C12) (all from ATCC, Manassas, VA).nTEER values as a function of cell type and cell culture timenwere measured and both agree with previously publishednvalues from macroscale culture techniques. This systemnopens new opportunities for conveniently resolving bothntransendothelial and transepithelial electrical resistancento monitor cell function in real-time in microfluidic cellncultures.