References of "Alaimo, David"
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See detailBlock, random and palm-tree amphiphilic fluorinated copolymers: controlled synthesis, surface activity and use as dispersion polymerization stabilizers
Alaimo, David ULg; Beigbeder, Alexandre; Dubois, Philippe et al

in Polymer Chemistry (2014), 5(18), 5273-5282

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See detailTunable self-assembled nanogels composed of well-defined thermoresponsive hyaluronic acid-polymer conjugates
Jing, Jing; Alaimo, David ULg; De Vlieghere, Elly et al

in Journal of Materials Chemistry B (2013), 1(32), 3883-3887

Here we report that grafting temperature-responsive polymers onto hyaluronic acid allows temperature-induced self-assembly into nanogels with tunable size. These nanogels can be easily loaded with ... [more ▼]

Here we report that grafting temperature-responsive polymers onto hyaluronic acid allows temperature-induced self-assembly into nanogels with tunable size. These nanogels can be easily loaded with hydrophobic molecules and hold potential for anti-cancer drug delivery towards human ovarian cancer cells. [less ▲]

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See detailSurface activity of a fluorinated carbohydrate ester in water/carbon dioxide emulsions
Favrelle, Audrey; Boyère, Cédric ULg; Tran, Kien My et al

in Journal of Colloid & Interface Science (2013), 398

The water/carbon dioxide (W/CO2) interfacial activity and emulsifying capacity of hydrocarbon and fluorinated carbohydrate esters are investigated of the first time and compared to the performance of ... [more ▼]

The water/carbon dioxide (W/CO2) interfacial activity and emulsifying capacity of hydrocarbon and fluorinated carbohydrate esters are investigated of the first time and compared to the performance of sodium-bis(2-ethylhexyl)sulfosuccinate (AOT). The reduction of the W/CO2 interfacial tension was measured using a pendant drop tensiometer equipped with a cell view pressurized with CO2 at 80 bar and 45 °C. It was found that the interface stabilization improved in the order AOT < 6-O-myristoyl mannose < 6-O-(2H,2H,3H,3H-perfluoroundecanoyl)-D-mannose. In the latter case, a drastic reduction of the W/CO2 interfacial tension was observed (85% reduction, interfacial tension at the equilibrium = 3.6 mN/m), which emphasizes the advantage of using a fluorinated CO2-philic tail and the potential of sugars as hydrophilic head. The formulation of stable W/CO2 emulsions was also achieved using the fluorinated mannose derivative. This study paves the way to the design of a novel class of competitive surface active agents for W/CO2 emulsions. [less ▲]

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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)

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See detailα-Acetal, ω-alkyne poly(ethylene oxide) as a versatile building block for the synthesis of glycoconjugated graft-copolymers suited for targeted drug delivery
Freichels, Hélène; Alaimo, David ULg; Auzély-Velty, Rachel et al

in Bioconjugate Chemistry (2012), 23(9), 1740-1752

α-Acetal, ω-alkyne poly(ethylene oxide) was synthesized as building block of glycoconjugated poly(ε-caprolactone)-graft-poly(ethylene oxide) (PCL-g-PEO) copolymers. The alkyne group is indeed instrumental ... [more ▼]

α-Acetal, ω-alkyne poly(ethylene oxide) was synthesized as building block of glycoconjugated poly(ε-caprolactone)-graft-poly(ethylene oxide) (PCL-g-PEO) copolymers. The alkyne group is indeed instrumental for the PEGylation of a poly(α-azido-ε-caprolactone-co-ε-caprolactone) copolymer by the Huisgen’s 1,3 dipolar cycloaddition, i.e., a click reaction. Moreover, deprotection of the acetal end-group of the hydrophilic PEO grafts followed by reductive amination of the accordingly formed aldehyde with an aminated sugar is a valuable strategy of glycoconjugation of the graft copolymer, whose micelles are then potential. A model molecule (fluoresceinamine) was first considered in order to optimize the experimental conditions for the reductive amination. These conditions were then extended to the decoration of the graft copolymer micelles with mannose, which is a targeting agent of dendritic cells and macrophages. The bioavailability of the sugar units at the surface of micelles was investigated by surface plasmon resonance (SPR). The same question was addressed to nanoparticles stabilized by the graft copolymer. Enzyme linked lectin assay (ELLA) confirmed the availability of mannose at the nanoparticle surface. [less ▲]

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See detailNew glucose-responsive polyelectrolyte microcapsules
Alaimo, David ULg; Detrembleur, Christophe ULg; Auzély-Velty, Rachel et al

Poster (2011, December 06)

Diabetes is a disorder of glucose regulation, characterized by an accumulation of glucose in the blood. The breakdown of glucose regulation can be attributed to the pancreas’s inability to secrete insulin ... [more ▼]

Diabetes is a disorder of glucose regulation, characterized by an accumulation of glucose in the blood. The breakdown of glucose regulation can be attributed to the pancreas’s inability to secrete insulin or to the body’s inability to properly use it. The usual treatment for type 1 diabetes consists in multiple subcutaneous insulin injections, daily administered using needles, insulin pen or insulin pump. However, this method doesn’t maintain normoglycemia and can lead to complications such as limb amputation, blindness, and kidney failure. To avoid such abnormal episodes, scientists imagined smart systems which are able to regulate the glucose level by themselves. During the past decades, a large variety of micro- and nanocarriers have been developed in order to improve efficiency, availability and toxicity profiles of drugs. In this field, stimuli-responsive polymer multilayers have attracted great scientific interest because of their potential applications as controlled delivery or release systems, for chemicals and drugs. A category of stimuli-responsive materials is able to sense glucose and respond to it by a modification of their porosity, leading to a release of insulin. The objective of this work was to investigate the formation of glucose responsive hollow microcapsules (5 microns) made of polyelectrolyte copolymers. These copolymers are composed of carbohydrate-sensitive functions, such as boronic acid and diols (PVOH), known for forming reversible covalent ether bond. In presence of carbohydrates such as glucose, the ether bonds will be reversibly broken and, consequently, the porosity of the glucose particles will change. Therefore, polyelectrolyte copolymers were synthesized by control radical polymerization, i.e. reversible addition-fragmentation chain transfer (RAFT, polyboronic acid) and cobalt-mediated radical polymerization (CMRP, PVOH). Using these polyelectrolytes as polyanions and poly(allylamine) (PAH) as a polycation, we undertook the formation of layer-by-layer capsules starting with a template of CaCO3microparticles which can be dissolved with EDTA leading to the formation of hollow microcapsules. Bovin serum albumin isothiocyanate (BSA-FITC) was used to fill the CaCO3microparticles and to determine the porosity of the resulting capsules in function of the glucose concentration. The sugar-dependent porosity is investigated by following the release of encapsulated BSA-FITC by spectro-fluoroscopy. [less ▲]

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See detailGlucose-responsive layer-by-layer microcapsules as self-regulated insulin delivery system
Alaimo, David ULg; Detrembleur, Christophe ULg; Auzély-Velty, Rachel et al

Poster (2011, September 03)

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See detailNew fluorinated surfactant for nanogels preparation in supercritical CO2
Alaimo, David ULg; Beigbeder, Alexandre; Dubois, Philippe et al

Poster (2011, April 29)

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See detailNew fluorinated surfactants for nanogels preparation in supercritical CO2
Alaimo, David ULg; Beigbeder, Alexandre; Dubois, Philippe et al

Poster (2010, November 29)

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See detailGlucose-responsive layer-by-layer microcapsules: a potential route to self-regulated insulin delivery
Alaimo, David ULg; Detrembleur, Christophe ULg; Auzély-Velty, Rachel et al

Conference (2010, May 25)

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See detailSynthesis of glucose-responsive hollow capsules
Alaimo, David ULg; Detrembleur, Christophe ULg; Auzély-Velty, Rachel et al

Poster (2009, December 07)

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See detailPréparation de nouveaux copolymères amphiphiles mannosylés d'architecture greffée et caractérisation par QCM-D
Freichels, Hélène ULg; Broze, Guy; Alaimo, David ULg et al

Conference (2009, October 14)

Durant les dernières décennies, le domaine pharmaceutique s’est intéressé aux micelles et nanoparticules polymères celles-ci pouvant être utilisées comme vecteurs à libération contrôlée. Dans ce domaine ... [more ▼]

Durant les dernières décennies, le domaine pharmaceutique s’est intéressé aux micelles et nanoparticules polymères celles-ci pouvant être utilisées comme vecteurs à libération contrôlée. Dans ce domaine, des copolymères amphiphiles combinant le poly(oxyde d’éthylène) (POE), polymère possédant des propriétés répulsives vis-à-vis des protéines plasmiques, et la poly-epsilon-caprolactone (PCL), un polyester aliphatique, polymère hydrophobe biocompatible et biodégradable permettant l’incorporation d’un principe actif hydrophobe, sont d’excellents candidats pour cette d’application. Jusqu’à présent, ce type de copolymère amphiphile principalement étudié est d’architecture linéaire. Récemment, notre laboratoire a développé une stratégie permettant la préparation de nouveaux copolymères greffés, composés d’un squelette principal de PCL et de greffons de POE. De plus, des agents de ciblage peuvent être introduits à l’extrémité du POE de ces copolymères amphiphiles, faisant de ceux-ci des candidats idéaux comme vecteur de troisième génération, permettant un ciblage spécifique au sein même de l’organisme. Le mannose est un agent intéressant, car il est reconnu à la surface des cellules dendritiques. Dans ce travail, la préparation de copolymères greffés fonctionnalisés par du mannose est décrite. La présence de mannose à la surface des micelles a d’abord été mise en évidence par test ELLA (Enzyme Linked Lectin Assay). Ensuite une étude plus approfondie a été réalisée par QCM-D (Microbalance à Cristal de Quartz avec Dissipation). Cette technique originale permet de mettre en évidence l’interaction entre la lectine immobilisée sur la surface du cristal de la microbalance et le mannose exposés à la périphérie des micelles du copolymère. [less ▲]

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See detailNew fluorinated surfactants for nanogels preparation
Alaimo, David ULg; Rieger, Jutta; Beigbeder, Alexandre et al

Conference (2009, June 18)

A series of novel fluorinated amphiphilic stabilizers of different architecture (diblock, grafted, or palm tree copolymers) were successfully prepared by reversible addition-fragmentation chain transfer ... [more ▼]

A series of novel fluorinated amphiphilic stabilizers of different architecture (diblock, grafted, or palm tree copolymers) were successfully prepared by reversible addition-fragmentation chain transfer and used as stabilizers for the dispersion polymerization of 2-hydroxyethyl methacrylate (HEMA) in fluorinated solvent, namely alpha,alpha,alpha-trifluorotoluene (TFT). The effect of the amount and the architecture of the copolymer on the size and the stabilization of the particles was studied. Whatever the experimental conditions, scanning electron microscopy showed the formation of submicronic (typically about 300 nm) spherical particles, with a narrow size distribution. The principal difference emerges from the concentration of surfactant. Indeed, at higher copolymer concentration, smaller and less aggregated particles were produced. These results were confirmed by dynamic light scattering but these measurements also revealed the presence of larger aggregates (1,5 micrometer). Furthermore, the surfactant properties of the copolymers were investigated by measuring the interfacial tension at the H2O/TFT interface, and the results were correlated to their stabilizing efficiency in the dispersion polymerization of HEMA. [less ▲]

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See detailPegylated thermally responsive block copolymer micelles and nanogels via in situ RAFT aqueous dispersion polymerization
Rieger, Jutta ULg; Grazon, Chloé; Charleux, Bernadette et al

in Journal of Polymer Science. Part A, Polymer Chemistry (2009), 47(9), 2373-2390

A very straightforward approach was developed to synthesize pegylated thermoresponsive core-shell nanoparticles in a minimum of steps, directly in water. It is based on RAFT-controlled radical ... [more ▼]

A very straightforward approach was developed to synthesize pegylated thermoresponsive core-shell nanoparticles in a minimum of steps, directly in water. It is based on RAFT-controlled radical crosslinking copolymerization of N,N-diethylacrylamide (DEAAm) and N,N-methylene bisacrylamide (MBA) in aqueous dispersion polymerization. Because DEAAm is water-soluble and poly(N,N-diethylacrylamide) (PDEAAm) exhibits a lower critical solution temperature at 32 °C, the initial medium was homogeneous, whereas the polymer formed a separate phase at the reaction temperature. The first macroRAFT agent was a surface-active trithiocarbonate based on a hydrophilic poly(ethylene oxide) block and a hydrophobic dodecyl chain. It was further extented with N,N-dimethylacrylamide (DMAAm) to target macroRAFT agents with increasing chain length. All macroRAFT agents provided excellent control over the aqueous dispersion homopolymerization of DEAAm. When they were used in the radical crosslinking copolymerization of DEAAm and MBA, the stability and size of the resulting gel particles were found to depend strongly on the chain length of the macroRAFT agent, on the concentrations of both the monomer and the crosslinker, and on the process (one step or two steps). The best-suited experimental conditions to reach thermosensitive hydrogels with nanometric size and well-defined surface properties were determined. [less ▲]

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See detailNew fluorinated surfactant for nanogels preparation
Alaimo, David ULg; Rieger, Jutta; Beigbeder, Alexandre et al

Conference (2009, March 19)

A series of novel fluorinated amphiphilic stabilizers of different architecture (diblock, grafted, or palm tree copolymers) were successfully prepared by reversible addition-fragmentation chain transfer ... [more ▼]

A series of novel fluorinated amphiphilic stabilizers of different architecture (diblock, grafted, or palm tree copolymers) were successfully prepared by reversible addition-fragmentation chain transfer and used as stabilizers for the dispersion polymerization of 2-hydroxyethyl methacrylate (HEMA) in fluorinated solvent, namely alpha,alpha,alpha-trifluorotoluene (TFT). The effect of the amount and the architecture of the copolymer on the size and the stabilization of the particles was studied. Whatever the experimental conditions, scanning electron microscopy showed the formation of submicronic (typically about 300 nm) spherical particles, with a narrow size distribution. The principal difference emerges from the concentration of surfactant. Indeed, at higher copolymer concentration, smaller and less aggregated particles were produced. These results were confirmed by dynamic light scattering but these measurements also revealed the presence of larger aggregates (1,5 micrometer). Furthermore, the surfactant properties of the copolymers were investigated by measuring the interfacial tension at the H2O/TFT interface, and the results were correlated to their stabilizing efficiency in the dispersion polymerization of HEMA. [less ▲]

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See detailThermally-responsive nanogels by RAFT-mediated aqueous dispersion polymerization
Rieger, Jutta ULg; Grazon, Chloé; Bui, Chuong et al

in PMSE preprints (2009), 101

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See detailAmphiphilic poly(ethylene oxide) macromolecular RAFT agent as a stabilizer and control agent in ab Initio batch emulsion polymerization
Rieger, Jutta ULg; Stoffelbach, François; Bui, Chuong et al

in Macromolecules (2008), 41(12), 4065-4068

Detailed reference viewed: 77 (15 ULg)
See detailTrithiocarbonate (macro) RAFt agents for the preparation of polymeric nanomaterials in homogeneous and heterogeneous media
Rieger, Jutta; Alaimo, David ULg; Carron, Amélie et al

Poster (2007, August 31)

Detailed reference viewed: 33 (3 ULg)