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Lecture: Biomimetic Polymer Networks, the Key to Cell Control?

 

When: 2:30 pm to 3:30pm, Monday, 9 November, 2015

Where: Meeting Room 3, Conference Building, Weijin Road Campus

Speaker: Alan E. Rowan, Professor of Molecular Materials at Radboud University, Nijmegen, The Netherlands.

About the Speaker: Alan E. Rowan is Professor of Molecular Materials at Radboud University, Nijmegen, the Netherlands. His current research interests concern self-assembled and self-organized materials and ‘Processive catalysis’, in which new concepts of macrocyclic catalysts are developed using nature as a model. Professor Rowan has published about 300 scientific articles (including 5 in Nature and Science and more than 10 in the associated nature family) and has an H-index of 52. He is also the co-inventor on 5 patent applications, and the co-founder of 3 spin-off companies (Encapson, Noviotech, and Noviosense) and is the Programme manager for NanoMaterials in Nanonext NL and Chairman of the National Science Foundation Nanostructures Assemblies Programme. The quality and originality of Professor Rowans research has enabled him to receive considerable funding, having being awarded, VIDI and VICI funding, Nanonext funding from Netherlands Organisation for Scientific Research (NWO) and having participated in more than 8 EU projects in the last 10 years. He was awarded the RSC Soft Matter and Biophysics Prize 2014.

About the Lecture: It has long been known that cell behaviour – motility, embryogenesis, stem cell differentiation, wound healing, tumorgenisis, etc – are extremely sensitive to the biophysical cues from the extracellular matrix (ECM) in which the cells reside. Yet in spite of considerable research, it remains unclear exactly how the chemical composition and the properties of the materials on the outside, control cell behaviour on the inside. Once the exact nature of this outside-in communication is unraveled, the full potential of regenerative medicine can be realized. Numerous studies have indicated that ECM biophysical properties essential for controlling cell behaviour include stiffness, the number and type of cell attachments and the pore size. Another biophysical property, unique to all biological ECM materials, that may be essential in controlling cell behaviour, is that of material ‘strain stiffening’; biological ECMs become several orders of magnitude stiffer when strained by the cells. However, to date strain stiffening has hardly been studied since there are virtually no synthetic materials, which exhibit strain stiffening and none that stiffen at the very low forces a cell can apply. In 2012 my group discovered a new class of biomimetic materials, based upon helical stiff peptidopolyisocyanides (PICs). Hydrogels based on oligo (ethylene glycol) grafted polyisocyanopeptides mimic the biological ECMs. These extremely stiff helical polymers, form gels upon warming at concentrations as low as 0.005 %-wt polymer, with materials properties almost identical to these of intermediate filaments and extracellular matrices. The macroscopic behavior of these gels can be described in terms of the molecular properties of the basic stiff helical polymer and a multi-step hierarchical self-assembly, which results in strain stiffening. For the first time, we now have a tool that allows us to examine cell behavior in a synthetic ECM. Preliminary results of experiments with the PIC-gels indicate that stem cell fate can indeed be directed by varying the ‘strain stiffening’ alone.

Organizer: Chemical Engineering and Chemistry Synergy Innovation Center

All students and staff of Tianjin University are welcome.