Tailor-made Surfaces & Bioinspired Materials
The ability of living organisms (i.e. living cells) to respond to various environmental changes with a high specificity is as impressive as it is difficult to predict. For the integration of these advanced sensorial systems into artificial lab-on-a-chip devices (cell-chips), the spatially controlled attachment and proliferation of living cells within microscale dimensions on solid substrates is perhaps one of the key challenges. Next to the important role of well-defined cell arrays in the automatization and acceleration of the drug discovery process, the reduction of on-chip cell colony sized down to single cell assays and the incorporation of microfluidic and sensorial systems will facilitate the investigation and perhaps enhance the understanding of cell-to-cell communication pathways.
By a simple convergent synthesis strategy, we designed bioactive, non-toxic poly(dimethylacrylamide), PDMAA polymers that carry a peptide ligand, which is recognized by receptors present in the plasma membrane of eucaryotic cells. The polymer is covalently linked to a solid substrate by simple photo-chemistry means using a surface-attached benzophenone functional site. A simple polymer synthesis combined with an efficient surface modification strategy, including lithographically structured surfaces, makes this design of bioactive interfaces very interesting for a large number of possible applications.
In a parallel work, we developed substrate-supported, polymerized peptide-amphiphile monolayers that expose a similar peptide-ligand (RGDS) in a very controlled fashion. Cells respond to these monolayers in a concentration-dependent manner, and possible applications of these supramolecular architectures may be their use as model-surfaces to study cell-material interactions.