Antifouling polymer layers containing extracellular matrix-derived peptide motifs offer promising new options for biomimetic surface engineering. In this contribution, we report the design of antifouling vascular grafts bearing biofunctional peptide motifs for tissue regeneration applications based on hierarchical polymer brushes. Hierarchical diblock poly(methyl ether oligo(ethylene glycol) methacrylate-block-glycidyl methacrylate) brushes bearing azide groups (poly(MeOEGMA-block-GMA-N3)) were grown by surface-initiated atom transfer radical polymerization (SI-ATRP) and functionalized with biomimetic RGD peptide sequences. Varying the conditions of copper-catalyzed alkyne-azide "click" reaction allowed for the immobilization of RGD peptides in a wide surface concentration range. The synthesized hierarchical polymer brushes bearing peptide motifs were characterized in detail using various surface sensitive physicochemical methods. The hierarchical brushes presenting the RGD sequences provided excellent cell adhesion properties and at the same time remained resistant to fouling from blood plasma. The synthesis of anti-fouling hierarchical brushes bearing 1.2 × 103 nmol/cm2 RGD biomimetic sequences has been adapted for the surface modification of commercially available grafts of woven polyethylene terephthalate (PET) fibers. The fiber mesh was endowed with polymerization initiator groups via aminolysis and acylation reactions optimized for the material. The obtained bioactive antifouling vascular grafts promoted the specific adhesion and growth of endothelial cells, thus providing a potential avenue for endothelialization of artificial conduits.

• Keywords
• RGD peptide, X-ray photoelectron spectroscopy, biomimetic surface, hierarchical bioactive polymer brushes, vascular graft, “click”-chemistry,
• MeSH
• Adsorption MeSH
• Amino Acid Motifs MeSH
• Azides chemistry   MeSH
• Coated Materials, Biocompatible * MeSH
• Biomimetic Materials * MeSH
• Cell Adhesion MeSH
• Cell Division MeSH
• Endothelium, Vascular physiology   MeSH
• Blood Vessel Prosthesis * MeSH
• Click Chemistry MeSH
• Human Umbilical Vein Endothelial Cells MeSH
• Immobilized Proteins MeSH
• Silicon MeSH
• Plasma MeSH
• Blood Proteins MeSH
• Humans MeSH
• Oligopeptides chemistry   MeSH
• Polyethylene Terephthalates chemistry   MeSH
• Polymerization * MeSH
• Surface Properties MeSH
• Guided Tissue Regeneration instrumentation   MeSH
• Glass MeSH
• Materials Testing MeSH
• Thrombosis prevention & control   MeSH
• Gold MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH
• Names of Substances
• arginyl-glycyl-aspartic acid MeSH Browser
• Azides MeSH
• Coated Materials, Biocompatible * MeSH
• Immobilized Proteins MeSH
• Silicon MeSH
• Blood Proteins MeSH
• Oligopeptides MeSH
• Polyethylene Terephthalates MeSH
• Gold MeSH

Nonfouling surfaces capable of reducing protein adsorption are highly desirable in a wide range of applications. Coating of surfaces with poly(ethylene oxide) (PEO), a water-soluble, nontoxic, and nonimmunogenic polymer, is most frequently used to reduce nonspecific protein adsorption. Here we show how to prepare dense PEO brushes on virtually any substrate by tethering PEO to polydopamine (PDA)-modified surfaces. The chain lengths of hetero-bifunctional PEOs were varied in the range of 45-500 oxyethylene units (M(n) = 2000-20,000). End-tethering of PEO chains was performed through amine and thiol headgroups from reactive polymer melts to minimize excluded volume effects. Surface plasmon resonance (SPR) was applied to investigate the adsorption of model protein solutions and complex biologic medium (human blood plasma) to the densely packed PEO brushes. The level of protein adsorption of human serum albumin and fibrinogen solutions was below the detection limit of the SPR measurements for all PEO chains end-tethered to PDA, thus exceeding the protein resistance of PEO layers tethered directly on gold. It was found that the surface resistance to adsorption of lysozyme and human blood plasma increased with increasing length and brush character of the PEO chains end-tethered to PDA with a similar or better resistance in comparison to PEO layers on gold. Furthermore, the chain density, thickness, swelling, and conformation of PEO layers were determined using spectroscopic ellipsometry (SE), dynamic water contact angle (DCA) measurements, infrared reflection-absorption spectroscopy (IRRAS), and vibrational sum-frequency-generation (VSFG) spectroscopy, the latter in air and water.

• MeSH
• Adsorption MeSH
• Biofouling prevention & control   MeSH
• Indoles chemistry   MeSH
• Humans MeSH
• Muramidase chemistry   MeSH
• Polyethylene Glycols chemistry   MeSH
• Polymers chemistry   MeSH
• Serum Albumin chemistry   MeSH
• Water chemistry   MeSH
• Air MeSH
• Gold chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Names of Substances
• Indoles MeSH
• Muramidase MeSH
• polydopamine MeSH Browser
• Polyethylene Glycols MeSH
• Polymers MeSH
• Serum Albumin MeSH
• Water MeSH
• Gold MeSH