Microfluidic device for generating regionalized concentration gradients under a stable and uniform fluid microenvironment

A relative stable microenvironment is essential for in vitro cell culture. This paper presents a novel cell culture device with multiple arrays of perfusion channels (PCs) to maintain the stability and uniformity of flow fields. Besides, a series of regionalized concentration gradients can be generated by adjusting the relative positions of inlets. The number of circular arrays of PCs have been optimized based on the simulation results. The particle tracking technology has been used to evaluate the changes of flow fields inside the culture chamber as the variation of velocity in medium inlet. The Hela cells, L929 mouse fibroblast cells and HUVEC cells are cultured dynamically in the optimized device. The culture device without PC is used as a comparison. The results of normalized cell density and cell viability indicate that the device with multiple arrays of PCs is more favorable to cell growth. The effects of adjacent position and opposite position of two inlets on generating regionalized concentrations have been demonstrated by FEM simulation analysis and fluorescence distribution. The densities and attachment areas of L929 cells inside one chamber with regionalized concentration gradient have also shown the validity of the designed device.