title: Mixed poly (ethylene glycol) and oligo (ethylene glycol) layers on gold as nonfouling surfaces created by backfilling.
abstract: Backfilling a self-assembled monolayer (SAM) of long poly (ethylene glycol) (PEG) with short PEG is a well-known strategy to improve its potential to resist fouling. Here it is shown, using x-ray photoelectron spectroscopy, contact angle, and atomic force microscopy, that backfilling PEG thiol with oligo (ethylene glycol) (OEG) terminated alkane thiol molecules results in underbrush formation. The authors also confirm the absence of phase separated arrangement, which is commonly observed with backfilling experiments involving SAMs of short chain alkane thiol with long chain alkane thiol. Furthermore, it was found that OEG addition caused less PEG desorption when compared to alkane thiol. The ability of surface to resist fouling was tested through serum adsorption and bacterial adhesion studies. The authors demonstrate that the mixed monolayer with PEG and OEG is better than PEG at resisting protein adsorption and bacterial adhesion, and conclude that backfilling PEG with OEG resulting in the underbrush formation enhances the ability of PEG to resist fouling.
authors.affiliation: The Interdisciplinary Nanoscience Centre, Aarhus University, Denmark.
authors.forename: Arcot R
authors.initials: AR
authors.lastname: Lokanathan
authors.forename: Shuai
authors.initials: S
authors.lastname: Zhang
authors.forename: Viduthalai R
authors.initials: VR
authors.lastname: Regina
authors.forename: Martin A
authors.initials: MA
authors.lastname: Cole
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Ogaki
authors.forename: Mingdong
authors.initials: M
authors.lastname: Dong
authors.forename: Flemming
authors.initials: F
authors.lastname: Besenbacher
authors.forename: Rikke L
authors.initials: RL
authors.lastname: Meyer
authors.forename: Peter
authors.initials: P
authors.lastname: Kingshott
mesh_terms: D001422:Bacterial Adhesion / Q000187:drug effects; D057219:Biofouling / Q000517:prevention & control*; D055119:Elastic Modulus / Q000187:drug effects; D006046:Gold / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D056951:Photoelectron Spectroscopy; D011092:Polyethylene Glycols / Q000737:chemistry / Q000494:pharmacology*; D058525:Quartz Crystal Microbalance Techniques; D013211:Staphylococcus aureus / Q000187:drug effects / Q000502:physiology; D013500:Surface Tension / Q000187:drug effects
chemical_list: D011092:Polyethylene Glycols; D006046:Gold