title: Protein adsorption on oligo(ethylene glycol)-terminated alkanethiolate self-assembled monolayers: The molecular basis for nonfouling behavior.
abstract: A study of protein resistance of oligo(ethylene glycol) (OEG), HS(CH2)11(OCH2CH2)nOH (n = 2, 4, and 6), self-assembled monolayers (SAMs) on Au(111) surfaces is presented here. Hydroxyl-terminated OEG-SAMs are chosen to avoid the hydrophobic effect observed with methyl-terminated OEG-SAMs, particularly at high packing densities. The structure of the OEG-SAM surfaces is controlled by adjusting the assembly solvent. These SAMs were characterized by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Protein adsorption on these surfaces was investigated by surface plasmon resonance (SPR). OEG-SAMs assembled from mixed ethanol and water solutions show higher packing density on gold than those from pure ethanol solution. For EG2OH- and EG4OH-SAMs, proteins (i.e., fibrinogen and lysozyme) adsorb more on the densely packed SAMs prepared from mixed ethanol and water solutions, while EG6OH-SAMs generally resist protein adsorption regardless of the assembly solvent used.
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, Washington 98105, USA.
authors.forename: Lingyan
authors.initials: L
authors.lastname: Li
authors.forename: Shengfu
authors.initials: S
authors.lastname: Chen
authors.forename: Jie
authors.initials: J
authors.lastname: Zheng
authors.forename: Buddy D
authors.initials: BD
authors.lastname: Ratner
authors.forename: Shaoyi
authors.initials: S
authors.lastname: Jiang
mesh_terms: D000327:Adsorption; D000473:Alkanes / Q000737:chemistry*; D000818:Animals; D001703:Biophysics / Q000379:methods; D002417:Cattle; D002627:Chemistry, Physical / Q000379:methods; D000431:Ethanol / Q000737:chemistry; D005026:Ethylene Glycols / Q000737:chemistry*; D005340:Fibrinogen / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D009113:Muramidase / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000473:Alkanes; D005026:Ethylene Glycols; D011506:Proteins; D012997:Solvents; D013438:Sulfhydryl Compounds; D000431:Ethanol; D006046:Gold; D005340:Fibrinogen; D009113:Muramidase