(14j) Effect of the First Layer on Polyelectrolyte Multilayer Properties and Function

Polyelectrolyte multilayers have been attracting attention due to the ease of preparation and potential for tailorable properties. We are interested in polyelectrolyte multilayers as coatings for orthopedic implants. Polyelectrolyte multilayers were prepared with bone morphogenetic protein 2 as the first layer and control systems were prepared with a polycation as the first layer. Significantly different surface roughness was observed between the two, which impacted the proliferation and differentiation of pre-osteoblasts cultured on both coatings. Furthermore, it was observed that processing conditions such as deposition solution pH and and salt concentration impacted greatly this difference in surface roughness and also affected other physical properties. Techniques including quartz crystal microbalance with dissipation, atomic force microscopy and goniometry were employed to try to understand the observed phenomena. We will discuss our findings and present thought regarding potential mechanisms.