Paper MN-ThP1
Study on Aspect Ratio Characterization of Polydimethylsiloxane (PDMS) Pillar Arrays for Mechanobiological Traction Forces

Thursday, November 13, 2014, 6:00 pm, Room Hall D

This paper describes a PDMS-based microchip, which consists of a uniform array of ordered arrangement, vertical, elastomeric micropillar(MP), to study the effects of substrate rigidity for mechanobiological traction forces. The PDMS substrates used have the advantage that their stiffness can be easily adjusted by altering their geometry and can precisely detect the biological activities. We developed the micropillar array substrates that a flexible polymer microfabrication technique was applied for manufacturing the elastomeric microstructures of various aspect ratios with height of 2, 4, 8, 12 mm and radius: period ratios of 1:4, 1:5, 1.5:7, and 2:7 mm. The PDMS micropillar was fabricated by replica molding technique for the standard and combines different steps including photolithography, deep reaction ion etching (DRIE) and soft lithography. The experiment result shows that the micropillar array is clean and in good situation. Meanwhile, more complex patterns of pillar rigidity will help us to study the physical and topographical effect of the substrate on mechanobiological behavior. This has significant implications when designing pillar arrays or comparing lateral forces measured on different pillar geometries. Furthermore, the results presented by this research are believed to be useful for biologists who are clarifying similar mechanobiological processes. Consequently, it was investigated how the substrate contribution to the total pillar deflection depends on the Poisson ratio of the material.

Keywords: PDMS, Soft lithography, Micropillar arrays, Aspect-ratio structure