Capture and analysis of double-stranded DNA with the α-hemolysin nanopore: Fundamentals and applications

The α-hemolysin nanopore has attracted much attention as a tool for the single-molecule analysis of DNA due to its potential as an ultra-sensitive, specific, and label-free sensing technique. The vast majority of DNA sensing research with the α-hemolysin nanopore has focused on interrogating single-stranded DNA. Nevertheless, the structure of the α-hemolysin pore, specifically the circa 32.6 cubic nanometer vestibule, is of sufficient size for a short section of double-stranded DNA (dsDNA) to reside before unzipping into its single-stranded constituents. In this review, we describe past and current literature relating to the rich information that can be obtained from the interrogation of dsDNA while residing within the α-hemolysin nanopore vestibule, and the subsequent voltage-driven unzipping of the residing DNA into its single-stranded constituents. Applications for dsDNA interrogation and unzipping that have been implemented include DNA sequencing, disease diagnosis, and the identification of epigenetic modifications.