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Abstract We report a novel glycan array architecture that binds the mannose‐specific glycan binding protein, concanavalin A (ConA), with sub‐femtomolar avidity. A new radical photopolymerization developed specifically for this application combines the grafted‐from thiol–(meth)acrylate polymerization with thiol–ene chemistry to graft glycans to the growing polymer brushes. The propagation of the brushes was studied by carrying out this grafted‐to/grafted‐from radical photopolymerization (GTGFRP) at >400 different conditions using hypersurface photolithography, a printing strategy that substantially accelerates reaction discovery and optimization on surfaces. The effect of brush height and the grafting density of mannosides on the binding of ConA to the brushes was studied systematically, and we found that multivalent and cooperative binding account for the unprecedented sensitivity of the GTGFRP brushes. This study further demonstrates the ease with which new chemistry can be tailored for an application as a result of the advantages of hypersurface photolithography.
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Carbohydrate‐Based Polymer Brushes Prevent Viral Adsorption on Electrostatically Heterogeneous Interfaces
Abstract Chemical heterogeneity on biomaterial surfaces can transform its interfacial properties, rendering nanoscale heterogeneity profoundly consequential during bioadhesion. To examine the role played by chemical heterogeneity in the adsorption of viruses on synthetic surfaces, a range of novel coatings is developed wherein a tunable mixture of electrostatic tethers for viral binding, and carbohydrate brushes, bearing pendant α‐mannose, β‐galactose, or β‐glucose groups, is incorporated. The effects of binding site density, brush composition, and brush architecture on viral adsorption, with the goal of formulating design specifications for virus‐resistant coatings are experimentally evaluated. It is concluded that virus‐coating interactions are shaped by the interplay between brush architecture and binding site density, after quantifying the adsorption of adenoviruses, influenza, and fibrinogen on a library of carbohydrate brushes co‐immobilized with different ratios of binding sites. These insights will be of utility in guiding the design of polymer coatings in realistic settings where they will be populated with defects.
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- Award ID(s):
- 1647837
- PAR ID:
- 10078195
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Rapid Communications
- Volume:
- 40
- Issue:
- 1
- ISSN:
- 1022-1336
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract We report a novel glycan array architecture that binds the mannose‐specific glycan binding protein, concanavalin A (ConA), with sub‐femtomolar avidity. A new radical photopolymerization developed specifically for this application combines the grafted‐from thiol–(meth)acrylate polymerization with thiol–ene chemistry to graft glycans to the growing polymer brushes. The propagation of the brushes was studied by carrying out this grafted‐to/grafted‐from radical photopolymerization (GTGFRP) at >400 different conditions using hypersurface photolithography, a printing strategy that substantially accelerates reaction discovery and optimization on surfaces. The effect of brush height and the grafting density of mannosides on the binding of ConA to the brushes was studied systematically, and we found that multivalent and cooperative binding account for the unprecedented sensitivity of the GTGFRP brushes. This study further demonstrates the ease with which new chemistry can be tailored for an application as a result of the advantages of hypersurface photolithography.more » « less
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Abstract Block copolymer brushes are of great interest due to their rich phase behavior and value‐added properties compared to homopolymer brushes. Traditional synthesis involves grafting‐to and grafting‐from methods. In this work, a recently developed “polymer‐single‐crystal‐assisted‐grafting‐to” method is applied for the preparation of block copolymer brushes on flat glass surfaces. Triblock copolymer poly(ethylene oxide)‐b‐poly(l‐lactide)‐b‐poly(3‐(triethoxysilyl)propyl methacrylate) (PEO‐b‐PLLA‐b‐PTESPMA) is synthesized with PLLA as the brush morphology‐directing component and PTESPMA as the anchoring block. PEO‐b‐PLLA block copolymer brushes are obtained by chemical grafting of the triblock copolymer single crystals onto a glass surface. The tethering point and overall brush pattern are determined by the single crystal morphology. The grafting density is calculated to be ≈0.36 nm−2from the atomic force microscopy results and is consistent with the theoretic calculation based on the PLLA crystalline lattice. This work provides a new strategy to synthesize well‐defined block copolymer brushes.more » « less
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