Anti-protein and anti-bacterial behavior of amphiphilic silicones

Abstract

Silicones with improved water-driven surface hydrophilicity and anti-biofouling behavior were achieved when bulk-modified with poly(ethylene oxide) (PEO) –silane amphiphiles of varying siloxane tether length: α-(EtO)3Si-(CH2)2-oligodimethylsiloxanem-block-poly(ethylene oxide)8-OCH3 (m = 0, 4, 13, 17, 24, and 30). A PEO8-silane [α-(EtO)3Si-(CH2)3-PEO8-OCH3] served as a conventional PEO-silane control. To examine anti-biofouling behavior in the absence versus presence of water-driven surface restructuring, the amphiphiles and control were surface-grafted onto silicon wafers and used to bulk-modify a medical-grade silicone, respectively. While the surface-grafted PEO-control exhibited superior protein resistance, it failed to appreciably restructure to the surface-water interface of bulk-modified silicone and thus led to poor protein resistance. In contrast, the PEO-silane amphiphiles, while less protein-resistant when surface-grafted onto silicon wafers, rapidly and substantially restructured in bulk-modified silicone, exhibiting superior hydrophilicity and protein resistance. A reduction of biofilm for several strains of bacteria and a fungus was observed for silicones modified with PEO-silane amphiphiles. Longer siloxane tethers maintained surface restructuring and protein resistance while displaying the added benefit of increased transparency.

Mussel‐Inspired, Surface‐Attachable Initiator for Grafting of Antimicrobial and Antifouling Hydrogels

“…These results underlined a promising use of MPHMG‐ co ‐PEG hydrogel coatings to prevent transmitting diseases and nosocomial infections with the wide utilization of biomedical devices/implants. Covalently bonded antimicrobial coatings have been prepared by various surface chemistry such as silane coupling, ozone oxidation, and plasma activation . Comparing with those surface modification techniques, our DOPV could attach to virtually any kind of surfaces including metal, organic, and inorganic substrates.…”

Thromboresistance of Polyurethanes Modified with PEO‐Silane Amphiphiles

“…As SMAs in such a silicone, they showed effective and sustained water-driven surface restructuring for enhanced hydrophilicity and resistance to protein adsorption ( Figure 1b). [46,47,50] As this was not observed with analogous, nonamphiphilic PEO-silanes [(α-(EtO) 3 -Si-(CH 2 ) 3 -PEO n -CH 3 )], [48,50,52] the unique restructuring capacity of PEO-SAs was attributed to the flexibility and chemical compatibility of the ODMS tether with the silicone matrix. Additional studies evaluated concentration (0-100 µmol per 1 g of silicone) as well as the structure-property relationship of PEO-SAs of different PEO length (n; n = 3-16), [52,53] ODMS length (m; m = 0-30), [48] and crosslinkability (i.e., with or without TES group).…”

“…[46,47,50] As this was not observed with analogous, nonamphiphilic PEO-silanes [(α-(EtO) 3 -Si-(CH 2 ) 3 -PEO n -CH 3 )], [48,50,52] the unique restructuring capacity of PEO-SAs was attributed to the flexibility and chemical compatibility of the ODMS tether with the silicone matrix. Additional studies evaluated concentration (0-100 µmol per 1 g of silicone) as well as the structure-property relationship of PEO-SAs of different PEO length (n; n = 3-16), [52,53] ODMS length (m; m = 0-30), [48] and crosslinkability (i.e., with or without TES group). [46,50] Generally, PEO-SA SMAs demonstrated increased surface hydrophilicity and resistance to human fibrinogen (HF) adsorption (from a simple aqueous solution) at concentrations as low as 10 µmol g −1 .…”

“…[45,46] Our group has developed PEO-silane amphiphile (PEO-SA) SMAs, originally for the bulk-modification of condensation-cure silicones. [46][47][48][49][50][51][52][53] The PEO-SA contains a triethoxysilane (TES) group, a flexible, hydrophobic oligo(dimethyl siloxane) (ODMS) tether, and a PEO segment: (Figure 1a). [49] The TES group is capable of crosslinking when incorporated into a condensation-cure silicone.…”

Combinatorial Polyacrylamide Hydrogels for Preventing Biofouling on Implantable Biosensors

“…In contrast, "passive" coating strategies that modify the chemistry at the interface of the devices and bodily fluids are scalable, tunable, and inexpensive. The "gold standard" materials used for passive anti-biofouling coatings are poly(ethylene glycol) (PEG) 13 and its derivatives [14][15][16] , which form a tight hydration layer through hydrogen bonding with water that is hypothesized to contribute to anti-biofouling properties 17 .…”