Microfluidic micropillar arrays for 3D cell culture

Cell-based assays are one of the most important steps to select huge amount of drug candidates in drug discov- ery. To get more credible assay results, cell culture in the form of microscale environment and three-dimension has been exploited by microfluidic hydrodynamic focusing. However, the method still needs an enhanced reliability of scaffold formation and fast cell immobilization in a microchannel. In this report, we fabricated a microfluidic micropillar arrays (MMA) platform for cell culture using a poly(dimethylsiloxane) (PDMS) replica molding process. Peptide hydrogel and Matrigel were nicely patterned along the micropillars by surface tension. In addition, a linear concentration gradient pro- file was presented in a stripe-shaped Matrigel matrix and the simulation result with computational fluid dynamics (CFD) solver was corresponded to the experimental profile. The MMA platform was successfully applied to the hepatocellular carcinoma cell (HepG2) culture for 2 days.