I am doing an adhesion experiment on cancer cells. In various previous literature, researchers used different substrates (Glass, TCPS, Hydrogels). Sometimes they do the coating on the substrates with BM proteins (fibronectin/ laminin /IV collagen) and sometimes they don't, before seeding the cells on the substrate. How to decide the need to do coating or not to do coating on the substrate to see the substrate stiffness effect on the phenotype of the cells.