References of "Gohy, Jean-François"
     in
Bookmark and Share    
Full Text
See detailMetallo-supramolecular micellar gels: a structural study
Mugemana, Clément; Joset, Arnaud ULg; Guillet, Pierre et al

Poster (2013, July 10)

Detailed reference viewed: 9 (2 ULg)
Full Text
See detailMetallo-supramolecular micellar gels: a structural study
Mugemana, Clément; Joset, Arnaud ULg; Guillet, Pierre et al

Conference (2013, May 17)

Detailed reference viewed: 15 (1 ULg)
Full Text
See detailSynthesis in scCO2 of nano-hydrogels for proteins delivery
Alaimo, David ULg; Grignard, Bruno ULg; Fustin, Charles-André et al

Conference (2012, November 14)

Detailed reference viewed: 21 (2 ULg)
Full Text
Peer Reviewed
See detailTocol modified glycol chitosan for the oral delivery of poorly soluble drugs
Duhem, Nicolas; Rolland, Julien; Riva, Raphaël ULg et al

in International Journal of Pharmaceutics (2012), 423(2), 452-460

The aim of this study was to develop tocol derivatives of chitosan able (i) to self-assemble in the gastrointestinal tract and (ii) to enhance the solubility of poorly soluble drugs. Among the derivatives ... [more ▼]

The aim of this study was to develop tocol derivatives of chitosan able (i) to self-assemble in the gastrointestinal tract and (ii) to enhance the solubility of poorly soluble drugs. Among the derivatives synthesized, tocopherol succinate glycol chitosan (GC-TOS) conjugates spontaneously formed micelles in aqueous solution with a critical micelle concentration of 2 μg mL−1. AFM and TEM analysis showed that spherical micelles were formed. The GC-TOS increased water solubility of 2 model class II drugs. GC-TOS loading efficiency was 2.4% (w/w) for ketoconazole and 0.14% (w/w) for itraconazole, respectively. GC-TOS was non-cytotoxic at concentrations up to 10 mg mL−1. A 3.4-fold increase of the apparent permeation coefficient of ketoconazole across a Caco-2 cell monolayer was demonstrated. Tocol polymer conjugates may be promising vehicles for the oral delivery of poorly soluble drugs. [less ▲]

Detailed reference viewed: 29 (12 ULg)
Full Text
See detailStimuli-responsive triblock copolymer for biomedical applications
Sibret, Pierre ULg; Croisier, Florence ULg; Zhao, J. et al

Poster (2010, May 25)

Detailed reference viewed: 14 (2 ULg)
Full Text
See detailMagnetic hybrid based on iron oxide nanoparticles and thermoresponsive block copolymer for biomedical applications
Sibret, Pierre ULg; Aqil, Abdelhafid; Zhao, J. et al

Poster (2010, March 18)

Detailed reference viewed: 24 (2 ULg)
Full Text
Peer Reviewed
See detailSynthesis and pH-dependent micellization of diblock copolymer mixtures
Van Butsele, Kathy ULg; Sibret, Pierre ULg; Fustin, Charles-André et al

in Journal of Colloid & Interface Science (2009), 329(2), 235-243

This work focused on the preparation and the aqueous solution properties of hybrid polymeric micelles consisting of a hydrophobic poly(ε-caprolactone) (PCL) core and a mixed shell of hydrophilic poly ... [more ▼]

This work focused on the preparation and the aqueous solution properties of hybrid polymeric micelles consisting of a hydrophobic poly(ε-caprolactone) (PCL) core and a mixed shell of hydrophilic poly(ethylene oxide) (PEO) and pH-sensitive poly(2-vinylpyridine) (P2VP). The hybrid micelles were successfully prepared by the rapid addition of acidic water to a binary solution of PCL34-b-PEO114 and PCL32-b-P2VP52 diblock copolymers in N,N-dimethylformamide. These micelles were pH-responsive as result of the pH-dependent ionization of the P2VP block. The impact of pH on the self-assembly of the binary mixture of diblocks—thus on the composition, shape, size and surface properties of the micelles—was studied by a variety of experimental techniques, i.e., dynamic and static light scattering, transmission electron microscopy, Zeta potential, fluorescence spectroscopy and complement hemolytic 50 test. [less ▲]

Detailed reference viewed: 66 (19 ULg)
Full Text
Peer Reviewed
See detailSelf-assembly and pH-responsiveness of ABC miktoarm star terpolymers
Van Butsele, Kathy ULg; Fustin, Charles-André; Gohy, Jean-François et al

in Langmuir (2009), 25(1), 107-111

This work deals with the self-assembly in water of ABC miktoarm star terpolymers consisting of hydrophobic poly(-caprolactone), hydrophilic poly(ethylene oxide) (PEO), and pH-sensitive poly(2 ... [more ▼]

This work deals with the self-assembly in water of ABC miktoarm star terpolymers consisting of hydrophobic poly(-caprolactone), hydrophilic poly(ethylene oxide) (PEO), and pH-sensitive poly(2-vinylpyridine) (P2VP). A variety of experimental techniques were used, including dynamic light scattering, transmission electron microscopy, and zeta potential. Special attention was paid to the pH dependency of the supramolecular self-assemblies. A key observation is the capability of the miktoarm terpolymers to form micelles stable over the whole range of pH, although a transition was observed from neutral to highly positively charged nanoobjects upon decreasing pH. [less ▲]

Detailed reference viewed: 32 (7 ULg)
See detailPreparation and characterization of thermoresponsive iron nanoparticles for biomedical applications
Sibret, Pierre ULg; Aqil, Abdelhafid ULg; Gohy, Jean-François et al

Poster (2008, November 28)

Detailed reference viewed: 22 (4 ULg)
Full Text
Peer Reviewed
See detailNormal and frictional forces between surfaces bearing polyelectrolyte brushes
Raviv, Uri; Giasson, Suzanne; Kampf, Nir et al

in Langmuir (2008), 24(16), 8678-8687

Normal and shear forces were measured as a function of surface separation, D, between hydrophobized mica surfaces bearing layers of a hydrophobic−polyelectrolytic diblock copolymer, poly(methyl ... [more ▼]

Normal and shear forces were measured as a function of surface separation, D, between hydrophobized mica surfaces bearing layers of a hydrophobic−polyelectrolytic diblock copolymer, poly(methyl methacrylate)-block-poly(sodium sulfonated glycidyl methacrylate) copolymer (PMMA-b-PSGMA). The copolymers were attached to each hydrophobized surface by their hydrophobic PMMA moieties with the nonadsorbing polyelectrolytic PSGMA tails extending into the aqueous medium to form a polyelectrolyte brush. Following overnight incubation in 10−4 w/v aqueous solution of the copolymer, the strong hydrophobic attraction between the hydrophobized mica surfaces across water was replaced by strongly repulsive normal forces between them. These were attributed to the osmotic repulsion arising from the confined counterions at long-range, together with steric repulsion between the compressed brush layers at shorter range. The corresponding shear forces on sliding the surfaces were extremely low and below our detection limit (±20−30 nN), even when compressed down to a volume fraction close to unity. On further compression, very weak shear forces (130 ± 30 nN) were measured due to the increase in the effective viscous drag experienced by the compressed, sliding layers. At separations corresponding to pressures of a few atmospheres, the shearing motion led to abrupt removal of most of the chains out of the gap, and the surfaces jumped into adhesive contact. The extremely low frictional forces between the charged brushes (prior to their removal) is attributed to the exceptional resistance to mutual interpenetration displayed by the compressed, counterion-swollen brushes, together with the fluidity of the hydration layers surrounding the charged, rubbing polymer segments. [less ▲]

Detailed reference viewed: 21 (0 ULg)
Full Text
Peer Reviewed
See detailCore-Shell-Corona Micelles by PS-b-P2VP-b-PEO Copolymers: Focus on the Water-Induced Micellization Process
Willet, Nicolas ULg; Gohy, Jean-François; Auvray, Loïc et al

in Langmuir (2008), 24(7), 3009-3015

It is now well established that amphiphilic PS-b-P2VP-b-PEO linear triblock copolymers can form multilayered assemblies, thus core-shell-corona (CSC) micelles, in water. Micellization is triggered by ... [more ▼]

It is now well established that amphiphilic PS-b-P2VP-b-PEO linear triblock copolymers can form multilayered assemblies, thus core-shell-corona (CSC) micelles, in water. Micellization is triggered by addition of a small amount of water into a dilute solution of the PS-b-P2VP-b-PEO copolymer in a non-selective organic solvent. However, the phenomena that take place at the very beginning of this process are poorly documented. How these copolymer chains are perturbed by addition of water was investigated in this work by light and neutron scattering techniques and transmission electron microscopy. It was accordingly possible to determine the critical water concentration (CWC), the compactness of the nano-objects in solution, their number of aggregation, and their hydrodynamic diameter at each step of the micellization process. [less ▲]

Detailed reference viewed: 82 (18 ULg)
Full Text
Peer Reviewed
See detailFast multiresponsive micellar gels from a smart ABC triblock copolymer
Willet, Nicolas ULg; Gohy, Jean-François; Lei, Liangcai et al

in Angewandte Chemie (International ed. in English) (2007), 46(42), 7988-7992

The triblock copolymer PS-b-P2VP-b-PEO undergoes simultaneous micellization and gelation, leading to high-storage-modulus materials that have fast responses to pH value, temperature, ionic strength, and ... [more ▼]

The triblock copolymer PS-b-P2VP-b-PEO undergoes simultaneous micellization and gelation, leading to high-storage-modulus materials that have fast responses to pH value, temperature, ionic strength, and shearing. The gel has a hierarchical structure with spherical core-shell-corona micelles, which, in turn, pack closely into an ordered cubic structure. [less ▲]

Detailed reference viewed: 56 (19 ULg)
Full Text
Peer Reviewed
See detailMicellization of Poly(2-oxazoline)-Based Quasi-Diblock Copolymers on Surfaces
Fustin, Charles-André; Lefèvre, Nathalie ULg; Hoogenboom, Richard et al

in Macromolecular Chemistry and Physics (2007), 208

The micellization on surfaces of two series of quasi-diblock copoly(2-oxazoline)s consisting of 2-phenyl-2-oxazoline (PhOx) segments linked to either 2-methyl-2-oxazoline (MeOx) or 2-ethyl-2-oxazoline ... [more ▼]

The micellization on surfaces of two series of quasi-diblock copoly(2-oxazoline)s consisting of 2-phenyl-2-oxazoline (PhOx) segments linked to either 2-methyl-2-oxazoline (MeOx) or 2-ethyl-2-oxazoline (EtOx) segments is investigated in detail. Those micelles are not preexisting in the initial ethanol solution but are formed during the spin-coating process by the evaporation of the solvent inducing the precipitation of the less soluble PhOx segments. The morphology and size of the surface micelles vary according to the fraction of PhOx in the copolymers. Moreover, it is demonstrated that the chemical nature of the more soluble MeOx or EtOx segments also has an influence on the morphology of the resulting surface micelles. [less ▲]

Detailed reference viewed: 17 (4 ULg)
Full Text
See detailpH-responsive micelles in dilute and gel-like media
Willet, Nicolas ULg; Leyh, Bernard ULg; Gohy, Jean-François et al

Conference (2006, June)

Detailed reference viewed: 4 (0 ULg)
Full Text
Peer Reviewed
See detailDependence of the structure of core-shell-corona micelles on the composition of water/toluene mixtures
Lei, Liangcai; Gohy, Jean-François; Willet, Nicolas ULg et al

in Polymer (2006), 47(8), 2723-2727

The poly(styrene)-block-poly(2-vinylpyridine)-block-poly(ethyleile oxide) triblock copolymer. PS200-b-P2VP(140)-b-PEO590, where the subscripts refer to the average degrees of polymerisation of the ... [more ▼]

The poly(styrene)-block-poly(2-vinylpyridine)-block-poly(ethyleile oxide) triblock copolymer. PS200-b-P2VP(140)-b-PEO590, where the subscripts refer to the average degrees of polymerisation of the constitutive blocks, has been dissolved in water/toluene mixtures with a large range of composition, i.e. in (i) toluene added with a small amount of water. (ii) water-in-toluene emulsion forming mixtures, (iii) toluene-in-water emulsion forming mixtures, and (iv) water added with a small amount of toluene. These Solutions have been cast on a carbon-coated copper grid, and the morphology of the dried copolymer deposition has been observed by transmission electron microscopy. Rod-like aggregates with a core-shell-corona micellar structure are formed in cases (i) and (iv). Nevertheless, PEO is the core and PS is the corona in case (i). whereas the reverse situation prevails in case (iv). When an emulsion is the precursor of the dried copolymer aggregates, either onion-like structures (case ii) or vesicles mixed with more complex aggregates are formed (case iii). These structures are thought to reflect the self-organization of the PS200-b- P2VP(140)-b-PEO590 copolymer at the water/toluene interface of the water-in-toluene and toluene-in-water emulsions. respectively. [less ▲]

Detailed reference viewed: 47 (2 ULg)
Full Text
Peer Reviewed
See detailDithioesters and Trithiocarbonates as Anchoring Groups for the "Grafting-To" Approach
Duwez, Anne-Sophie ULg; Guillet, Pierre; Collard, Catheline et al

in Macromolecules (2006), 39

Detailed reference viewed: 39 (2 ULg)
Full Text
Peer Reviewed
See detailTuning the Hydrophilicity of Gold Nanoparticles Templated in Star-Block Copolymers
Fustin, Charles-André; Colard, Catheline; Filali, Mariam et al

in Langmuir (2006), 22

We report on a simple procedure to tune the hydrophilicity of hybrid gold nanoparticles. The nanoparticles have been prepared in the core of a poly(ethylene glycol)-block-poly( -caprolactone) (PEG-b-PCL ... [more ▼]

We report on a simple procedure to tune the hydrophilicity of hybrid gold nanoparticles. The nanoparticles have been prepared in the core of a poly(ethylene glycol)-block-poly( -caprolactone) (PEG-b-PCL) five-arm star block copolymer. A hydrophilic corona was then added to these hybrid gold nanoparticles by direct chemisorption of trithiocarbonate-containing poly(acrylic acid) chains. These polymers were synthesized by RAFT polymerization with a trithiocarbonate as the chain-transfer agent. The efficiency of the grafting was evidenced by TEM, AFM, and DLS and by the successful transfer of these nanoparticles from organic solvent to water. [less ▲]

Detailed reference viewed: 19 (1 ULg)