title: Temperature and pH dual-responsive coatings of oligoperoxide-graft-poly(N-isopropylacrylamide): wettability, morphology, and protein adsorption.
abstract: Poly(N-isopropylacrylamide) (PNIPAM) coatings attached to glass with novel approach involving polymerization from oligoperoxide grafted to surface with (3-aminopropyl)triethoxysilane exhibit not only temperature- but also pH-dependence of wettability and protein adsorption. Wettability and composition of coatings, fabricated with different polymerization times, were determined using contact angle measurements and Time Of Flight-Secondary Ion Mass Spectrometry (TOF-SIMS), respectively. Thermal response of wettability, measured between 20 and 40°C, was prominent at pH 9 and 7 and diminished or absent at pH 5 and 3. This indicates a transition between hydrated loose coils and hydrophobic collapsed chains that is blocked at low pH. Higher surface roughness and dramatically increased adsorption of model protein (lentil lectin labeled with fluorescein isothiocyanate) were observed with AFM and fluorescence microscopy to occur in hydrophobic phases (at pH 3, for pH varied at constant temperature of 22°C and at ∼33°C, for temperature varied at constant pH 9). Protein adsorption response to pH was confirmed by TOF-SIMS and Principal Component Analysis.
authors.affiliation: Lvivska Polytechnika National University, S. Bandery 12, 79013 Lviv, Ukraine. yrstecushun@ukr.net
authors.forename: Yurij
authors.initials: Y
authors.lastname: Stetsyshyn
authors.forename: Joanna
authors.initials: J
authors.lastname: Zemla
authors.forename: Oksana
authors.initials: O
authors.lastname: Zolobko
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Fornal
authors.forename: Andrzej
authors.initials: A
authors.lastname: Budkowski
authors.forename: Andrij
authors.initials: A
authors.lastname: Kostruba
authors.forename: Volodymyr
authors.initials: V
authors.lastname: Donchak
authors.forename: Kristina
authors.initials: K
authors.lastname: Harhay
authors.forename: Kamil
authors.initials: K
authors.lastname: Awsiuk
authors.forename: Jakub
authors.initials: J
authors.lastname: Rysz
authors.forename: Andrzej
authors.initials: A
authors.lastname: Bernasik
authors.forename: Stanislav
authors.initials: S
authors.lastname: Voronov
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D000180:Acrylic Resins; D000327:Adsorption; D005898:Glass / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D037102:Lectins / Q000737:chemistry*; D027806:Lens Plant / Q000737:chemistry*; D010545:Peroxides / Q000737:chemistry; D010940:Plant Proteins / Q000737:chemistry*; D058105:Polymerization; D011108:Polymers / Q000737:chemistry*; D013696:Temperature; D017155:Wettability
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D037102:Lectins; D010545:Peroxides; D010940:Plant Proteins; D011108:Polymers; C052970:poly-N-isopropylacrylamide