title: Novel biomimetic systems based on amphiphilic compounds with a diterpenoid fragment: role of counterions in self-assembly.
abstract: Novel biomimetic systems are designed based on cationic surfactants composed of an isosteviol moiety and different counterions, namely bromide (S1) and tosylate (S2). The counterion structure is shown to play a crucial role in the surfactant association. A number of methods used provide evidence that only one type of aggregate, i.e., micelles are observed in the S2 systems, while a concentration-dependent association occurs in the case of S1. The DLS and fluorescence anisotropy measurements reveal that the micelle-vesicle-micelle transitions probably occur with the S1 system. The occurrence of small aggregates near the critical micelle concentration with radii of 2.5 nm is supported by NMR self-diffusion data. The Orange OT solubilization results strongly support the idea of a second threshold in the S1 system around 0.025 mM and provide evidence that hydrophobic domains occur in the aggregates. The latter property and the capacity to integrate with the lipid bilayer make it possible to suggest the newly synthesized surfactants as effective nanocontainers for hydrophobic guests.
authors.affiliation: A.E. Arbuzov Institute of Organic and Physical Chemistry of Kazan Scientific Center of Russian Academy of Sciences, 8, ul. Arbuzov, Kazan 420088, Russia.
authors.forename: Mikhail A
authors.initials: MA
authors.lastname: Voronin
authors.forename: Dinar R
authors.initials: DR
authors.lastname: Gabdrakhmanov
authors.forename: Ravil N
authors.initials: RN
authors.lastname: Khaibullin
authors.forename: Irina Yu
authors.initials: IY
authors.lastname: Strobykina
authors.forename: Vladimir E
authors.initials: VE
authors.lastname: Kataev
authors.forename: Bulat Z
authors.initials: BZ
authors.lastname: Idiyatullin
authors.forename: Dzhigangir A
authors.initials: DA
authors.lastname: Faizullin
authors.forename: Yuriy F
authors.initials: YF
authors.lastname: Zuev
authors.forename: Lucia Ya
authors.initials: LY
authors.lastname: Zakharova
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Konovalov
mesh_terms: D016880:Anisotropy; D032701:Biomimetics; D004058:Diffusion; D057927:Hydrophobic and Hydrophilic Interactions; D007477:Ions; D008027:Light; D008051:Lipid Bilayers; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D012542:Scattering, Radiation; D013050:Spectrometry, Fluorescence; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D013729:Terpenes / Q000737:chemistry*
chemical_list: D007477:Ions; D008051:Lipid Bilayers; D008823:Micelles; D013501:Surface-Active Agents; D013729:Terpenes