Wednesday, 4 October 2017: 15:00
Chesapeake L (Gaylord National Resort and Convention Center)
In this presentation, we discuss applications of scanning electrochemical microscopy (SECM) to high-resolution imaging of biological and artificial nanopores. SECM imaging enables us to obtain unprecedented information about the kinetics, pathways, and mechanism of molecular transport through single nanopores. We characterize nanopipet electrodes as nanoscale SECM probes by transmission electron microscopy to verify their small diameters of ~30 nm. The resultant high spatial resolution of our SECM instrument is quantitatively demonstrated by imaging ion transport through the single nanopores of a thin solid silicon membrane. The nanoscale SECM approach thus established is applied to image a biological nanopore, the nuclear pore complex (NPC), in aqueous solution, which eliminates artifacts that are caused when the NPC is imaged by electron microscopy in vacuum and atomic force microscopy in air. Our SECM study of single NPCs is significant, because it will led to a greater mechanistic understanding of molecular transport through the NPC, which plays crucial roles in the gene expression regulation and gene delivery and is linked to many human diseases and therapeutics of genetic disorders.