Enhanced detection of single molecule and stochastic interactions under nanoconfinement

Individual molecular behavior influences biochemical processes and the properties of individual cells, ultimately involving the complex behavior of living beings. Many techniques have emerged to understand the single molecule. The single-molecule detection technique, namely the nanopore sensing method is being developed as a powerful tool to probe detailed investigation of single molecules because of its applications to diverse fields of nanoscience like drug discovery, early detection of diseases, and medical diagnostics. Nanopipette, as a sub-type of solid-state nanopores, has long been used to detect and identify proteins and DNAs for several years. However, an effective method for the detection of molecules with 1-2 nm size was currently lacking through nanopipette due to nanopipette size variation and fast translocation speed of biomolecules. In this talk, I will show our new method to employ the nanoconfinement effect of the nanopipette tip to detect small molecules, including nucleotides and short peptides, with high event rates and high signal-to-noise ratio. We have also successfully probed the intermolecular interactions between small biomolecules.