C.K.M. Ng

Proliferation of Epithelial Cells on PDMS Substrates with Micropillars Fabricated with Different Curvature Characteristics

The present work studied the proliferation of epithelial cells when they were cultivated on substrates with micropillars fabricated with the same height but with different curvature characteristics. A special micro-fabrication method was employed to produce these micropillar substrates. Polyallyldiglycol carbonate (PADC) films were first irradiated by alpha particles and then chemically etched to reach or beyond the “transition” phase to form casts with micrometer-sized pits with the same depth, but with different size and shape. Polydimethylsiloxane (PDMS) replicas of these PADC films then gave the desired substrates with micropillars with the same height but with different curvature characteristics. The micropillars on the PDMS substrates were found to be capable of changing the response of HeLa cells in terms of the percentages of cells in the S-phase and the attached cell numbers after 3-day cell culture. This demonstrated that the proliferation of the HeLa cells could be changed through mechanosensing the substrate curvature.

Fabrication of micropillar substrates using replicas of alpha-particle irradiated and chemically etched PADC films

We proposed a simple method to fabricate micropillar substrates. Polyallyldiglycol carbonate (PADC) films were irradiated by alpha particles and then chemically etched to form a cast with micron-scale spherical pores. A polydimethylsiloxane (PDMS) replica of this PADC film gave a micropillar substrate with micron-scale spherical pillars. HeLa cells cultured on such a micropillar substrate had significantly larger percentage of cells entering S-phase, attached cell numbers and cell spreading areas.