Fabrication and characterization of solid-state nanopore arrays for high-throughput DNA sequencing

摘要

We report the fabrication and characterization of uniformly sized nanopore arrays, integrated into an optical detection system for high-throughput DNA sequencing applications. Nanopore arrays were fabricated using focused ion beam milling, followed byTiO _2 coating using atomic layer deposition. TheTiO _2 layer decreases the initial pore diameter down to the sub-10nm range, compatible with the requirements for nanopore-based sequencing using optical readout. We find that theTiO _2 layers produce a lower photoluminescence background as compared with the more widely used Al _2O _3 coatings. The functionality of the nanopore array was demonstrated by the simultaneous optical detection of DNA-quantum dot conjugates, which were electro-kinetically driven through the nanopores. Our optical scheme employs total internal reflection fluorescence microscopy to illuminate a wide area of theTiO _2-coated membrane. A highly parallel system for observing DNA capture events in a uniformly sized 6×6 nanopore array was experimentally realized.