Bolaform surfactants with polyoxometalate head groups and their assembly into ultra-small monolayer membrane vesicles

نویسندگان

  • Steve Landsmann
  • Martin Luka
  • Sebastian Polarz
چکیده

Surfactants are indispensable in established technologies as detergents or emulsification agents, and also in recent studies for controlling the growth of nanoparticles or for creating nanocarriers. Although the properties of conventional, organic surfactants are thoroughly explored, strong interest persists in surfactants that possess unique features inaccessible for ordinary systems. Here we present dipolar, bolaform surfactants with a head group comprising of 11 tungsten atoms. These novel compounds are characterized by an exceptionally low critical self-organization concentration, which leads to monolayer vesicles with a diameter of only 15 nm, that is, substantially smaller than for any other system. The membrane of the vesicles is impermeable for water-soluble and oil-soluble guests. Control over release kinetics, which can be followed via the quantitative fluorescence quenching of confined fluorophores, is gained by means of pH adjustments.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Passing Current through Electrically Conducting Lyotropic Liquid Crystals and Micelles Assembled from Hybrid Surfactants with π-Conjugated Tail and Polyoxometalate Head

The solvent-mediated ability for molecularly encoded self-assembly into states of higher order (micelles, lyotropic liquid crystals) embodies the basis for many applications of surfactants in science and society. Surfactants are used frequently in recipes for nanoparticle synthesis. Because ordinary surfactants comprise insulating constituents (alkyl groups as side-chains and charged organic he...

متن کامل

Polyoxometalate-Engineered Building Blocks with Gold Cores for the Self-Assembly of Responsive Water-Soluble Nanostructures.

The controlled assembly of gold nanoparticles (AuNPs) with the size of quantum dots into predictable structures is extremely challenging as it requires the quantitatively and topologically precise placement of anisotropic domains on their small, approximately spherical surfaces. We herein address this problem by using polyoxometalate leaving groups to transform 2 nm diameter gold cores into rea...

متن کامل

Chapter 3 Immiscible Langmuir monolayers: Interactions between the polar head groups of cholesterol and octylcyanobiphenyl

Mixed Langmuir monolayers are ideal systems to mimic biological membranes [1, 2]. Studies on mixed monolayers provide information about the interactions involved, miscibility and stability of the monolayer. It is known that cholesterol(Ch) is found in bilayer membranes and lipoproteins. Ch regulates the transport and barrier properties of the membranes [3]. Lung surfactant in the human body is ...

متن کامل

Reverse-vesicle formation of organic-inorganic polyoxometalate-containing hybrid surfactants with tunable sizes.

The formation of reverse-vesicular structures of the polyoxometalate-containing hybrid surfactants [nBu(4)N](3)[MnMo(6)O(18){(OCH(2))(3)-CNHCO(CH(2))(n-2)CH(3)}(2)] (Mn-Anderson-C(n), n=6, 16) in nonpolar medium was achieved by titrating toluene into Mn-Anderson-C(n)/acetonitrile (MeCN) solution. Stepwise change of the solvent polarity induces self-association of the hydrophilic Mn-Anderson clu...

متن کامل

Theory of spontaneous vesicle formation in surfactant mixtures.

The curvature elastic energy of bilayer vesicles formed by a mixture of two surfactants, which individually form either micelles or lamellar bilayer phases is described theoretically. In the limit of large bending elastic modulus K being much greater than the temperature T, the free energy is minimized by vesicles with different concentrations of the two surfactants in each monolayer of the bil...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره 3  شماره 

صفحات  -

تاریخ انتشار 2012