Fabrication of Freestanding 1-D PDMS Microstructures Using Capillary Micromolding

A method to create freestanding, biocompatible polydimethylsiloxane (PDMS) microstructures is presented. First, capillary flow through micro channels on silicon (Si) substrates is used to create high fidelity PDMS structures that are a few μm wide and deep but several mm long (length to width/depth ≈ 500:1). Next, an improvised procedure is employed to remove the cured PDMS microstructures from the Si substrate without damaging them. The method is used to create extremely sensitive cantilever beams with stiffness less than 0.1 pN/μm, and micro platforms for cell biology studies. The PDMS microstructures created using this method have applications in cell mechanobiology as force and mass sensors.

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