References of "Jérôme, Christine"
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See detailReversible TAD chemistry as a convenient tool for the design of (re)processable PCL-based shape-memory materials
Defize, Thomas ULg; Riva, Raphaël ULg; Thomassin, Jean-Michel ULg et al

in Macromolecular Rapid Communications (2017), 38(1), 1600517

A chemically cross-linked but remarkably (re)processable shape-memory polymer (SMP) is designed by cross-linking poly(ε -caprolactone) (PCL) stars via the efficient triazolinedione click chemistry, based ... [more ▼]

A chemically cross-linked but remarkably (re)processable shape-memory polymer (SMP) is designed by cross-linking poly(ε -caprolactone) (PCL) stars via the efficient triazolinedione click chemistry, based on the very fast and reversible Alder– ene reaction of 1,2,4-triazoline-3,5-dione (TAD) with indole compounds. Typically, a six-arm star-shaped PCL function- alized by indole moieties at the chain ends is melt-blended with a bisfunctional TAD, directly resulting in a cross-linked PCL-based SMP without the need of post-curing treatment. As demonstrated by the stress relaxation measurement, the labile character of the TAD–indole adducts under stress allows for the solid-state plasticity reprocessing of the permanent shape at will by compression molding of the raw cross-linked material, while keeping excellent shape-memory properties. [less ▲]

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See detailDevelopment and evaluation of injectable nanosized drug delivery systems for apigenin
Karim, Reatul ULg; Palazzo, Claudio ULg; Laloy, Julie et al

in International Journal of Pharmaceutics (2017)

The purpose of this study was to develop different injectable nanosized drug delivery systems (NDDSs) i.e. liposome, lipid nanocapsule (LNC) and polymeric nanocapsule (PNC) encapsulating apigenin (AG) and ... [more ▼]

The purpose of this study was to develop different injectable nanosized drug delivery systems (NDDSs) i.e. liposome, lipid nanocapsule (LNC) and polymeric nanocapsule (PNC) encapsulating apigenin (AG) and compare their characteristics to identify the nanovector(s) that can deliver the largest quantity of AG while being biocompatible. Two liposomes with different surface characteristics (cationic and anionic), a LNC and a PNC were prepared. A novel tocopherol modified poly(ethylene glycol)-b-polyphosphate block-copolymer was used for the first time for the PNC preparation. The NDDSs were compared by their physicochemical characteristics, AG release, storage stability, stability in serum, complement consumption and toxicity against a human macrovascular endothelial cell line (EAhy926). The diameter and surface charge of the NDDSs were comparable with previously reported injectable nanocarriers. The NDDSs showed good encapsulation efficiency and drug loading. Moreover, the NDDSs were stable during storage and in fetal bovine serum for extended periods, showed low complement consumption and were non-toxic to EAhy926 cells up to high concentrations. Therefore, they can be considered as potential injectable nanocarriers of AG. Due to less pronounced burst effect and extended release characteristics, the nanocapsules could be favorable approaches for achieving prolonged pharmacological activity of AG using injectable NDDS. [less ▲]

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See detailPhotoreversibility and biocompatibility of polydimethylsiloxane-coumarin as adjustable intraocular lens material
Jellali, Rachid; Bertrand, Virginie ULg; Alexandre, Michaël et al

in Macromolecular Bioscience (2017)

Polydimethylsiloxane (PDMS) constitutes an interesting material for a variety of biomed- ical applications, especially as intraocular lenses (IOLs), for its excellent transparency. In this work, a ... [more ▼]

Polydimethylsiloxane (PDMS) constitutes an interesting material for a variety of biomed- ical applications, especially as intraocular lenses (IOLs), for its excellent transparency. In this work, a photoreversible PDMS-coumarin network, whose shape and properties can be adjusted postoperatively in a noninvasive manner, is developed. The synthesis of PDMS-cou- marin is achieved by amidation of a coumarin acid chloride derivative with amine-function- alized PDMSs. Under exposure of λ > 300 nm, these polymers can be cured by dimerization of coumarin. The cured polymers can be uncrosslinked via photocleavage of cyclobutane dimers upon illumination at λ < 290 nm. The diffusion of linear PDMSs in a crosslinked network and the controlled shape modification are studied, which demonstrate that these polymers are good candidates for adjustable IOL application. IOL disks prepared from these materials show high hydrophobicity and good transparency. In vitro cytotoxicity, lens epithelial cell adhesion assays, and rabbit host reaction against implanted disks demonstrate the biocompatibility of the polymer. [less ▲]

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See detailCurrent manufacturing processes of drug-eluting sutures
Champeau, Mathilde; Thomassin, Jean-Michel ULg; Tasaing, Thierry et al

in Expert Opinion on Drug Delivery (2017)

Introduction: Drug-eluting sutures represent the next generation of surgical sutures since they fulfill their mechanical functions but also deliver the drug in their vicinity after implantation. These ... [more ▼]

Introduction: Drug-eluting sutures represent the next generation of surgical sutures since they fulfill their mechanical functions but also deliver the drug in their vicinity after implantation. These implants are produced by a variety of manufacturing processes. Drug-eluting sutures represent the next generation of surgical sutures since they fulfill their mechanical functions but also deliver the drug in their vicinity after implantation. These implants are produced by a variety of manufacturing processes. Two general approaches can be followed: (i) the ones that add the API into the material during the manufacturing process of the suture and (ii) the ones that load the API to an already manufactured suture. Areas covered: This review provides an overview of the current manufacturing processes for drug- eluting suture production and discusses their benefits and drawbacks depending on the type of drugs. The mechanical properties and the drug delivery profile of drug-eluting sutures are highlighted since these implants must fulfill both criteria. Expert opinion: For limited drug contents, melt extrusion and electrospinning are the emerging processes since the drug is added during the suture manufacture process. Advantageously, the drug release profile can be tuned by controlling the processing parameters specific to each process and the composition of the drug-containing polymer. If high drug content is targeted, the coating or grafting of a drug layer on a pre-manufactured suture allows for preservation of the tensile strength requirements of the suture. [less ▲]

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See detailOrganocatalyzed coupling of carbon dioxide with epoxides for the synthesis of cyclic carbonates: catalyst design and mechanistic studies
Alves, Margot ULg; Grignard, Bruno ULg; Méreau, Raphaël et al

in Catalysis Science & Technology (2017), 7

The coupling of carbon dioxide (CO2) with epoxides with the formation of cyclic carbonates is a highly attractive 100% atom economy reaction. It represents a greener and safer alternative to the ... [more ▼]

The coupling of carbon dioxide (CO2) with epoxides with the formation of cyclic carbonates is a highly attractive 100% atom economy reaction. It represents a greener and safer alternative to the conventional synthesis of cyclic carbonates from diols and toxic phosgene. Today, cyclic carbonates find many applications as intermediates for fine chemicals synthesis, as electrolytes in Li-ion batteries, and polar aprotic solvents, but also serve for the synthesis of important polymers such as polycarbonates and polyurethanes. In view of their broad scope and their strong economic potential, there is a strong need to improve their synthesis and decrease their production costs. However, CO2 is a thermodynamically stable molecule, the use of catalysts is therefore mandatory for activating and facilitating the CO2/epoxide coupling reaction in a selective manner and under mild conditions. Recently organocatalysts deserved more and more interest in this field, and are viewed as alternatives to metal-based ones. Enormous progress has been made these last years to boost their performances, and some organocatalysts are now very competitive, cheap, readily available and exhibit good chemical stability towards moisture, water and air. This review is focusing on the recent advances in the development of metal-free organocatalysts for the synthesis of cyclic carbonates by CO2/epoxide coupling. Most of the state-of-the art organocatalysts used for this reaction are discussed, with a special emphasis to highlight the various routes employed to boost their performances. Their mode of action is also reported based on mechanistic considerations, supported by density functional theory (DFT) calculations that are becoming essential tools for modern catalysts design. Such detailed understanding of the mechanisms involving CO2 transformation should pave the way towards the definition of new modes of activation for converting CO2 with a large scope of substrates into various chemicals, monomers and polymers. [less ▲]

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See detailIn vitro evaluation of biocompatibility of uncoated thermally reduced graphene and carbon nanotube-loaded PVDF membranes with adult neural stem cell-derived neurons and glia
Defteralı, Çağla; Verdejo, Raquel; Majeed, Shahid et al

in Frontiers in Bioengineering and Biotechnology (2016), 4(n° 64),

Graphene, graphene-based nanomaterials (GBNs), and carbon nanotubes (CNTs) are being investigated as potential substrates for the growth of neural cells. However, in most in vitro studies, the cells were ... [more ▼]

Graphene, graphene-based nanomaterials (GBNs), and carbon nanotubes (CNTs) are being investigated as potential substrates for the growth of neural cells. However, in most in vitro studies, the cells were seeded on these materials coated with various proteins implying that the observed effects on the cells could not solely be attributed to the GBN and CNT properties. Here, we studied the biocompatibility of uncoated thermally reduced graphene (TRG) and poly(vinylidene fluoride) (PVDF) membranes loaded with multi-walled CNTs (MWCNTs) using neural stem cells isolated from the adult mouse olfactory bulb (termed aOBSCs). When aOBSCs were induced to differentiate on coverslips treated with TRG or control materials (polyethyleneimine-PEI and polyornithine plus fibronectin- PLO/F) in a serum-free medium, neurons, astrocytes, and oligodendrocytes were generated in all conditions, indicating that TRG permits the multi-lineage differentiation of aOBSCs. However, the total number of cells was reduced on both PEI and TRG. In a serum-containing medium, aOBSC-derived neurons and oligodendrocytes grown on TRG were more numerous than in controls; the neurons developed synaptic boutons and oligodendrocytes were more branched. In contrast, neurons growing on PVDF membranes had reduced neurite branching, and on MWCNTs-loaded membranes oligodendrocytes were lower in numbers than in controls. Overall, these findings indicate that uncoated TRG may be biocompatible with the generation, differentiation, and maturation of aOBSC-derived neurons and glial cells, implying a potential use for TRG to study functional neuronal networks. [less ▲]

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See detailPolyphosphoesters: new trends in synthesis and drug delivery applications
Ergül, Zeynep ULg; Jérôme, Christine ULg

in Macromolecular Bioscience (2016), 16(12), 1745-1761

Polymers with repeating phosphoester linkages in the backbone are biodegradable materials that emerge as a promising class of novel biomaterials, especially in the field of drug delivery systems. In ... [more ▼]

Polymers with repeating phosphoester linkages in the backbone are biodegradable materials that emerge as a promising class of novel biomaterials, especially in the field of drug delivery systems. In contrast to aliphatic polyesters, the pentavalency of the phosphorus atom offers a large diversity of structures and as a consequence a wide range of properties for these mate- rials. In this paper, it is focused on the synthesis of well-defined polyphosphoesters (PPEs) by organocatalyzed ring-opening polymerization, improving the functionalities by combination with click reactions, degrada- tion of functional PPEs and their cytotoxicity, and inputs for applications in drug delivery. [less ▲]

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See detailProtein encapsulation and release from PEO-b-polyphosphoester templated calcium carbonate particles
Ergül, Zeynep ULg; Cordonnier, Thomas; Debuigne, Antoine ULg et al

in International Journal of Pharmaceutics (2016), 513

Calcium carbonate particles are promising candidates as proteins carriers for their controlled delivery in the body. The present paper aims at investigating the protein encapsulation by in situ ... [more ▼]

Calcium carbonate particles are promising candidates as proteins carriers for their controlled delivery in the body. The present paper aims at investigating the protein encapsulation by in situ precipitation of calcium carbonate particles prepared by a process based on supercritical CO2 and using a new type of degradable well-defined double hydrophilic block copolymers composed of poly(ethylene oxide) and polyphosphoester blocks acting as templating agent for the calcium carbonate. For this study, lysozyme was chosen as a model for therapeutic protein for its availability and ease of detection. It was found that by this green process, loading into the CaCO3 microparticles with a diameter about 2 mm can be obtained as determined by scanning electron microscopy. A protein loading up to 6.5% active lysozyme was measured by a specific bioassay (Micrococcus lysodeikticus). By encapsulating fluorescent-labelled lysozyme (lysozyme-FITC), the confocal microscopy images confirmed its encapsulation and suggested a core–shell distribution of lysozyme into CaCO3, leading to a release profile reaching a steady state at 59% of release after 90 min. [less ▲]

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See detailHot-Melt Extrusion as a Continuous Manufacturing Process to Form Ternary Cyclodextrin Inclusion Complexes
Thiry, Justine ULg; Krier, Fabrice; Ratwatte, Shenelka et al

Poster (2016, November 16)

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See detailPolyhydroxyurethane hydrogels: synthesis and characterizations
Gennen, Sandro ULg; Grignard, Bruno ULg; Thomassin, Jean-Michel ULg et al

in European Polymer Journal (2016), 84

Hydrogels based on polyurethane (PU) are promising (bio-) materials because of their bio- compatibility, biodegradation and excellent mechanical properties. In this publication, polyurethane hydrogels ... [more ▼]

Hydrogels based on polyurethane (PU) are promising (bio-) materials because of their bio- compatibility, biodegradation and excellent mechanical properties. In this publication, polyurethane hydrogels were produced for the first time by a non-isocyanate route by solvent-free step-growth copolymerization between a CO2-sourced hydrophilic polyethy- lene glycol bi-cyclic carbonate with diamines in the presence of a cross-linker. Kinetic of poly(hydroxyurethane) (PHU) synthesis was monitored by ATR-IR and the chemical cross-linking was confirmed by rheology and gel contents measurements. Hydrogels were obtained by immersion of PHUs in water and the influence of the diamine/cross-linker ratio and the nature of diamine on the water swelling and compression properties (compression modulus, strain and stress at break) of PHU hydrogels was evaluated. Additionally, the compression properties of the hydrogels were improved by the addition of Montmorillonite as nanofiller in the PHU formulation. This work opens new application fields for CO2-sourced PHUs. [less ▲]

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See detailSurface- and redox-active multifunctional polyphenol-derived poly(ionic liquid)s: controlled synthesis and characterization
Patil, Nagaraj ULg; Cordella, Daniela; Aqil, Abdelhafid ULg et al

in Macromolecules (2016), 49(20), 7676-7691

Combining the redox activity and remarkable adhesion propensity of polyphenols (such as catechol or pyrogallol) with the numerous tunable properties of poly(ionic liquid)s (PILs) is an attractive route to ... [more ▼]

Combining the redox activity and remarkable adhesion propensity of polyphenols (such as catechol or pyrogallol) with the numerous tunable properties of poly(ionic liquid)s (PILs) is an attractive route to design inventive multifunctional macro-molecular platforms. In this contribution, we describe the first synthesis of a novel family of structurally well-defined PILs functionalized with catechol/pyrogallol/phenol pendants by organometallic-mediated radical polymerization (OMRP) using an alkyl−cobalt(III) complex as initiator and mediating agent. The living character of the chains is also exploited to produce di-and triblock PILs, and the facile counteranion exchange reactions afforded a library of PILs-bearing free phenol/catechol/pyrogallol moieties. Electrochemical investigations of catechol/pyrogallol-derived PILs in aqueous medium demonstrated the characteristic catechol to o-quinone transformations, whereas, quasi-reversible doping/undoping with supporting electrolyte cations (Li + /tetrabutylammonium +) has been observed in organic media, suggesting a bright future for this new family of redox-active PILs as cathode material for secondary energy storage devices. Also, pendant catechol/pyrogallol groups mediated sustained anchoring onto the gold surface conferred PILs properties to the interface. As a proof-of-concept, both the adsorption and inhibition of proteins on polymer modified surfaces have been demonstrated in real time using the quartz crystal microbalance with dissipation technique. The exquisite physicochemical tunability of these innovative surface-and redox-active PILs makes them excellent candidates for a broad range of potential applications, including " smart surfaces " and electrochemical energy storage devices. [less ▲]

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See detailDesign and synthesis of Fe2O3 nanoparticles/N-doped porous carbon structures as high performance electrode for lithium ion battery
Alkarmo, Walid ULg; Ouhib, Farid ULg; Aqil, Abdelhafid ULg et al

Poster (2016, October 13)

Thanks to their fascinating physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, three dimensionally (3D) interconnected carbon porous ... [more ▼]

Thanks to their fascinating physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, three dimensionally (3D) interconnected carbon porous frameworks have emerged as attractive materials for various electrochemical energy storage/conversion devices, including Li-ion batteries (LIBs), Li−S batteries, supercapacitors and fuel cells. In this context, a hierarchically structured macro- and mesoporous N-doped carbon with dispersed Fe2O3 nanoparticles (NDC@Fe2O3) is prepared by thermal treatment of a novel composite composed by PMMA particles decorated by graphene oxide (GO), PPy and iron salts. The NDC@Fe2O3 composite exhibited high surface area with a hierarchical pores structure. The combination of Fe2O3 nanoparticles with porous carbon to form hybrid anode has been an efficient way to maintain the electronic integrity of the whole electrode since the carbon acts as a buffer layer to accommodate the volume variation and to provide multidimensional electron transport pathways during the charge/discharge process. [less ▲]

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See detailPILs as a new active material for radical organic batteries
Aqil, Mohamed ULg; Ouhib, Farid ULg; Aqil, Abdelhafid ULg et al

Poster (2016, October 13)

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See detailNovel promising way to synthesize non-isocyanate polyurethanes (NIPUs) for innovative coating applications against corrosion protection of metal surfaces
Panchireddy, Satyannarayana ULg; Grignard, Bruno ULg; Thomassin, Jean-Michel ULg et al

Poster (2016, October 13)

Polyurethanes (PUs) are one of the most widely used polymeric materials with applications in automotive, as sealants, adhesives, decorative, aircraft topcoats, for coatings or as foams for thermal and/or ... [more ▼]

Polyurethanes (PUs) are one of the most widely used polymeric materials with applications in automotive, as sealants, adhesives, decorative, aircraft topcoats, for coatings or as foams for thermal and/or acoustic insulation. Industrially, PUs are produced by copolymerization between polyols and polyisocyanates. Because of the toxicity issues related to the use of isocyanates, there is a need to develop greener and safer route to produce such polymers. This study reports on the synthesis of new sustainable isocyanates-free PU (NIPU) coatings for aluminium anticorrosion. In a first step, bio- and CO2-sourced cyclic carbonates monomers were synthesized by coupling of epoxydized vegetable oils with CO2 using a new efficient bicomponent organocatalyst. In second step formulations including cyclic carbonates/amines/additives were optimized to produce highly adhesive cross-linked NIPU coatings that show good resistance against solvents and long-term barriers preventing the corrosion of the aluminiumsubstrate [less ▲]

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See detailSynthesis and characterization of non-isocyanate polyurethane (NIPU) hydrogels
Gennen, Sandro ULg; Grignard, Bruno ULg; Thomassin, Jean-Michel ULg et al

Poster (2016, October 13)

Due to its good biocompatibility, biodegradation and excellent mechanical properties, polyurethane (PU) is a material of choice for biomedical applications (gloves, tubing, artificial membranes…) and, as ... [more ▼]

Due to its good biocompatibility, biodegradation and excellent mechanical properties, polyurethane (PU) is a material of choice for biomedical applications (gloves, tubing, artificial membranes…) and, as hydrogels, it was used as wound dressing, soft contact lenses, drug delivery systems and scaffolds for tissue engineering. Classically, PU are synthesized by a step-growth polymerization between poly (di-)ols and poly (di-) isocyanates. Due to the toxicity of isocyanates, REACH regulations have changed and, today, there is a need to develop greener and safer route to produce isocyanate-free PUs. This contribution focus on the synthesis of NIPU hydrogels by copolymerizing a bifunctional CO2-sourced hydrophilic PEG bi-cyclic carbonate with diamines in presence of a cross- linker. The PEG bi-cyclic carbonates was prepared via a CO2/epoxide coupling reactions using a new efficient organocatalytic system based on the use of an ammonium salt (TBAI) in combination with a fluorinated alcohol. [less ▲]

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See detailAlkylcobalt as source of radicals for the controlled polymerization of less activated vinyl monomer
Demarteau, Jérémy ULg; Cordella, Daniela ULg; Kermagoret, Anthony et al

Poster (2016, October 13)

Detailed reference viewed: 15 (5 ULg)