Talk given by

Prof. Holger Schönherr
Physikalische Chemie I
Universität Siegen
Siegen


Abstract:

Over the past decades, the influence of a multitude of signals present in the microenvironment of cells on their activity and function has been unraveled and led to important breakthroughs, e.g., in the areas of (stem) cell differentiation and cell de-differentiation. The success of research in this field depends crucially on the understanding how cells interact with each other and with the “external” environment. Compared to elaborated micro- and nanopatterns in 2D, the currently available 3D platforms still lack the deterministic control, even though 3D-scaffolds comprising electrospun fibers, self-assembling peptides and other approaches, including printed scaffolds and sophisticated hydrogels, are known and show promising results in tissue engineering applications.

The aim of our work in this context is the development and full nanoscale characterization of polymer-based platforms to afford novel microenvironments for emulating cell - matrix and cell - cell interactions and contacts. The central elements of our approach are polymer brush functionalized microcompartments and hydrogels that are either manufactured in top-down lithography or bottom-up self-assembly approaches. In this presentation the versatile fabrication of functional, stimuli-responsive responsive biointerface architectures will be elucidated with a particular focus on the fully decoupled, i.e. individually independent control of biochemical functionality, nanomechanical properties and topography, afforded by recently established polymer brush approaches with a novel concept for micro-nano structuring in 3D. By exploiting a novel concept of guided and spontaneous assembly of polymer brush functionalized polymeric microobjects unprecedented complex 3D microenvironments were obtained, to which various types of cells react differently, depending on the selected cues provided. The nanoscale characterization of structure and mechanical properties of the brush modified surfaces by AFM will receive particular attention.

Selected references:

[1] Inga Lilge, and Holger Schönherr, Angew. Chem. Int. Ed. Engl. 2016, 55, 13114 –13117. "Block copolymer brushes for completely decoupled control of determinants of cell-surface interactions"

[2] Inga Lilge, Siyu Jiang, Daniel Wesner and Holger Schönherr, ACS Applied Materials & Interfaces. 2016, 8, 23591–23603. “The Effect of Size and Geometry of Poly(acrylamide) Brush-Based Micro-Patterns on the Behavior of Cells”

[3] Ekram Wassel, Daniel Wesner and Holger Schönherr Europ. Polym. J. 2017, 89, 440–448. “Colloidal force probe study of poly(di(ethylene glycol)methylether methacrylate) homopolymer brush layers in aqueous media at different temperatures”

[4] Yvonne Voß, Ekram Wassel, Siyu Jiang, Qimeng Song, Sergey I. Druzhinin, and Holger Schönherr Macromol. Biosci. 2017 in press. DOI: 10.1002/mabi.201600337. “Thin Poly(di(ethylene glycol)methyl ether methacrylate) Homopolymer Brushes Allow Controlled Adsorption and Desorption of PaTu 8988t Cells”

[5] Inga Lilge and Holger Schönherr, Polymer 2016, 98, 409 - 420 (invited, special issue Polymer Brushes). “Synthesis and characterization of well-defined ligand-terminated block copolymer brushes for multifunctional biointerfaces”

[6] Inga Lilge and Holger Schönherr, Langmuir 2016, 32, 838–847. “Control of cell attachment and spreading on poly(acrylamide) brushes with varied grafting density”

[7] Ekram Wassel, Siyu Jiang, Qimeng Song, Stephan Vogt, Gilbert Nöll, Sergey I. Druzhinin and Holger Schönherr, Langmuir 2016, 32, 9360–9370. “Thickness Dependence of Bovine Serum Albumin Adsorption on Thin Thermoresponsive Poly(diethylene glycol) Methyl ether Methacrylate Brushes by Surface Plasmon Resonance Measurements”

[8] Holger Schönherr, Imaging Polymer Morphology Using Atomic Force Microscopy in Morphology: Principles, Characterization, and Processing, Editor: Q. Guo, John Wiley & Sons, Inc. 2016

[9] Nicole Hain, Daniel Wesner, Sergey I. Druzhinin, and Holger Schönherr, Langmuir 2016, 32, 11155–11163. “Surface nanobubbles studied by time resolved fluorescence microscopy methods combined with AFM: The impact of surface treatment on nanobubble nucleation”

[10] Stephan Handschuh-Wang, Daniel Wesner, Tao Wang, Pengyu Lu, Katrin-Stephanie Tücking, Simon Haas, Sergey I. Druzhinin, Xin Jiang, and Holger Schönherr Macromolecular Chemistry and Physics 2017, 218, 1600454. “Determination of the Wall Thickness of Block Copolymer Vesicles by Fluorescence Lifetime Imaging Microscopy”

[11] Scanning Force Microscopy of Polymers (Springer Laboratory), 2010, Holger Schönherr, G. Julius Vancso, ISBN 978-3-642-01230-3, SPRINGER.