The final cell concentration can be optimized based on different cell types. We recommend preparing cell suspension at the following concentration for:
3D cell culture:5-2 x 106 cells/mL (the cell suspension needs to mix with VitroGel solution at the 4:1 ratio (VitroGel solution: Cell suspension at 4:1 v/v), which make the final cell concentration in the hydrogel  1-4 x 105 cells/mL)
2D hydrogel coating: 1-5 x 105 cells/mL