title: Temperature-responsive self-assembled monolayers of oligo(ethylene glycol): control of biomolecular recognition.
abstract: Self-assembled monolayers (SAMs) of oligo(ethylene glycol) (OEG)-tethered molecules on gold are important for various biorelevant applications ranging from biomaterials to bioanalytical devices, where surface resistance to nonspecific protein adsorption is needed. Incorporation of a stimuli-responsive character to the OEG SAMs enables the creation of nonfouling surfaces with switchable functionality. Here we present an OEG-derived structure that is highly responsive to temperature changes in the vicinity of the physiological temperature, 37 degrees C. The temperature-responsive solution behavior of this new compound was demonstrated by UV-vis and nuclear magnetic resonance spectroscopy. Its chemisorption onto gold(111), and the retention of responsive behavior after chemisorption have been demonstrated by surface plasmon resonance (SPR), X-ray photoelectron spectroscopy (XPS), and atomic force and scanning tunneling microscopy. The OEG-derived SAMs have been shown to reversibly switch the wettability of the surface, as determined by contact angle measurements. More importantly, SPR and AFM studies showed that the OEG SAMs can be utilized to control the affinity binding of streptavidin to the biotin-tethered surface in a temperature-dependent manner while still offering the nonspecific protein-resistance to the surface.
authors.affiliation: Institute for Nanoscale Technology, University of Technology, Sydney (UTS), Sydney 2007, Australia. hadi.zareie@uts.edu.au
authors.forename: Hadi M
authors.initials: HM
authors.lastname: Zareie
authors.forename: Cyrille
authors.initials: C
authors.lastname: Boyer
authors.forename: Volga
authors.initials: V
authors.lastname: Bulmus
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Nateghi
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Davis
mesh_terms: D001704:Biopolymers / Q000032:analysis; D015374:Biosensing Techniques / Q000379:methods*; D001710:Biotin / Q000737:chemistry; D003460:Crystallization / Q000379:methods*; D019855:Ethylene Glycol / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D007118:Immunoassay / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods; D010316:Particle Size; D019809:Streptavidin / Q000032:analysis / Q000737:chemistry; D013499:Surface Properties; D013817:Thermography / Q000379:methods*
chemical_list: D001704:Biopolymers; D046911:Macromolecular Substances; D001710:Biotin; D006046:Gold; D019809:Streptavidin; D019855:Ethylene Glycol