title: Handedness enantioselection of carbon nanotubes using helical assemblies of flavin mononucleotide.
abstract: In order to truly unlock advanced applications of single-walled carbon nanotubes (SWNTs), one needs to separate them according to both chirality and handedness. Here we show that the chiral D-ribityl phosphate chain of flavin mononucleotide (FMN) induces a right-handed helix that enriches the left-handed SWNTs for all suspended (n,m) species. Such enantioselectivity stems from the sp(3) hybridization of the N atom anchoring the sugar moiety to the flavin ring. This produces two FMN conformations (syn and anti) analogous to DNA. Electrostatic interactions between the neighboring uracil moiety and the 2'-OH group of the side chain provide greater stability to the anti-FMN conformation that leads to a right-handed FMN helix. The right-handed twist that the FMN helix imposes to the underlying nanotube, similar to "Indian burn", causes diameter dilation of only the left-handed SWNTs, whose improved intermolecular interactions with the overlaying FMN helix, impart enantioselection.
authors.affiliation: Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3136, USA.
authors.forename: Sang-Yong
authors.initials: SY
authors.lastname: Ju
authors.forename: Darlington C
authors.initials: DC
authors.lastname: Abanulo
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Badalucco
authors.forename: José A
authors.initials: JA
authors.lastname: Gascón
authors.forename: Fotios
authors.initials: F
authors.lastname: Papadimitrakopoulos
mesh_terms: D002942:Circular Dichroism; D005486:Flavin Mononucleotide / Q000737:chemistry*; D006860:Hydrogen Bonding; D008954:Models, Biological; D037742:Nanotubes, Carbon / Q000737:chemistry*; D017433:Protein Structure, Secondary; D013237:Stereoisomerism
chemical_list: D037742:Nanotubes, Carbon; D005486:Flavin Mononucleotide