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Skin ulcers are a serious threat to public health system, and, although wound healing is a natural process, a proper dressing can improve the healing process. In this work, platelet rich plasma (PRP) coated polycaprolactone (PCL) wound dressings have been designed by means of electrospinning. PCL is a biocompatible and biodegradable synthetic polymer. PRP, in turn, offers growth factors to the dressing, which are significant in the healing. To enable an effective addition of PRP, functionalization of PCL fibre meshes has been carried out by immersing them in alkaline dissolution of different concentrations. In this way, a novel wound dressing that aids in the regeneration of damaged skin layers has been developed., Larruazal-ultzerak osasun publikoarentzat mehatxu larriak dira, eta zaurien orbaintzea prozesu naturala bada ere, zauri-jantzi egoki batek prozesuan lagundu dezake. Lan honetan, elektrospinning teknika bitartez, polikaprolaktonazko (PCL) zauri-jantziak diseinatu dira, zeinei plaketan aberatsa den plasma (PRP) estaldura gehitu zaie. PCL biobateragarria eta biodegradagarria den polimero sintetikoa da. PRPak aldiz, lesioa sendatzeko oso garrantzitsuak diren hazkunde-faktoreak eskaintzen dizkio zauri-jantziari. PRParen adizio eraginkorra ahalbidetzeko, PCLezko zuntz-sareen funtzionalizazioa burutu da hau kontzentrazio desberdineko disoluzio alkalinoetan murgilduz. Horrela, kaltetutako azalgeruzen birsortzea eragingo duen zauri-jantzia garatu da.

We report for the first time the synthesis of unimolecular polystyrene-based nanoparticles (PS-NPs) under normal air atmosphere by direct carbon-carbon “click” chemistry (i.e., “self-click” chemistry). First, statistical poly(styrene-co-4-vinylbenzyl chloride) copolymers synthesized by RAFT polymerization were decorated in a facile manner with alkyne groups by reaction with potassium propiolate, providing well-defined nanoparticle precursors (PS-Prec). Next, individual PS-Prec chains were collapsed irreversibly to unimolecular nanoparticles of ca. 12 nm in size by intrachain Cu(II)-catalyzed alkyne dimerization under high-dilution conditions, as revealed by SEC, H1-NMR, DLS and TEM measurements. Based on predictions from a recent compressible thermodynamic model, the resulting nanoparticles could be promising materials for the development of homogeneous, miscible PS-NPs / polycarbonate all-polymer nanocomposites

Protection of acetylenic monomers is a common practice to avoid parasitic side reactions during polymerization. Herein, we report that redox-initiated RAFT polymerization allows the direct, room temperature synthesis of a variety of single-chain nanoparticle precursors (displaying narrow molecular weight dispersity, M̄ wM̄ n = 1.12 -1.37 up to M̄ w = 100 kDa) containing well-defined amounts of naked, unprotected acetylenic functional groups available for rapid and quantitative intrachain cross-linking via metal-catalyzed carbon-carbon coupling (i.e., C-C click chemistry). To illustrate the useful self-clickable character of the new unprotected acetylenic precursors, single-chain nanoparticles have been prepared for the first time in a facile and highly efficient manner by copper-catalyzed alkyne homocoupling (i.e., Glaser-Hay coupling) at room temperature under normal air atmosphere.

Excellent dispersion of functionalized graphene (FG) sheets in polystyrene was achieved relying on the reaction of “living” poly(glycidyl phenyl ether) chains onto graphene sheets. The physical aging of polystyrene was substantially accelerated by the presence of FG sheets at low filler content, retaining film transparency and increasing the electrical conductivity.

"Click" chemistry has become an efficient avenue to unimolecular polymeric nanoparticles through the self-crosslinking of individual polymer chains containing appropriate functional groups. Herein we report the synthesis of ultra-small (7 nm in size) polymethyl methacrylate (PMMA) nanoparticles (NPs) by the "metal-free" cross-linking of PMMA-precursor chains prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization containing beta-ketoester functional groups. Intramolecular collapse was performed by the one-pot reaction of beta-ketoester moieties with alkyl diamines in tetrahydrofurane at r.t. (i.e., by enamine formation). The collapsing process was followed by size exclusion chromatography and by nuclear magnetic resonance spectroscopy. The size of the resulting PMMA-NPs was determined by dynamic light scattering. Enamine "click" chemistry increases the synthetic toolbox for the efficient synthesis of metal-free, ultra-small polymeric NPs.

“Click” chemistry has become an efficient avenue to unimolecular polymeric nanoparticles through the self-crosslinking of individual polymer chains containing appropriate functional groups. Herein we report the synthesis of ultra-small (7 nm in size) polymethyl methacrylate (PMMA) nanoparticles (NPs) by the “metal-free” cross-linking of PMMA-precursor chains prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization containing b-ketoester functional groups. Intramolecular collapse was performed by the one-pot reaction of b-ketoester moieties with alkyl diamines in tetrahydrofurane at r.t. (i.e., by enamine formation). The collapsing process was followed by size exclusion chromatography and by nuclear magnetic resonance spectroscopy. The size of the resulting PMMA-NPs was determined by dynamic light scattering. Enamine “click” chemistry increases the synthetic toolbox for the efficient synthesis of metal-free, ultra-small polymeric NPs.

“Click” chemistry has become an efficient avenue to unimolecular polymeric nanoparticles through the self-crosslinking of individual polymer chains containing appropriate functional groups. Herein we report the synthesis of ultra-small (7 nm in size) polymethyl methacrylate (PMMA) nanoparticles (NPs) by the “metal-free” cross-linking of PMMA-precursor chains prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization containing b-ketoester functional groups. Intramolecular collapse was performed by the one-pot reaction of b-ketoester moieties with alkyl diamines in tetrahydrofurane at r.t. (i.e., by enamine formation). The collapsing process was followed by size exclusion chromatography and by nuclear magnetic resonance spectroscopy. The size of the resulting PMMA-NPs was determined by dynamic light scattering. Enamine “click” chemistry increases the synthetic toolbox for the efficient synthesis of metal-free, ultra-small polymeric NPs.