title: Poly(ε-caprolactone)-block-polysarcosine by Ring-Opening Polymerization of Sarcosine N-Thiocarboxyanhydride: Synthesis and Thermoresponsive Self-Assembly.
abstract: Biocompatible amphiphilic block copolymers composed of polysarcosine (PSar) and poly(ε-caprolactone) (PCL) were synthesized using ring-opening polymerization of sarcosine N-thiocarboxyanhydride initiated by oxyamine-ended PCL and characterized by NMR, SEC, and DSC. Self-assembling of two triblock copolymers PSar8-b-PCL28-b-PSar8 (CS7) and PSar16-b-PCL40-b-PSar16 (CS10) in dilute solution was studied in detail toward polymersome formation using thin-film hydration and nanoprecipitation techniques. A few giant vesicles were obtained by thin-film hydration from both copolymers and visualized by confocal laser scanning microscope. Unilamellar sheets and nanofibers (with 8-10 nm thickness or diameter) were obtained by nanoprecipitation at room temperature and observed by Cryo-TEM. These lamellae and fibrous structures were transformed into worm-like cylinders and spheres (D∼30-100 nm) after heating to 65 °C (>Tm,PCL). Heating CS10 suspensions to 90 °C led eventually to multilamellar polymersomes (D∼100-500 nm). Mechanism II, where micelles expand to vesicles through water diffusion and hydrophilic core forming, was proposed for polymersome formation. A cell viability test confirmed the self-assemblies were not cytotoxic.
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University , 310027 Hangzhou, China.|Institut Curie - CNRS - Université Pierre and Marie Curie , Laboratoire Physico-Chimie Curie, UMR168, 26 Rue d'Ulm, 75248 Paris, France.
authors.forename: Yangwei
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Institut Curie - CNRS - Université Pierre and Marie Curie , Laboratoire Physico-Chimie Curie, UMR168, 26 Rue d'Ulm, 75248 Paris, France.
authors.forename: Tao
authors.initials: T
authors.lastname: Zou
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University , 310027 Hangzhou, China.
authors.forename: Xinfeng
authors.initials: X
authors.lastname: Tao
authors.affiliation: Institut Curie - CNRS - Université Pierre and Marie Curie , Laboratoire Physico-Chimie Curie, UMR168, 26 Rue d'Ulm, 75248 Paris, France.|Institut de Recherche de Chimie Paris, UMR8247, CNRS - Chimie ParisTech (ENSCP) , 11 rue Pierre et Marie Curie, 75231 Paris, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Semetey
authors.affiliation: Institut Curie, INSERM U1196, 91405 Orsay cedex, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Trepout
authors.affiliation: Institut Curie, INSERM U1196, 91405 Orsay cedex, France.
authors.forename: Sergio
authors.initials: S
authors.lastname: Marco
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University , 310027 Hangzhou, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Ling
authors.affiliation: Institut Curie - CNRS - Université Pierre and Marie Curie , Laboratoire Physico-Chimie Curie, UMR168, 26 Rue d'Ulm, 75248 Paris, France.|Institut de Recherche de Chimie Paris, UMR8247, CNRS - Chimie ParisTech (ENSCP) , 11 rue Pierre et Marie Curie, 75231 Paris, France.
authors.forename: Min-Hui
authors.initials: MH
authors.lastname: Li
mesh_terms: D002152:Calorimetry, Differential Scanning; D020285:Cryoelectron Microscopy / Q000379:methods*; D010455:Peptides / Q000737:chemistry*; D011091:Polyesters / Q000737:chemistry*; D058105:Polymerization; D012521:Sarcosine / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D010455:Peptides; D011091:Polyesters; C016240:polycaprolactone; C015475:polysarcosine; D012521:Sarcosine