A hydrophilic polymer based microfluidic system with planar patch clamp electrode array for electrophysiological measurement from cells

• A hydrophilic polymer based microfluidic system with planar patch clamp electrode array for whole cell current recording.
• Flexible fabrication using UV-assisted molding method.
• A relatively high gigaseal success rate of 44% with no need for surface modification compared with PDMS based chip.
• High capillary flow rates with two orders of magnitude greater than those for PDMS channels with the same channel dimension.
• Rapid intracellular and extracellular solution exchange with high stability of gigaseals.

This paper presents a microfluidic planar patch clamp system based on a hydrophilic polymer poly(ethylene glycol) diacrylate (PEGDA) for whole cell current recording. The whole chip is fabricated by UV-assisted molding method for both microfluidic channel structure and planar electrode partition. This hydrophilic patch clamp chip has demonstrated a relatively high gigaseal success rate of 44% without surface modification compared with PDMS based patch clamp devices. This chip also shows a capability of rapid intracellular and extracellular solution exchange with high stability of gigaseals. The capillary flow kinetic experiments demonstrate that the flow rates of PEGDA microfluidic channels are around two orders of magnitude greater than those for PDMS-glass channels with the same channel dimensions. This hydrophilic polymer based patch clamp chips have significant advantages over current PDMS elastomer based systems such as no need for surface modification, much higher success rate of cell gigaseals and rapid solution exchange with stable cell gigaseals. Our results indicate the potential of these devices to serve as useful tools for pharmaceutical screening and biosensing tasks.