title: Magnetically Alignable Bicelles with Unprecedented Stability Using Tunable Surfactants Derived from Cholic Acid.
abstract: Five novel surfactants were prepared by modifying the three hydroxy groups of sodium cholate with triethylene glycol chains endcapped with an amide (SC-C1, SC-nC4, and SC-nC5) or a carbamoyl group (SC-OnC4and SC-OtC4). The phase behavior of aqueous mixtures of these surfactants with 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC) was systematically studied by31P NMR spectroscopy. The surfactants endcapped with carbamate groups (SC-OnC4and SC-OtC4) formed magnetically alignable bicelles over unprecedentedly wide ranges of conditions, in terms of temperature (from 21-23 to >90 °C), lipid/surfactant ratio (from 5 to 8), total lipid content (5-20 wt %), and lipid type [DMPC, 1,2-dilauroyl-sn-glycero-3-phosphatidylcholine (DLPC), or 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC)]. In conjunction with appropriate phospholipids, the carbamate-endcapped surfactants afforded unique bicelles, characterized by exceptional thermal stabilities (from 0 to >90 °C), biomimetic lipid compositions (DMPC/POPC=25:75 to 50:50), and extremely large2H quadrupole splittings (up to 71 Hz).
authors.affiliation: Department of Chemistry and Biotechnology, School of Engineering, the, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Matsui
authors.affiliation: Department of Chemistry and Biotechnology, School of Engineering, the, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Uchida
authors.affiliation: RIKEN Center for Emergent Matter Science, Hirosawa 2-1, Wako, Saitama, 351-0198, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Ohtani
authors.affiliation: RIKEN Center for Emergent Matter Science, Hirosawa 2-1, Wako, Saitama, 351-0198, Japan.
authors.forename: Kuniyo
authors.initials: K
authors.lastname: Yamada
authors.affiliation: Graduate School of Engineering, Yokohama National University, Tokiwadai 79-5, Hodogaya-ku, Yokohama, 240-8501, Japan.
authors.forename: Arisu
authors.initials: A
authors.lastname: Shigeta
authors.affiliation: Graduate School of Engineering, Yokohama National University, Tokiwadai 79-5, Hodogaya-ku, Yokohama, 240-8501, Japan.
authors.forename: Izuru
authors.initials: I
authors.lastname: Kawamura
authors.affiliation: RIKEN Center for Emergent Matter Science, Hirosawa 2-1, Wako, Saitama, 351-0198, Japan.|Department of Chemistry and Biotechnology, School of Engineering, the, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Takuzo
authors.initials: T
authors.lastname: Aida
authors.affiliation: RIKEN Center for Emergent Matter Science, Hirosawa 2-1, Wako, Saitama, 351-0198, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ishida
mesh_terms: D019826:Cholic Acid / Q000737:chemistry*; D060526:Magnetic Fields; D008823:Micelles; D015394:Molecular Structure; D013501:Surface-Active Agents / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D008823:Micelles; D013501:Surface-Active Agents; D019826:Cholic Acid
keywords: bicelles; cholic acid; magnetic alignment; phospholipids; surfactants