The protein resistance of silicones prepared with a PEO-silane amphiphile

Hawkins, Melissa L.; Grunlan, Melissa A.

doi:10.1039/c2jm32322b

Cited by 32 publications

(49 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The water-driven restructuring of PEO to the surface of such bulk-modified silicones has been directly observed [47]. In addition, temporally measuring the θ static of a deposited water droplet has been shown to effectively monitor reorganization of PEO to the surface-water interface [44–46]. Therefore, the 15 bulk-modified silicones and unmodified silicone control (0.14 ± 0.01 mm thick by electronic caliper) were evaluated by measuring θ static of water droplets over a 5 min period.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Protein resistance efficacy of PEO-silane amphiphiles: Dependence on PEO-segment length and concentration

et al. 2016

Self Cite

View full text Add to dashboard Cite

In contrast to modification with conventional PEO-silanes (i.e. no siloxane tether), silicones with dramatically enhanced protein resistance have been previously achieved via bulk-modification with poly (ethylene oxide) (PEO)-silane amphiphiles α-(EtO)3Si(CH2)2-oligodimethylsiloxane13-block-PEOn-OCH3 when n = 8 and 16 but not when n = 3. In this work, their efficacy was evaluated in terms of optimal PEO-segment length and minimum concentration required in silicone. For each PEO-silane amphiphile (n = 3, 8, and 16), five concentrations (5, 10, 25, 50, and 100 μmol per 1 g silicone) were evaluated. Efficacy was quantified in terms of the modified silicones’ abilities to undergo rapid, water-driven surface restructuring to form hydrophilic surfaces as well as resistance to fibrinogen adsorption. Only n = 8 and 16 were effective, with a lower minimum concentration in silicone required for n = 8 (10 μmol per 1 g silicone) versus n = 16 (25 μmol per 1 g silicone). Statement of Significance Silicone is commonly used for implantable medical devices, but its hydrophobic surface promotes protein adsorption which leads to thrombosis and infection. Typical methods to incorporate poly(ethylene oxide) (PEO) into silicones have not been effective due to the poor migration of PEO to the surface-biological interface. In this work, PEO-silane amphiphiles – comprised of a siloxane tether (m = 13) and variable PEO segment lengths (n = 3, 8, 16) – were blended into silicone to improve its protein resistance. The efficacy of the amphiphiles was determined to be dependent on PEO length. With the intermediate PEO length (n = 8), water-driven surface restructuring and resulting protein resistance was achieved with a concentration of only 1.7 wt%.

show abstract

Section: Resultsmentioning

confidence: 99%

“…Adsorbed fibrinogen plays a well-established role in the initiation of surface-induced thrombosis [49,50] and is commonly used to evaluate material thrombogenicity in vitro [14,27,34,46,47,51]. Oeveren et al concluded that fibrinogen adsorption was one of the most reliable methods to predict thrombogenicity for many materials [52].…”

Section: Resultsmentioning

confidence: 99%

Protein resistance efficacy of PEO-silane amphiphiles: Dependence on PEO-segment length and concentration

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…61-66 Its use in evaluating the thromboresistance of materials in vitro has also been well established. 26, 40, 46-49, 53, 54, 63, 67-71 Adsorption of HF onto surface-grafted silicon wafers was measured by quartz crystal microbalance with dissipation monitoring (QCM-D) (Figure 4). QCM-D has been widely used for measuring adsorption of proteins on low-fouling grafted monolayers and thin films.…”

Section: Resultsmentioning

confidence: 99%

“…44, 46, 48, 49 Adsorption of fluorescently-labeled HF (100 μg/mL) was measured on silicone in terms of absolute fluorescent intensity (Table S3) and that normalized to unmodified silicone (Figure 7). The unmodified silicone, due to its high hydrophobicity, resulted in characteristically high protein adsorption.…”

Section: Resultsmentioning

confidence: 99%

Enhancing the protein resistance of silicone via surface-restructuring PEO–silane amphiphiles with variable PEO length

et al. 2015

View full text Add to dashboard Cite

Silicones with superior protein resistance were produced by bulk-modification with poly(ethylene oxide) (PEO)-silane amphiphiles that demonstrated a higher capacity to restructure to the surface-water interface versus conventional non-amphiphilic PEO-silanes. The PEO-silane amphiphiles were prepared with a single siloxane tether length but variable PEO segment lengths: α-(EtO)3Si(CH2)2-oligodimethylsiloxane13-block-poly(ethylene oxide)n-OCH3 (n = 3, 8, and 16). Conventional PEO-silane analogues (n = 3, 8 and 16) as well as a siloxane tether-silane (i.e. no PEO segment) were prepared as controls. When surface-grafted onto silicon wafer, PEO-silane amphiphiles produced surfaces that were more hydrophobic and thus more adherent towards fibrinogen versus the corresponding PEO-silane. However, when blended into a silicone, PEO-silane amphiphiles exhibited rapid restructuring to the surface-water interface and excellent protein resistance whereas the PEO-silanes did not. Silicones modified with PEO-silane amphiphiles of PEO segment lengths n = 8 and 16 achieved the highest protein resistance.

show abstract

“…Bulk-modification of a silica-reinforced silicone with PEO-silane amphiphile ( m = 13) likewise demonstrated water-driven surface-restructuring and protein resistance. 32 Atomic force microscopy (AFM) analysis verified that PEO segments of the PEO-silane amphiphile ( m = 13) were driven to the surface-water interface of the silicone. 33 In this way, PEO-silane amphiphiles functioned as effective “surface-modifying additives” (SMAs) 34 for silicones.…”

Section: Introductionmentioning

confidence: 97%

Anti-protein and anti-bacterial behavior of amphiphilic silicones

et al. 2017

Self Cite

View full text Add to dashboard Cite

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.

show abstract

The protein resistance of silicones prepared with a PEO-silane amphiphile

Cited by 32 publications

References 39 publications

Protein resistance efficacy of PEO-silane amphiphiles: Dependence on PEO-segment length and concentration

Protein resistance efficacy of PEO-silane amphiphiles: Dependence on PEO-segment length and concentration

Enhancing the protein resistance of silicone via surface-restructuring PEO–silane amphiphiles with variable PEO length

Anti-protein and anti-bacterial behavior of amphiphilic silicones

Contact Info

Product

Resources

About