Influence of structured wafer surfaces on the characteristics of Caco-2 cells.

Currently there is an increasing demand for high-throughput methods to identify and to verify the potential of new drug candidates. Cell-based microelectronic biosensors might be powerful tools for rapid screening assays. However, reliable cultivation of cells is influenced by the material characteristics and the surface topography of the wafers serving as growth supports. In order to investigate the influence of micropatterned structures on cell viability, Caco-2 cells were seeded on silicon wafers featuring trench/mesa patterns obtained by lithography and reactive ion etching. Besides determination of the cell growth pattern by electron microscopic inspection, the adherence of cells on different patterned silicon wafers and the formation of the tight junctional network was investigated. Microstructured trench/mesa patterns, especially their lateral distances, remarkably influenced the adhesion and proliferation behavior of Caco-2 cells. Lateral distances below the average cell diameter were easily overgrown by the cells, whereas dimensions above the average cell diameter increasingly limited cell proliferation. Notably increased cell growth was observed using trenches with a width of 10-20microm and a trench depth of around 35microm. All in all, the results of this study might improve the production of microstructured biosensors and open up new perspectives concerning the combination of biosensors and microfluidic systems.