title: Water and proton conduction through carbon nanotubes as models for biological channels.
abstract: Carbon nanotubes, unmodified (pristine) and modified through charged atoms, were simulated in water, and their water conduction rates determined. The conducted water inside the nanotubes was found to exhibit a strong ordering of its dipole moments. In pristine nanotubes the water dipoles adopt a single orientation along the tube axis with a low flipping rate between the two possible alignments. Modification can induce in nanotubes a bipolar ordering as previously observed in biological water channels. Network thermodynamics was applied to investigate proton conduction through the nanotubes.
authors.affiliation: Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
authors.forename: Fangqiang
authors.initials: F
authors.lastname: Zhu
authors.forename: Klaus
authors.initials: K
authors.lastname: Schulten
mesh_terms: D040761:Biomimetic Materials / Q000737:chemistry*; D032701:Biomimetics / Q000379:methods*; D003198:Computer Simulation; D004058:Diffusion; D004553:Electric Conductivity; D017097:Electric Impedance; D007473:Ion Channels / Q000737:chemistry*; D046911:Macromolecular Substances; D008567:Membranes, Artificial; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011522:Protons; D055672:Static Electricity; D014867:Water / Q000737:chemistry*
chemical_list: D007473:Ion Channels; D046911:Macromolecular Substances; D008567:Membranes, Artificial; D037742:Nanotubes, Carbon; D011522:Protons; D014867:Water