title: Polymeric substrates with tunable elasticity and nanoscopically controlled biomolecule presentation.
abstract: Despite tremendous progress in recent years, nanopatterning of hydrated polymeric systems such as hydrogels still represents a major challenge. Here, we employ block copolymer nanolithography to arrange gold nanoparticles on a solid template, followed by the transfer of the pattern to a polymeric hydrogel. In the next step, these nanoparticles serve as specific anchor points for active biomolecules. We demonstrate the engineering of poly(ethylene glycol) hydrogel surfaces with respect to elasticity, nanopatterning, and functionalization with biomolecules. For the first time, biomolecule arrangement on the nanometer scale and substrate stiffness can be varied independently from each other. Young's moduli, a measure of the compliance of the substrates, can be tuned over 4 orders of magnitude, including the values for all of the different tissues found in the human body. Structured hydrogels can be used to pattern any histidine-tagged protein as exemplified for his-protein A as an acceptor for immunoglobulin. When cell-adhesion-promoting peptide cRGDfK is selectively coupled to gold nanoparticles, the surfaces provide cues for cell-surface interaction and allow for the study of the modulation of cellular adhesion by the mechanical properties of the environment. Therefore, these substrates represent a unique multipurpose platform for studying receptor/ligand interactions with adhering cells, mechanotransduction, and cell-adhesion-dependent signaling.
authors.affiliation: Department of New Materials and Biosystems, Max Planck Institute for Metals Research, Stuttgart, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Aydin
authors.forename: Ilia
authors.initials: I
authors.lastname: Louban
authors.forename: Nadine
authors.initials: N
authors.lastname: Perschmann
authors.forename: Jacques
authors.initials: J
authors.lastname: Blümmel
authors.forename: Theobald
authors.initials: T
authors.lastname: Lohmüller
authors.forename: Elisabetta Ada
authors.initials: EA
authors.lastname: Cavalcanti-Adam
authors.forename: Tobias L
authors.initials: TL
authors.lastname: Haas
authors.forename: Henning
authors.initials: H
authors.lastname: Walczak
authors.forename: Horst
authors.initials: H
authors.lastname: Kessler
authors.forename: Roberto
authors.initials: R
authors.lastname: Fiammengo
authors.forename: Joachim P
authors.initials: JP
authors.lastname: Spatz
mesh_terms: D002448:Cell Adhesion; D002478:Cells, Cultured; D004548:Elasticity; D006801:Humans; D020100:Hydrogels / Q000737:chemistry; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*
chemical_list: D020100:Hydrogels; D011108:Polymers