Cell adhesion is mediated by the formation of discrete ligandereceptor bonds (specific interactions) and short ranged interfacial forces as van der Waals, double layer electrostatic andsteric (non-specific interactions), which together contribute to the surface energy of specific and non-specific adhesion gadh [26]. This grows with the density of the ligands adsorbing on the silicon substrate, the density of the receptors expressed on the cell membrane and the affinity of the ligandereceptor bonds.