Hold on at the Right Spot: Bioactive Surfaces for the Design of Live-Cell Micropatterns. In: Börner HG, Lutz J, editors. Bioactive Surfaces. Berlin: Springer Berlin Heidelberg; 2011. pp. 35-78. [DOI: 10.1007/12_2010_77]

A Synthetic Overview of Preparation Protocols of Nonmetallic, Contact-Active Antimicrobial Quaternary Surfaces on Polymer Substrates

Antibacterial surfaces have been researched for more than 30 years and remain highly desirable. In particular, there is an interest in providing antimicrobial properties to commodity plastics, because these, in their native state, are excellent substrates for pathogens to adhere and proliferate on. Therefore, efficient strategies for converting surfaces of commodity plastics into contact-active antimicrobial surfaces are of significant interest. Many systems have been prepared and tested for their efficacy. Here, the synthetic approaches to such active surfaces are reviewed, with the restriction to only include systems with tested antibacterial properties. The review focuses on the synthetic approach to surface functionalization of the most common materials used and tested for biomedical applications, which effectively has limited the study to quaternary materials. For future developments in the field, it is evident that there is a need for development of simple methods that permit scalable production of active surfaces. Furthermore, in terms of efficacy, there is an outstanding concern of a lack of universal antimicrobial action as well as rapid deactivation of the antibacterial effect through surface fouling.

Microstructured thin Peptide-Polymer Films that Spatially Control the Surface-Attachment of Living Cells

Purpose

The integration of living cells into artificial microdevices requires close control of the interfacial interactions. Functional polymer coatings, such as peptide-polymer monolayers, can be used to guide the specific adhesion of living cells on surfaces in a spatially controlled fashion.

Methods

Silicon surfaces were modified with a protein repellent polymer film composed of poly(dimethylacrylamide) (PDMAA) attached to the peptide cell-recognition motif GRGDSP and a subsequent PDMAA backfill. Microstructuring was achieved through a photolithographical process using surface-bound photoreactive benzophenone. Cell adhesion assays with human fibroblasts were conducted to study the capabilities of this approach to induce a directed outgrowth of living cells and to confine cell colony sizes to single cell arrays.

Results

Human fibroblasts follow the chemically imprinted microstructures on peptide-polymer coated substrates. Lines of GRGDSP-PDMAA with a width of 10 μm induce a highly elongated cell shape whereas round spots with a diameter of 50 μm support only single cells per spot. Starting at a center-to-center distance of 100 μm between single peptide-polymer spots, cells are able to “bridge” non-adhesive PDMAA areas.

Conclusions

Peptide-polymer monolayers can direct the outgrowth and restrict the cell colony size through a variation of the imprinted chemical microstructures.