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International audienceThe nitroxide-mediated copolymerization of poly(ethylene glycol) methyl ether methacrylate (MePEGMA) with a small amount of acrylonitrile using an SG1-based alkoxyamine initiator was shown to be a very simple and efficient technique to synthesize graft copolymers with poly(ethylene glycol) side chains. The copolymerizations were carried out in ethanol/water solutions as environmentally friendly media. Following our observation that the rate increased with the proportion of water, a polymerization temperature as low as 71 °C could be used for a water content of 75%, which conferred great flexibility to the process. The so-formed copolymers were living, with high crossover efficiency toward block copolymers. Importantly, following a cytotoxicity study over three different cell lines that represent important mammalian cell types, these polymers were shown to be noncytotoxic even at very high doses without any other purification step than a simple precipitation. These comb-shaped PEG-based polymers may represent an ideal platform for the synthesis of PEGylating moieties for proteins and nanoparticles intended to be used in the biomedical field

International audienceWell-defined fluorescent, alpha-functional polymethacrylates with PEG side chains were readily designed by nitroxide-mediated polymerization (NMP) from N-hydroxysuccinimidyl (NHS) ester-containing alkoxyamines based on the nitroxide SG1. These polymers were obtained without any purification beyond a simple precipitation. They exhibited tunable reactivities towards nucleophiles depending on the nature of the alkoxyamine used. Copolymers derived from the commercially available SG1-based alkoxyamine led to quantitative coupling with small molecules and a neuroprotective peptide whereas partial conjugation was obtained with lysozyme, used here as a model protein. Complete conjugation to the latter was obtained from similar copolymers exhibiting a less sterically hindered NHS extremity, via appropriate alkoxyamine structure, which represents the very first example of peptide/protein PEGylation with functional polymers derived from NMP