CHM2046 - Lecture Nanotube Membranes

CHM2046 - Lecture Nanotube Membranes - DNA...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: DNA Biofunctionalized Nanotube Membranes* Charles R. Martin Department of Chemistry Department of Anesthesiology and Center for Research at the Bio/Nano Interface University of Florida *Some interesting new things DNA molecules can do. Outline A brief introduction to biological ion channels. C enter for Research at the B io/N ano Interface C enter for Research at the B io/N ano Interface Highly selective chemical transport across cell membranes. DNA biofunctionalized Au nanotubes are voltage-gated ion channel mimics. Template-synthesized nanotubes as ion channels mimics. Voltage-gating of transmembrane ion currents. Selective DNA transport through DNA biofunctionalized gold nanotube membranes . Protein Channels – Nature’s Quintessential Bio/Nano Devices Cell Membrane - Impermeable lipid bilayer Membrane-Bound Protein Channel Key Functions of Protein Channels: Transport specific molecules and ions across the cell membrane. Electrical signaling (e.g., voltage-gating ) in nerve and muscle cells. Selective Transport – The Channel is a Nanotube with a Binding Site that Selects the Molecule/Ion to be Transported Abramson, et al. Science 2003 , 301 , 610. Model of Lactose Permease from E. Coli Bilayer Membrane Hydrophilic cavity containing sugar binding site Bound sugar C enter fo r R esearch at th e B io /N an o In terface C enter fo r R esearch at th e B io /N an o In terface Electrical Signaling – Ion Channels Open and Close in Response to Specific Chemical or Electrical Signals Lipid bilayer membrane Out In Outer helix P o r e h e l i x Model of a Voltage-Gated Potassium Channel From B. Hille, “Ion Channels of Excitable Membranes,” Vol 3. Current-Voltage Curve for a Voltage-Gated Potassium Channel Transmembrane Potential (mV) Transmembrane Current (pA) Open or “On” State Y. Jiang, A. Lee, J. Chen, M. Cadene, B.T. Chait, R. MacKinnon, Nature 417 (2002) 515. Closed or “Off” State Artificial Channels – Why would we want to Mimic The Selective-Transport and Open/Close-Gating Functions of Nature’s Channels? Selective-Transport – Synthetic membranes containing chemically selective artificial channels could be used to do bioseparations – e.g. pharmaceutical, genomic, proteomic. Open/Close – This gating function can be used as a signal transduction scheme in biosensor platforms. But how does one make an artificial channel ? Template synthesis provides a route for preparing nanotubes of any desired dimensions , any desired shape and composed of any desired material , to yield nanotubes having any desired properties . Template-Synthesized Nanotubes June 11, 2001 cover of Chemical and Engineering News . Bilayer Membrane Hydrophilic cavity containing sugar binding site Bound sugar Mimicking the Selective Transport Function Like natures channels, we incorporate biochemical molecular-recognition agents into our nanotubes so that they selectively recognize, bind and transport specific molecules Schematic of a Nanotube Membrane with a...
View Full Document

{[ snackBarMessage ]}

Page1 / 44

CHM2046 - Lecture Nanotube Membranes - DNA...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online