Design and Validation of a Microfluidic Chip with Micropillar Arrays for Three-dimensional Cell Culture

A microfluidic chip with micropillar arrays for three-dimensional (3D) cell culture was designed and validated. The chip consisted of a polydimethylsiloxane (PDMS) channel plate and a glass cover plate. One cell culture chamber composed of two rows of micropillar arrays and two lateral channels for transporting the culture medium were integrated on the PDMS channel plate. The spacing between micropillars greatly affected the chip performances, which was critical for the design of the chip. In this work, the spacing between micropillars was optimized by numerical simulation and experimental validation. With the optimized microfluidic chip, the mixture of cells and extracellular matrix mimics could be steadily injected into the chamber, the nutrients in the medium from lateral channels could quickly diffuse into the chamber, and the cell metabolites could also timely diffuse out of the chamber. To test the stability of the microenvironment constructed in the optimized chip, neural stem cells were three-dimensionally cultured.