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This paper presents cell culture substrates in the form of microcontainer arrays with overlaid surface topographies, and a technology for their fabrication. The new fabrication technology is based on microscale thermoforming of thin polymer films whose surfaces are topographically prepatterned on a micro- or nanoscale. For microthermoforming, we apply a new process on the basis of temporary back moulding of polymer films and use the novel concept of a perforated-sheet-like mould. Thermal micro- or nanoimprinting is applied for prepatterning. The novel cell container arrays are fabricated from polylactic acid (PLA) films. The thin-walled microcontainer structures have the shape of a spherical calotte merging into a hexagonal shape at their upper circumferential edges. In the arrays, the cell containers are arranged densely packed in honeycomb fashion. The inner surfaces of the highly curved container walls are provided with various topographical micro- and nanopatterns. For a first validation of the microcontainer arrays as in vitro cell culture substrates, C2C12 mouse premyoblasts are cultured in containers with microgrooved surfaces and shown to align along the grooves in the three-dimensional film substrates. In future stem-cell-biological and tissue engineering applications, microcontainers fabricated using the proposed technology may act as geometrically defined artificial microenvironments or niches.Electronic supplementary materialThe online version of this article (doi:10.1007/s10544-011-9588-5) contains supplementary material, which is available to authorized users.

Hopes are high that such structures can be utilized in a mold to generate a rough surface that amplifies the hydrophobic properties of the material used in the replication process. The presented experiments are first steps towards a deeper understanding of the emergence of microstructures, the possible variations and the reproducibility thereof. The ripple structure is discussed for about 30 years, and the proposed models do not predict all experimental results. This research gives new experimental data on which the proposed models can be validated. The next section will present some of these models.

Groenendijk studied Mechanical Engineering at the University of Twente and graduated in the field of active vibration isolation. In his PhD project he worked on femtosecond pulsed materials processing and especially the fabrication of super hydrophobic surfaces by such lasers. Together with two partners he started a spin-off company called Lightmotif that will further develop this technique. The company also offers applications research for a broader range of ultrashort pulsed laser processes.• THE AUTHORThe chair of Applied Laser Technology of the University of Twente, The Netherlands, is performing research into applications of ultrashort pulsed lasers for micromachining. In a recent project, PhD student Max Groenendijk developed a method for the production of super water repellant surfaces by injection molding. The core of this technique is the structuring of mold surfaces by micro and nanometer sized textures, using a femtosecond pulsed laser.