title: Chain conformation of a new class of PEG-based thermoresponsive polymer brushes grafted on silicon as determined by neutron reflectometry.
abstract: The thermoresponsive PEG-based copolymer poly[2-(2-methoxyethoxy)ethyl methacrylate-co-oligo(ethylene glycol) methacrylate) (P(MEO(2)MA-co-OEGMA)] was grafted onto a silicon wafer, and its chain conformation in aqueous solution was studied by neutron reflectometry. The effects of temperature and salt concentration on the polymer's conformation were evaluated. With increasing temperature, it was found that the polymer brushes underwent a transition from an extended state to a compressed state, and eventually a collapsed state above the lower critical solution temperature. The presence of salt significantly affected the well-extended brushes but had little effect on compressed and collapsed brushes. This PEG-based thermoresponsive surface exhibited good protein adsorption resistance. Interestingly, extended and collapsed brushes showed the same level of protein repulsion, something that was not expected.
authors.affiliation: Department of Chemical Engineering, McMaster University, Hamilton, Ontario, Canada, L8S 4L7.
authors.forename: Xiang
authors.initials: X
authors.lastname: Gao
authors.forename: Norbert
authors.initials: N
authors.lastname: Kucerka
authors.forename: Mu-Ping
authors.initials: MP
authors.lastname: Nieh
authors.forename: John
authors.initials: J
authors.lastname: Katsaras
authors.forename: Shiping
authors.initials: S
authors.lastname: Zhu
authors.forename: John L
authors.initials: JL
authors.lastname: Brash
authors.forename: Heather
authors.initials: H
authors.lastname: Sheardown
mesh_terms: D000327:Adsorption; D002627:Chemistry, Physical / Q000379:methods; D006801:Humans; D008956:Models, Chemical; D008968:Molecular Conformation; D009502:Neutrons; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D011108:Polymers; D011506:Proteins; D014867:Water; D011092:Polyethylene Glycols; D012825:Silicon