title: Protein-resistant silicones: incorporation of poly(ethylene oxide) via siloxane tethers.
abstract: Silicones with enhanced protein resistance were prepared by introducing poly(ethylene oxide) (PEO) chains via siloxane tethers (a-c) of varying lengths. Three unique ambifunctional molecules (a-c) having the general formula alpha-(EtO)3Si(CH2)2-oligodimethylsiloxanen-block-poly(ethylene oxide)8-OCH3 (n = 0 (a), 4, (b), and 13 (c)) were prepared via regioselective Rh-catalyzed hydrosilylation. Nine films were subsequently produced by the H3PO4-catalyzed sol-gel cross-linking of a-c each with alpha,omega-bis(Si-OH)polydimethylsiloxane (P, Mn = 3000 g/mol) in varying ratios (1:1, 1:2, and 2:3 molar ratio a, b, or c to P). Films prepared with a 2:3 molar ratio (a-c to P) contained the least amount of un-cross-linked materials, which may migrate to the film surface. For this set of films, surface hydrophilicity and protein resistance increased with siloxane tether length (a-c). These results indicate that PEO was more effectively mobilized to the surface if incorporated into silicones via longer siloxane tethers.
authors.affiliation: Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120, USA.
authors.forename: Ranjini
authors.initials: R
authors.lastname: Murthy
authors.forename: Casey D
authors.initials: CD
authors.lastname: Cox
authors.forename: Mariah S
authors.initials: MS
authors.lastname: Hahn
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Grunlan
mesh_terms: D000327:Adsorption; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D002417:Cattle; D003432:Cross-Linking Reagents / Q000737:chemistry; D008956:Models, Chemical; D044367:Phase Transition; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D012709:Serum Albumin / Q000737:chemistry; D012828:Silicones / Q000737:chemistry*; D012833:Siloxanes / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission; D013055:Spectrophotometry, Infrared / Q000379:methods; D013499:Surface Properties; D013818:Thermogravimetry
chemical_list: D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D011108:Polymers; D012709:Serum Albumin; D012828:Silicones; D012833:Siloxanes; D011092:Polyethylene Glycols