References of "Advanced Functional Materials"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailFunctional nanogels as platforms for imparting antibacterial, antibiofilm, and antiadhesion activities to stainless steel
Faure, Emilie ULg; Falentin, Céline ULg; Svaldo Lanero, Tiziana ULg et al

in Advanced Functional Materials (2012), 22(24), 5271-5282

In this work, long-term antibacterial, antiadhesion, and antibiofilm activities are afforded to industrial stainless steel surfaces following a green and bio-inspired strategy. Starting from catechol ... [more ▼]

In this work, long-term antibacterial, antiadhesion, and antibiofilm activities are afforded to industrial stainless steel surfaces following a green and bio-inspired strategy. Starting from catechol bearing synthetic polymers, the film cross-linking and the grafting of active (bio)molecules are possible under environmentally friendly conditions (in aqueous media and at room temperature). A bio-inspired polyelectrolyte, a polycation-bearing catechol, is used as the film-anchoring polymer while a poly(methacrylamide)-bearing quinone groups serves as the cross-linking agent in combination with a polymer bearing primary amine groups. The amine/quinone reaction is exploited to prepare stable solutions of nanogels in water at room temperature that can be easily deposited to stainless steel. This coating provides quinonefunctionalized surfaces that are then used to covalently anchor active (bio) molecules (antibiofi lm enzyme and antiadhesion polymer) through thiol/ quinone reactions. [less ▲]

Detailed reference viewed: 117 (30 ULg)
Full Text
Peer Reviewed
See detailZnO/PVA Macroscopic Fibers Bearing Anisotropic Photonic Properties
Kinadjian, Natacha ULg; Achard, Marie-France; Julian-lopez, Beatriz et al

in Advanced Functional Materials (2012)

Composite PVA/ZnO-nanorods fibers, synthesized through co-axial flux extrusion exhibit higher anisotropic photonic properties, both in absorption and emission, as a result of the collective alignment of ... [more ▼]

Composite PVA/ZnO-nanorods fibers, synthesized through co-axial flux extrusion exhibit higher anisotropic photonic properties, both in absorption and emission, as a result of the collective alignment of the ZnO nanorods along the main axis of the PVA fiber. This photonic anisotropy is triggered by a synergistic interaction between the PVA matrix, stretched above the glass transition temperature (Tg), and cooled down under strain. Compared with non-elongated fibers that present an isotropic emission, composite fibers previously submitted to a tensile stress absorb selectively UV emission when the polarized laser beam is parallel to the main axis of the fiber. In addition, their photolumincescence is also anisotropic, with a waveguide behavior along the main axis of the fiber. Mechanical properties of these composite fibers are also drastically improved, compared with pure PVA fibers: the longitudinal Young modulus of these fibers is increased from 2 to 6 GPa upon ZnO addition, a value similar to those already observed for composite fibers, prepared either with carbon nanotubes, or V2O5 macroscopic fibers. [less ▲]

Detailed reference viewed: 2 (2 ULg)
Full Text
Peer Reviewed
See detailPhase-Change Materials: Vibrational Softening upon Crystallization and Its Impact on Thermal Properties
Matsunaga, Toshiyuki; Yamada, Noboru; Kojima, Rie et al

in Advanced Functional Materials (2011), 21(12), 2232-2239

Crystallization of an amorphous solid is usually accompanied by a significant change of transport properties, such as an increase in thermal and electrical conductivity. This fact underlines the ... [more ▼]

Crystallization of an amorphous solid is usually accompanied by a significant change of transport properties, such as an increase in thermal and electrical conductivity. This fact underlines the importance of crystalline order for the transport of charge and heat. Phase-change materials, however, reveal a remarkably low thermal conductivity in the crystalline state. The small change in this conductivity upon crystallization points to unique lattice properties. The present investigation reveals that the thermal properties of the amorphous and crystalline state of phase-change materials show remarkable differences such as higher thermal displacements and a more pronounced anharmonic behavior in the crystalline phase. These findings are related to the change of bonding upon crystallization, which leads to an increase of the sound velocity and a softening of the optical phonon modes at the same time. [less ▲]

Detailed reference viewed: 7 (3 ULg)
Full Text
Peer Reviewed
See detailContact-killing polyelectrolyte microcapsules based on chitosan derivatives
Cui, Di; Szarpak, Anna; Pignot-Paintrand, Isabelle et al

in Advanced Functional Materials (2010), 20(19), 3303-3312

A new type of multilayer capsules is designed for use as antibacterial vehicles by taking advantage of the properties of natural polysaccharides. These capsules, prepared by layer-by-layer assembly of ... [more ▼]

A new type of multilayer capsules is designed for use as antibacterial vehicles by taking advantage of the properties of natural polysaccharides. These capsules, prepared by layer-by-layer assembly of hyaluronic acid (HA; see graphic) and quaternized chitosan (QCHI) derivatives onto sacrificial colloidal particles, show distinct killing activities depending on the nature of the polysaccharide on the surface. [less ▲]

Detailed reference viewed: 29 (3 ULg)
Full Text
Peer Reviewed
See detailpH-responsive flower-type micelles formed by a biotinylated poly(2-vinylpyridine)-block-poly(ethylene-oxide)-block-poly(ε-caprolactone) triblock copolymer
Van Butsele, Kathy ULg; Cajot, Sébastien ULg; Van Vlierberghe, Sandra et al

in Advanced Functional Materials (2009), 19(9), 1416-1425

In the present work, a method is proposed to assemble pH-responsive, flower-like micelles that can expose a targeting unit at their periphery upon a decrease in pH. The micelles are composed of a novel ... [more ▼]

In the present work, a method is proposed to assemble pH-responsive, flower-like micelles that can expose a targeting unit at their periphery upon a decrease in pH. The micelles are composed of a novel biotinylated triblock copolymer of poly(-caprolactone)-block-poly(ethylene oxide)-block-poly(2-vinylpyridine) (PCL-b-PEO-b-P2VP) and the non-biotinylated analogue. The block copolymers are synthesized by sequential anionic and ring-opening polymerization. The pH-dependent micellization behaviour in aqueous solution of the triblock copolymers developed is studied using dynamic light scattering, zeta potential, transmission electron microscopy (TEM), and fluorimetric measurements. The shielding of the biotin at neutral pH and their availability at the micelle surface upon protonation is established by TEM and surface plasmon resonance with avidin and streptavidin-coated gold surfaces. The preliminary stealthy behavior of these pH-responsive micelles is examined using the complement activation (CH50) test. [less ▲]

Detailed reference viewed: 112 (37 ULg)
Full Text
Peer Reviewed
See detailSynthesis of amphiphilic copolymers of poly(ethylene oxide) and poly(epsilon-caprolactone) with different architectures, and their role in the preparation of stealthy nanoparticles
Rieger, Jutta ULg; Passirani, Catherine; Benoît, Jean-Pierre et al

in Advanced Functional Materials (2006), 16(11), 1506-1514

Well-defined copolymers of biocompatible poly(epsilon-caprolactone) (PCL) and poly(ethylene oxide) (PEO) are synthesized by two methods. Graft copolymers with a gradient structure are prepared by ring ... [more ▼]

Well-defined copolymers of biocompatible poly(epsilon-caprolactone) (PCL) and poly(ethylene oxide) (PEO) are synthesized by two methods. Graft copolymers with a gradient structure are prepared by ring-opening copolymerization of epsilon-caprolactone (FCL) with a PEO macromonomer of the epsilon CL-type. The epsilon CL polymerization is initiated by a PEO macroinitiator to prepare diblock copolymers. These amphiphilic copolymers are used as stabilizers for biodegradable poly(DL-lactide) (PLA) nanoparticles prepared by a nanoprecipitation technique. The effect of the copolymer characteristic features (architecture, composition, and amount) on the nanoparticle formation and structure is investigated. The average size, size distribution, and stability of aqueous suspensions of the nanoparticles is measured by dynamic light scattering. For comparison, an amphiphilic random copolymer, poly(methyl methacrylate-co-methacrylic acid) (P(MMA-co-MA)), is synthesized. The stealthiness of the nanoparticles is analyzed in relation to the copolymer used as stabilizer. For this purpose, the activation of the complement system by nanoparticles is investigated in vitro using human serum. This activation is much less important whenever the nanoparticles are stabilized by a PEO-containing copolymer rather than by the P(MMA-co-MA) amphiphile. The graft copolymers with a gradient structure and the diblock copolymers with similar macromolecular characteristics (molecular weight and hydrophilicity) are compared on the basis of their capacity to coat PLA nanoparticles and to make them stealthy. [less ▲]

Detailed reference viewed: 40 (12 ULg)
Full Text
Peer Reviewed
See detailA micellar route to ordered arrays of magnetic nanoparticles: From size-selected pure cobalt dots to cobalt-cobalt oxide core-shell systems
Boyen, Hans-Gerd; Kästle, Gerd; Zürn, Klaus et al

in Advanced Functional Materials (2003), 13(5), 359-364

Starting with Co-salt-loaded inverse micelles, which form if the diblock copolymer polystyrene-block-poly(2-vinylpyridine) is dissolved in a selective solvent like toluene and CoCl2) is added to the ... [more ▼]

Starting with Co-salt-loaded inverse micelles, which form if the diblock copolymer polystyrene-block-poly(2-vinylpyridine) is dissolved in a selective solvent like toluene and CoCl2) is added to the solution, monomicellar arrays of such micelles exhibiting a significant hexagonal order can be prepared on top of various substrates with tailored intermicellar distances and structure heights. In order to remove the polymer matrix and to finally obtain arrays of pure Co nanoparticles, the micelles are first exposed to an oxygen plasma, followed by a treatment in a hydrogen plasma. Applying in-situ X-ray photoelectron spectroscopy, it is demonstrated that: 1) The oxygen plasma completely removes the polymer, though conserving the original order of the micellar array. Furthermore, the resulting nanoparticles are entirely oxidized with a chemical shift of the Co 2P(3/2) line pointing to the formation Of Co3O4. 2) By the subsequent hydrogen plasma treatment the nanoparticles are fully reduced to metallic Co. 3) By exposing the pure Co nanoparticles for 100 s to various oxygen partial pressures p(O2), a stepwise oxidation is observed with a still metallic Co core surrounded by an oxide shell. The data allow the extraction of the thickness of the oxide shell as a function of the total exposure to oxygen (p(O2) x time), thus giving the opportunity to control the ferromagnetic-antiferromagnetic composition of an exchange-biased magnetic system. [less ▲]

Detailed reference viewed: 20 (4 ULg)