Table 2. Preparation of 3D matrices with varying mechanical properties.

Shown is a pipetting scheme for the preparation of collagen-fibronectin matrices with embedded cells. Volumes are shown for the generation of 1 ml of soft and stiff matrix (200 mM).

Collagen matrix calculation scheme	Soft	Stiff
Collagen stock solution	200 µl	200 µl
0.5M ribose solution (in medium)	-	133.3 µl
	leave on ice for 30 min
HEPES (stock = 1 M)	20 µl	20 µl
Fibronectin (stock = 1mg/ml)	20 µl	20 µl
1 M NaOH	4 µl	4 µl
Sodium bicarbonate (7.5% solution)	40 µl	40 µl
Phenol-red free medium (serum-free)	216 µl	82.7µl
	mix collagen working solution 1:1 with cell suspension
Cells in medium	500 µl	500 µl
Final volume of collagen-cell mix	1000 µl