Gold-Tipped Elastomeric Pillars for Cellular Mechanotransduction

We describe a technique for the fabrication of arrays of elastomeric pillars whose top surfaces are treated with selective chemical functionalization to promote cellular adhesion in cellular force transduction experiments. The technique involves the creation of a rigid mold consisting of arrays of circular holes into which a thin layer of Au is deposited while the top surface of the mold and the sidewalls of the holes are protected by a sacrificial layer of Cr. When an elastomer is formed in the mold, the Au adheres to the tops of the molded pillars. This can then be selectively functionalized with a protein that induces cell adhesion, while the rest of the surface is treated with a repellent substance. An additional benefit is that the tops of the pillars can be fluorescently labeled for improved accuracy in force transduction measurements.