Guillaume Delaittre | Karlsruhe Institute of Technology (KIT) (original) (raw)

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Papers by Guillaume Delaittre

Research paper thumbnail of Cascade Reactions in an All-Enzyme Nanoreactor

Chemistry-a European Journal, 2009

ABSTRACT Good things come in small packages! Giant amphiphiles, consisting of a polymeric hydroph... more ABSTRACT Good things come in small packages! Giant amphiphiles, consisting of a polymeric hydrophobic tail and a horseradish peroxidase head, were simultaneously synthesized and self-assembled into vesicles. During the self-assembly process, glucose oxidase was encapsulated to create enzymatic cascade nanoreactors (see picture; ABTS= 2,2′-azido-bis(3-ethylbenzthiazoline-6-sulfonic acid)).

Research paper thumbnail of Solution scattering studies on a virus capsid protein as a building block for nanoscale assemblies

Self-assembled protein cages are versatile building blocks in the construction of biomolecular na... more Self-assembled protein cages are versatile building blocks in the construction of biomolecular nanostructures. Because of the defined assembly behaviour the cowpea chlorotic mottle virus (CCMV) protein is often used for such applications. Here we report a ...

Research paper thumbnail of Amine-reactive pegylated nanoparticles for potential bioconjugation

Macromolecular Rapid Communications, 2011

Research paper thumbnail of Nitroxide-Mediated Living/Controlled Radical Polymerization ofN,N-Diethylacrylamide

Macromolecules, 2011

ABSTRACT Well-defined poly(N,N-diethylacrylamide)s were synthesized for the first time by nitroxi... more ABSTRACT Well-defined poly(N,N-diethylacrylamide)s were synthesized for the first time by nitroxide-mediated polymerization. The polymerizations were first performed in toluene solution, using BlocBuilder, a tertiary alkoxyamine based on the nitroxide SG1 (N-tert-butyl-N-[1-diethylphosphono-(2,2-dimethylpropyl)] nitroxide), as an initiator without initial free nitroxide. High monomer conversions were reached, up to completion and the number-average molar masses increased linearly with conversion. However the polydispersity indices (PDI) remained quite high, despite a constant diminution with increasing conversion until a value of 1.9 at high conversion. This could be corrected by the addition of free SG1 at the onset of the reaction, leading to PDI of 1.2 at 93% conversion in the best case. Various alkoxyamine concentrations were used to target different molar masses. The presence of SG1 functionality at the ω-end of the polymer chains was evidenced by size-exclusion chromatography coupled to electospray ionization mass spectrometry (SEC/ESI−MS) and the living character of the latter was proved by efficient chain extension with styrene or N,N-dimethylacrylamide.

Research paper thumbnail of Formation of polymer vesicles by simultaneous chain growth and self-assembly of amphiphilic block copolymers

Chemical Communications, 2009

Polymerization-induced formation of amphiphilic diblock copolymer vesicles is performed in water ... more Polymerization-induced formation of amphiphilic diblock copolymer vesicles is performed in water at high concentrations by a single-step nitroxide-mediated controlled free-radical emulsion polymerization of 4-vinylpyridine, initiated by a water-soluble poly(sodium acrylate) macroalkoxyamine at alkaline pH.

Research paper thumbnail of Preparation of Hybrid Latex Particles and Core–Shell Particles Through the Use of Controlled Radical Polymerization Techniques in Aqueous Media

The synthesis of hybrid and core–shell nanoparticles using controlled/ living radical polymerizat... more The synthesis of hybrid and core–shell nanoparticles using controlled/ living radical polymerization in aqueous dispersed systems is reviewed. The processes involve emulsion, miniemulsion, and dispersion polymerizations as well as grafting techniques, with the aim of producing submicrometric latex particles with well-defined morphologies that might not be accessible via classical radical polymerization. Those morphologies include organic/inorganic hybrids, nanostructured particles, (nano)capsules, and particles with a hydrophobic core and hydrophilic shell.

Research paper thumbnail of Kinetics of in-Situ Formation of Poly(acrylic acid)-b-polystyrene Amphiphilic Block Copolymers via Nitroxide-Mediated Controlled Free-Radical Emulsion Polymerization. Discussion on the Effect of Compartmentalization on the Polymerization Rate

Macromolecules, 2008

ABSTRACT The kinetics of surfactant-free, ab initio, batch emulsion polymerization of styrene med... more ABSTRACT The kinetics of surfactant-free, ab initio, batch emulsion polymerization of styrene mediated by the nitroxide SG1 ((N-tert-butyl-N-1-diethylphosphono-(2,2-dimethylpropyl) nitroxide) in the presence of a poly(sodium acrylate) macroalkoxyamine playing the role of both the initiator and the stabilizer were studied, and the influence of the compartmentalization of the propagating radicals on the monomer conversion rate was discussed. It was pointed out that the local monomer concentration within very small particles has to be considered with great care. The results showed that free nitroxide was not compartmentalized and that the kinetics were not particularly affected by particle size, even for very small particles below 66 nm in diameter.

Research paper thumbnail of Surfactant-free synthesis of amphiphilic diblock copolymer nanoparticles via nitroxide-mediated emulsion polymerization

Chemical Communications, 2005

Amphiphilic hairy nanoparticles are prepared in a one step, batch, heterogeneous polymerization o... more Amphiphilic hairy nanoparticles are prepared in a one step, batch, heterogeneous polymerization of styrene or n-butyl acrylate, using a water-soluble poly(sodium acrylate) alkoxyamine macroinitiator based on the SG1 nitroxide.

Research paper thumbnail of Nitroxide-Mediated Controlled Free-Radical Emulsion Polymerization with a novel SG1-based Water-soluble Alkoxyamine

Research paper thumbnail of Nitroxide-Mediated Aqueous Dispersion Polymerization: From Water-Soluble Macroalkoxyamine to Thermosensitive Nanogels

Macromolecular Rapid Communications, 2007

Research paper thumbnail of Aqueous suspension of amphiphilic diblock copolymer nanoparticles prepared in situ from a water-soluble poly(sodium acrylate) alkoxyamine macroinitiator

Soft Matter, 2006

The simple, one step synthesis of aqueous suspensions of amphiphilic nanoparticles is presented. ... more The simple, one step synthesis of aqueous suspensions of amphiphilic nanoparticles is presented. Those particles are prepared in the batch heterophase polymerization of styrene or n-butyl acrylate, using a water-soluble poly(sodium acrylate) alkoxyamine macroinitiator. The nitroxidemediated controlled growth of the hydrophobic block leads to the formation of poly(sodium acrylate)-b-polystyrene or poly(sodium acrylate)-b-poly(n-butyl acrylate) amphiphilic diblock copolymers, able to self-assemble in water simultaneously to the growth step. When the diblock copolymers become strongly asymmetrical, with a short poly(sodium acrylate) block and a long hydrophobic one, the formed hairy nanoparticles are analogous to amphiphilic diblock copolymer crew-cut micelles.

Research paper thumbnail of Cascade Reactions in an All-Enzyme Nanoreactor

Chemistry-a European Journal, 2009

ABSTRACT Good things come in small packages! Giant amphiphiles, consisting of a polymeric hydroph... more ABSTRACT Good things come in small packages! Giant amphiphiles, consisting of a polymeric hydrophobic tail and a horseradish peroxidase head, were simultaneously synthesized and self-assembled into vesicles. During the self-assembly process, glucose oxidase was encapsulated to create enzymatic cascade nanoreactors (see picture; ABTS= 2,2′-azido-bis(3-ethylbenzthiazoline-6-sulfonic acid)).

Research paper thumbnail of Solution scattering studies on a virus capsid protein as a building block for nanoscale assemblies

Self-assembled protein cages are versatile building blocks in the construction of biomolecular na... more Self-assembled protein cages are versatile building blocks in the construction of biomolecular nanostructures. Because of the defined assembly behaviour the cowpea chlorotic mottle virus (CCMV) protein is often used for such applications. Here we report a ...

Research paper thumbnail of Amine-reactive pegylated nanoparticles for potential bioconjugation

Macromolecular Rapid Communications, 2011

Research paper thumbnail of Nitroxide-Mediated Living/Controlled Radical Polymerization ofN,N-Diethylacrylamide

Macromolecules, 2011

ABSTRACT Well-defined poly(N,N-diethylacrylamide)s were synthesized for the first time by nitroxi... more ABSTRACT Well-defined poly(N,N-diethylacrylamide)s were synthesized for the first time by nitroxide-mediated polymerization. The polymerizations were first performed in toluene solution, using BlocBuilder, a tertiary alkoxyamine based on the nitroxide SG1 (N-tert-butyl-N-[1-diethylphosphono-(2,2-dimethylpropyl)] nitroxide), as an initiator without initial free nitroxide. High monomer conversions were reached, up to completion and the number-average molar masses increased linearly with conversion. However the polydispersity indices (PDI) remained quite high, despite a constant diminution with increasing conversion until a value of 1.9 at high conversion. This could be corrected by the addition of free SG1 at the onset of the reaction, leading to PDI of 1.2 at 93% conversion in the best case. Various alkoxyamine concentrations were used to target different molar masses. The presence of SG1 functionality at the ω-end of the polymer chains was evidenced by size-exclusion chromatography coupled to electospray ionization mass spectrometry (SEC/ESI−MS) and the living character of the latter was proved by efficient chain extension with styrene or N,N-dimethylacrylamide.

Research paper thumbnail of Formation of polymer vesicles by simultaneous chain growth and self-assembly of amphiphilic block copolymers

Chemical Communications, 2009

Polymerization-induced formation of amphiphilic diblock copolymer vesicles is performed in water ... more Polymerization-induced formation of amphiphilic diblock copolymer vesicles is performed in water at high concentrations by a single-step nitroxide-mediated controlled free-radical emulsion polymerization of 4-vinylpyridine, initiated by a water-soluble poly(sodium acrylate) macroalkoxyamine at alkaline pH.

Research paper thumbnail of Preparation of Hybrid Latex Particles and Core–Shell Particles Through the Use of Controlled Radical Polymerization Techniques in Aqueous Media

The synthesis of hybrid and core–shell nanoparticles using controlled/ living radical polymerizat... more The synthesis of hybrid and core–shell nanoparticles using controlled/ living radical polymerization in aqueous dispersed systems is reviewed. The processes involve emulsion, miniemulsion, and dispersion polymerizations as well as grafting techniques, with the aim of producing submicrometric latex particles with well-defined morphologies that might not be accessible via classical radical polymerization. Those morphologies include organic/inorganic hybrids, nanostructured particles, (nano)capsules, and particles with a hydrophobic core and hydrophilic shell.

Research paper thumbnail of Kinetics of in-Situ Formation of Poly(acrylic acid)-b-polystyrene Amphiphilic Block Copolymers via Nitroxide-Mediated Controlled Free-Radical Emulsion Polymerization. Discussion on the Effect of Compartmentalization on the Polymerization Rate

Macromolecules, 2008

ABSTRACT The kinetics of surfactant-free, ab initio, batch emulsion polymerization of styrene med... more ABSTRACT The kinetics of surfactant-free, ab initio, batch emulsion polymerization of styrene mediated by the nitroxide SG1 ((N-tert-butyl-N-1-diethylphosphono-(2,2-dimethylpropyl) nitroxide) in the presence of a poly(sodium acrylate) macroalkoxyamine playing the role of both the initiator and the stabilizer were studied, and the influence of the compartmentalization of the propagating radicals on the monomer conversion rate was discussed. It was pointed out that the local monomer concentration within very small particles has to be considered with great care. The results showed that free nitroxide was not compartmentalized and that the kinetics were not particularly affected by particle size, even for very small particles below 66 nm in diameter.

Research paper thumbnail of Surfactant-free synthesis of amphiphilic diblock copolymer nanoparticles via nitroxide-mediated emulsion polymerization

Chemical Communications, 2005

Amphiphilic hairy nanoparticles are prepared in a one step, batch, heterogeneous polymerization o... more Amphiphilic hairy nanoparticles are prepared in a one step, batch, heterogeneous polymerization of styrene or n-butyl acrylate, using a water-soluble poly(sodium acrylate) alkoxyamine macroinitiator based on the SG1 nitroxide.

Research paper thumbnail of Nitroxide-Mediated Controlled Free-Radical Emulsion Polymerization with a novel SG1-based Water-soluble Alkoxyamine

Research paper thumbnail of Nitroxide-Mediated Aqueous Dispersion Polymerization: From Water-Soluble Macroalkoxyamine to Thermosensitive Nanogels

Macromolecular Rapid Communications, 2007

Research paper thumbnail of Aqueous suspension of amphiphilic diblock copolymer nanoparticles prepared in situ from a water-soluble poly(sodium acrylate) alkoxyamine macroinitiator

Soft Matter, 2006

The simple, one step synthesis of aqueous suspensions of amphiphilic nanoparticles is presented. ... more The simple, one step synthesis of aqueous suspensions of amphiphilic nanoparticles is presented. Those particles are prepared in the batch heterophase polymerization of styrene or n-butyl acrylate, using a water-soluble poly(sodium acrylate) alkoxyamine macroinitiator. The nitroxidemediated controlled growth of the hydrophobic block leads to the formation of poly(sodium acrylate)-b-polystyrene or poly(sodium acrylate)-b-poly(n-butyl acrylate) amphiphilic diblock copolymers, able to self-assemble in water simultaneously to the growth step. When the diblock copolymers become strongly asymmetrical, with a short poly(sodium acrylate) block and a long hydrophobic one, the formed hairy nanoparticles are analogous to amphiphilic diblock copolymer crew-cut micelles.