Synthetic peptides composed of short sequences within adhesion molecules, referred to as """"""""biomimetic peptides"""""""", have been used to promote cell adhesion on many different types of implant biomaterials. However, our laboratory has shown that hydroxyapatite (HA) biomaterials have the ability to adsorb cell attachment factors from blood/serum, and this caused us to question whether biomimetic approaches-would be helpful on this biomaterial. We opted to explore the use of mimetic peptides of proteins which were not present in high abundance in the blood, but played a major roll in pre-osteoblast cell differentiation. Collagen is the major component of the organic phase of bone, but is not present in large quantities in the blood. Activation of the integrin receptors which bind collagen I cause downstream signaling effects which lead to an increase in osteoblastic markers. Our goal is to test the efficacy of three collagen I mimetic peptides, to see which, if any, has the ability to increase initial cell adhesion or the rate of differentiation. ? ? ?