title: Thermoswitchable Janus Gold Nanoparticles with Stimuli-Responsive Hydrophilic Polymer Brushes.
abstract: Well-defined thermoswitchable Janus gold nanoparticles with stimuli-responsive hydrophilic polymer brushes were fabricated by combining ligand exchange reactions and the Langmuir technique. Stimuli-responsive polydi(ethylene glycol) methyl ether methacrylate was prepared by addition-fragmentation chain-transfer polymerization. The polymer brushes were then anchored onto the nanoparticle surface by interfacial ligand exchange reactions with hexanethiolate-protected gold nanoparticles, leading to the formation of a hydrophilic (polymer) hemisphere and a hydrophobic (hexanethiolate) one. The resulting Janus nanoparticles showed temperature-switchable wettability, hydrophobicity at high temperatures, and hydrophilicity at low temperatures, due to thermally induced conformational transition of the polymer ligands. The results further highlight the importance of interfacial engineering in the deliberate functionalization of nanoparticle materials.
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Niu
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.|State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology , Lanzhou 730050, P. R. China.
authors.forename: Fen
authors.initials: F
authors.lastname: Ran
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Limei
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Gabriella Jia-En
authors.initials: GJ
authors.lastname: Lu
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Peiguang
authors.initials: P
authors.lastname: Hu
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Deming
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Yi
authors.initials: Y
authors.lastname: Peng
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Mauricio D
authors.initials: MD
authors.lastname: Rojas-Andrade
authors.affiliation: Department of Chemistry and Biochemistry, University of California , 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Shaowei
authors.initials: S
authors.lastname: Chen