Single-stranded Dna Detection via Chemically Modified Alamthicin Nanopore at Single Molecule Level

This paper describes the electrical detection of single-stranded DNA (ssDNA) at the single molecule level using an engineered alamethicin (Alm) channel embedded in bilayer lipid membranes (BLMs). Nanopore sequencing has the potential to become a direct, fast and inexpensive DNA sequencing methodology (Fig. 1). We propose here the chemically covalent dimmers of Alm (di-Alm) in which monomers were linked at their N-terminal ends and the di-Alm forms mainly the 6-mers (1.3 nm dia.). In addition, the conductance states were stabilized with lifetimes up to 200-fold longer than the same sates observed with monomers. Using the di-Alm nanopore, we can observe the slow ssDNA translocation and this finding highlight the importance of the di-Alm in the future of nanopore sequencing.