Nanopore arrays for cell monitoring
Electrolytic contacts to living cells in a physiological environment are an important tool for the investigation and monitoring of trans-membrane ion channel activity. A prominent example is the recording of action potentials of neurons. This requires a stable local contact to the cell membrane with a sufficiently high resistance relative to the surrounding electrolyte ("gigaseal"). In addition, damage of the cell membrane or interference with the natural function of trans-membrane channels have to be avoided. The current state-of-the-art in this field is defined by the "patch-clamp" technique, where local contacts to cell membranes are established with a submicron quartz pipette. The aim of this project is to replace such pipettes by ordered nanopore arrays in a thin freestanding silicon membrane. This would open the possibility of combining the electrolytic cell contacts with integrated electronics or nano-electromechanical functionality. Towards this goal, we have developed a method to prepare regular nanopore arrays with periods of 1-2 µm and pore diameters down to 100 nm. We have also shown that such arrays form gigaseal contacts with artificial membranes. Future work will focus on the integration of such pore arrays with microfluidics and on-chip data processing. This work was supported by Bayerische Forschungsstiftung (FORNANO).
