10:30 AM - 10:45 AM
△
[7a-A503-7] Solid-state Nanopore DNA Sequencing:
Single-nucleotide Discrimination and Bidirectional DNA Translocation
Keywords:nanopore, DNA sequencer, DNA
Nanopore DNA sequencing attracts researchers due to its potential for long-reads, fast analysis and high throughput. The precise semiconductor process can fabricate a solid-state nanopore with high quality at low costs. Solid-state nanopore-based sequencing based on detection of ionic current blockage, however, has been still under development toward reading DNA at single-nucleotide sensitivity. Our state-of-the-art technology enables to fabricate a precisely-controlled ultrathin SiN nanopore with wafer scale [1]. Nanopores, having diameters of a few nanometers and thickness of a several nanometers at sub-nanometer accuracy, can be produced electrically by simple in-situ process. We have recently developed a single-molecular DNA sensing system with the nanopore unit and a bidirectional DNA-motion control unit, achieving single-nucleotide sensitivity and reversible DNA translocation.
Here we present a proof-of-concept data demonstrating single nucleotide discrimination in a tandem repeat DNA with long (> 50 kb) size. We observe the sequence-dependent blockage current levels, corresponding to the di-,tri- and tetra nucleotide repeats. This result clearly indicates that our ultrathin SiN nanopore can read ssDNA with single nucleotide sensitivity. We estimate the nucleotide-resolution of the nanopore as 4-mer, contributing to a fine read accuracy. The bidirectional DNA translocation is driven by the piezo actuator with nanometer-scale accuracy. The ionic blockade signature follows the translocation speed of the piezo actuator at up to averaged speed of 100 base per second. The bidirectional DNA measurement would enable a highly-trusted sequence to be obtained from multiple passes on a same single molecule.
These proof-of-concept and encouraging data opens the door to solid-state nanopore DNA sequencer. Detailed data and advantages of our developed system are discussed.
[1] I. Yanagi, et al. Fabrication of 3-nm-thick Si3N4 membranes for solid-state nanopores using the poly-Si sacrificial layer process. Sci. Rep. 5, 14656 (2015).
Here we present a proof-of-concept data demonstrating single nucleotide discrimination in a tandem repeat DNA with long (> 50 kb) size. We observe the sequence-dependent blockage current levels, corresponding to the di-,tri- and tetra nucleotide repeats. This result clearly indicates that our ultrathin SiN nanopore can read ssDNA with single nucleotide sensitivity. We estimate the nucleotide-resolution of the nanopore as 4-mer, contributing to a fine read accuracy. The bidirectional DNA translocation is driven by the piezo actuator with nanometer-scale accuracy. The ionic blockade signature follows the translocation speed of the piezo actuator at up to averaged speed of 100 base per second. The bidirectional DNA measurement would enable a highly-trusted sequence to be obtained from multiple passes on a same single molecule.
These proof-of-concept and encouraging data opens the door to solid-state nanopore DNA sequencer. Detailed data and advantages of our developed system are discussed.
[1] I. Yanagi, et al. Fabrication of 3-nm-thick Si3N4 membranes for solid-state nanopores using the poly-Si sacrificial layer process. Sci. Rep. 5, 14656 (2015).