Delphine Chan-Seng

French National Centre for Scientific Research | CNRS · Institut Charles Sadron

Aiming an identifying an interfacial agent for polyethylene (PE)/poly(ethylene-co-vinyl alcohol) (EVOH) blends that are the main components found in flexible food packaging, triallyl isocyanurate and a molecule bearing two (2,2,6,6-tetramethylpiperidin-1-yl)oxyl...

Thermoresponsive bilayer hydrogels have gained attention due to their fast response time and excellent recovery. A side-by-side capillary-based microfluidic device has been used to produce thermoresponsive Janus fibers by photopolymerization of monomer streams. These fibers had one of their parts consisting in a thermoresponsive polymer obtained fr...

The microfluidic production of Janus/Hecate polymer microfibers with well-defined interfaces from miscible phases is reported. The process offers the tunability of the width and composition of each part constituting the...

Background fiber diameter is one of the most important morphological parameters which drives the applications of microfibers. This creates a need for the development of processes capable of producing a large variety of microfibers with a given diameter. To this regards, microfluidic spinning has recently emerged as an outstanding and simple techniq...

The use of cationic polymers in gene therapy aims at improving the circulation, protection and delivery of nucleic acids. The modification of poly(L-lysine) (PLL), including the insertion of hydrophobic moieties, is an efficient strategy to enhance the transfection efficiency of this synthetic delivery system. PLL is usually modified through either...

Some cytokines can reengineer anti-tumor immunity to modify the tumor micro-environment. Interleukin-27 (IL-27) can partially reduce tumor growth in several animal models, including prostate cancer. We hypothesized that addition of IL-18, which can induce the proliferation of several immune effector cells through inducing IFNγ could synergize with...

Oligomers comprising four or sixteen phenylalanine residues with regularly intercalated aliphatic chains of different lengths prepared by solid-phase synthesis exhibit sufficient thermal stability to be used as interfacial agents and processed for the preparation of poly(propylene-co-ethylene)-based composite materials. The investigation of their a...

Efficient and safe delivery of anticancer drugs such as 5-fluorouracil (5-FU) is still a challenge in chemotherapy. The combination of polymers with a luminescent probe offers a promising venue to develop nanoobjects for theranostics. Herein, upconversion nanoparticles (UCNPs) decorated with polymers based on N-(2-hydroxypropyl) methacrylamide at t...

Hyperbranched poly(N-(2-hydroxypropyl) methacrylamide)s grafted on upconversion nanoparticles (UCNPs) were prepared by surface-initiated self-condensing vinyl RAFT copolymerization after modification of the surface of the UCNPs with a RAFT chain transfer agent. The propagation of the polymerization was strongly affected by termination and transfer...

Nanosized gel particles, so-called nanogels, have attracted substantial interest in different application fields, thanks to their controllable and three-dimensional physical structure, good mechanical properties and potential biocompatibility. Literature reports many technologies for their preparation and design, however a recurrent limitation rema...

We have examined the role of a novel targeted cytokine, interleukin-27 (IL-27), modified at the C-terminus with a dual targeting and therapeutic heptapeptide, in treating prostate cancer. IL-27 has shown promise in halting tumor growth and mediating tumor regression in several cancer models, including prostate cancer. We describe our findings on th...

Thermoresponsive polymers, undergoing a reversible chemical or physical change using temperature as stimulus, attract increasing interest in particular as adaptable biomaterials. Except for zwitterionic polymers, fully charged polymers require the presence of specific ions to exhibit an upper critical solution temperature (UCST) in water. Herein, w...

Hyperbranched polymers (HBPs) have found use in a wide range of applications, such as optical, electronic and magnetic materials, coatings, additives, supramolecular chemistry, and biomedicine. HBPs have gained attention for the development of drug delivery systems due to the presence of internal cavities in their three-dimensional globular structu...

Aiming at developing efficient interfacial agents for fiber-reinforced composite materials, macromolecules are designed to have different components able to stick to the fiber and be compatible with the polymer matrix, respectively. Herein, macromolecules are prepared by solid-phase synthesis considering phenylalanine residues to promote adsorption...

Sequence-defined peptide triazole nucleic acids (PTzNA) were synthesized via a solid-phase orthogonal "AB + CD" iterative strategy. In this approach, AB and CD building blocks containing carboxylic acid (A), azide (B), alkyne (C) and primary amine (D) functions are assembled together by successive copper-catalyzed azide-alkyne cycloaddition (CuAAC)...

Polymer-based gene delivery vehicles benefit from the presence of hydrophilic groups that mitigate the inherent toxicity of polycations and that provide tunable polymer-DNA binding strength and stable complexes (polyplexes). However, hydrophilic groups screen charge, and as such can reduce cell uptake and transfection efficiency. We report the effe...

Successful gene delivery to skeletal muscle is a desirable goal, not only for treating muscle diseases, but also for immunization, treatment of metabolic disorders, and/or delivering gene expression that can treat systemic conditions, such as bone metastatic cancer, for example. Although naked DNA uptake into skeletal muscle is possible, it is larg...

A simplified strategy for preparing non-natural information-containing polymers is reported. The concept relies on the successive ligation of oligomers that contain minimal sequence motifs. It was applied here to the synthesis of digitally-encoded poly(triazole amide)s, in which propyl and 2-methyl propyl motifs are used to code 0 and 1, respective...

Abstract This article describes two convenient methods for removing the ω-terminal bromine atom of well-defined soluble polymer supports prepared by atom transfer radical polymerization (ATRP). The targeted soluble supports are linear polystyrene chains that contain an acid-labile p-alkoxybenzyl ester linker (i.e. Wang linker) at their α-chain end....

Nature has demonstrated a high level of control of the primary structure of their macromolecules, control that chemists have attempted to reach through the development of different synthetic routes. Here a iterative strategy for the preparation of relatively long sequence-defined oligomers constituted of natural α-amino acids and synthetic blocks a...

Solid-phase synthesis was exploited for the preparation of oligomers constructed from natural and synthetic building blocks by combining the formation of amide bonds and copper-assisted alkyne?azide cycloaddition reactions extending the variety of oligomers with well-defined primary structures accessible through this technique and providing control...

The success of nonviral transfection using polymers hinges on efficient nuclear uptake of nucleic acid cargo and overcoming intra- and extracellular barriers. By incorporating PKKKRKV heptapeptide pendent groups as nuclear localization signals (NLS) on a polymer backbone, we demonstrate protein expression levels higher than those obtained from JetP...

A library of eight sequence-defined model oligomers, whose sequence is based on a (0,1) binary code, is prepared through chemoselective repeating cycles of amidification and copper-assisted alkyne-azide cycloaddition reactions from a non-modified Wang resin. This library is constructed from two AB (A = acid, B = alkyne) building blocks, i.e., 4-pen...

Front Cover: A possible strategy to encrypt information at the molecular level is the creation of a binary code using two co-monomers defined as 0 and 1. As a proof of principle, sequence-defined oligo(triazole amide)s are synthesized via a stepwise solid-phase iterative process. In this approach, a reactive spacer, namely 1-amino-11-azido-3,6,9-tr...

We have examined the role of a novel cytokine, interleukin-27 (IL-27), in mediating interactions between prostate cancer and bone. IL-27 is the most recently characterized member of the family of heterodimeric IL-12-related cytokines and has shown promise in halting tumor growth and mediating tumor regression in several cancer models, including pro...

The effect of mechanical constraints on the anti-polyelectrolyte behavior of zwitterionic polymers was studied systematically in this work via viscosity examination of uncross-linked polymer solutions, swelling of cross-linked polymer gels and swelling of elastomers compounded with these gels. Zwitterionic polymers, poly(sulfobetaine methacrylate)...

The present trend article analyzes recent progress in synthetic polymer chemistry. In particular, it emphasizes the importance of microstructural parameters such as stereoregularity and monomer sequences in polymer design allowing the preparation of highly complex ordered structures. This message is illustrated herein by examples from our laborator...

The automated sequence-controlled copolymerization of styrene and N-substituted maleimides allowed the production of unprecedented polymer microstructures (up to 65536 possible microstructural arrangements). Highly complex monomer sequence patterns were prepared using four N-substituted maleimides.

A series of styrenic monomers containing strong donor substituents (i.e., 4-methylstyrene, 4-acetoxystyrene, and 4-tert-butoxystyrene) were tested in sequence-controlled radical copolymerizations in the presence of acceptor comonomers (i.e., N-substituted maleimide). The copolymers were synthesized by nitroxide-mediated polymerization using the com...

A synthesizer is discussed which is equipped with various tools able to distribute solid and liq. reagents, perform reactions under inert gas upon heating, withdraw samples during the polymn., etc. permitting the adaptation of the polymn. traditionally performed by a chemist with std. chem. glassware to this robotic platform. [on SciFinder(R)]

Poly(L-lysine) (PLL) is a cationic polyelectrolyte of interest for many applications, including in therapeutic biology for DNA complexation and transfection. Several non-lysine based polycations have been shown to afford more efficient transfection in live cells than has been achieved with PLL. We find that reconfiguring polylysine into short oligo...

Ring-opening terpolymerization of L-lactide (LA), -caprolactone (CL), and glycolide (GA) was performed in the presence of tin (II) 2-ethylhexanoate at 170 degrees C. Random terpolyesters with weight-average molecular weight up to 130,000 g/mol were obtained. These terpolyesters, especially those with LA:CL:GA composition of 3:1:1, provided good coa...

Phosphorylcholine (PC)-substitution on aliphatic polyesters is accomplished by click chemistry with PC-substituted azides.

Living radical polymerizations of acrylate are known to be difficult to achieve using TEMPO as a mediator. The stable free radical polymerization (SFRP) of acrylate tends to stop at low monomer conversion due to the accumulation of TEMPO in the medium as a result of unavoidable bimolecular termination. Rather than solving this problem by destroying...

Living-radical polymerization of acrylates were performed under emulsion atom transfer radical polymerization (ATRP) conditions using latexes prepared by a nanoprecipitation technique previously employed and optimized for the polymerization of styrene. A macroinitiator of poly(n-butyl acrylate) prepared under bulk ATRP was dissolved in acetone and...

The radical polymerization of styrene and n-butyl acrylate is demonstrated to proceed under controlled conditions between 125 and 130 °C in the presence of either a 1,5-dimethyl-3-phenyl-6-oxoverdazyl radical or a 1,5-dimethyl-3-ethyl-6-oxoverdazyl radical producing polymers with polydispersity indices in the 1.2−1.3 range. While polymerizations in...

An efficient procedure for the oxidation of 1,1-diadamantylamine with m-chloroperbenzoic acid (m-CPBA) to the corresponding sterically hindered nitroxide in high yield (72%) is reported. The corresponding styrene-based alkoxyamine was synthesized by an atom transfer radical addition (ATRA) reaction. Because of the bulkiness of the adamantyl substit...

Attempted controlled polymerizations of styrene, conducted in the pre-sence of either 1,3,5 triphenyl-6-oxoverdazyl or 1,5-dimethyl-3-phenyl-6-oxoverdazyl radicals initiated with benzoyl peroxide or 1,10-azobis(cyclohexanecarbonitrile) were universally unsuccessful regardless of the reaction temperature and the initiator/ verdazyl molar ratio. No i...

Attempted controlled polymerizations of styrene, conducted in the presence of either 1,3,5-triphenyl-6-oxoverdazyl or 1,5-dimethyl-3-phenyl-6-oxoverdazyl radicals initiated with benzoyl peroxide or 1,1′-azobis(cyclohexanecarbonitrile) were universally unsuccessful regardless of the reaction temperature and the initiator/verdazyl molar ratio. No imp...

Living radical polymerizations of styrene were performed under emulsion atom transfer radical polymerization conditions with latexes prepared by a nanoprecipitation technique recently developed for the stable free-radical polymerization process. Latexes were prepared by the precipitation of a solution of low-molecular-weight polystyrene in acetone...

We present the synthesis of hyperbranched polymer-silica hybrid nanoparticles by self-condensing vinyl polymn. (SCVP) via atom transfer radical polymn. (ATRP) from silica surfaces. ATRP initiators were covalently linked to the surface of silica particles, followed by SCVP of an initiator-monomer (\"inimer\") which has both a polymerizable acrylic g...

We report on the synthesis of randomly branched (arborescent) poly(acrylic acid) (PAA) by self-condensing vinyl copolymn. (SCVCP) of an acrylic AB* inimer, 2-(2-bromopropionyloxy)ethyl acrylate (BPEA), with tert-Bu acrylate (tBuA) via atom transfer radical polymn. (ATRP), followed by hydrolysis of tert-Bu groups. Depending on the comonomer ratio, g...

We present the synthesis of hyperbranched polymer-silica hybrid nanoparticles by self-condensing vinyl polymn. (SCVP) via atom transfer radical polymn. (ATRP) from silica surfaces. ATRP initiators were covalently linked to the surface of silica particles, followed by SCVP of an initiator-monomer (\"inimer\") which has both a polymerizable acrylic g...