Effect of high-aspect-ratio microstructures on cell growth and attachment

Smooth muscle cells were cultured on a variety of high-aspect-ratio PMMA, PDMS, and SU-8 microstructures. Three basic microstructures were used in these experiments: columns, holes, and curved surfaces (microlenses). Typical PMMA features were over 500 μm in height, while the SU-8 and PDMS structures averaged 150 μm in height. The smooth muscle cells showed a clear preference for smooth surfaces as compared to the areas containing microstructures, though smooth muscle cells showed the ability to grow on all structures and to attach on the steep sidewalls associated with the microstructures. Smooth muscle cell alignment was not directly improved by the structures, though evidence indicates that smaller structures may be able to do so. Gap dimensions between columns were also shown to be critical with regard to cell spreading and movement