Adhesion of osteoblast-like cells on electrodeposited calcium phosphate coatings

Calcium phosphate (Ca-P) ceramics coated on titanium is extensively used in orthopedic implants. This is attributed to the advantages of titanium offering desirable mechanical properties and to the biocompatibility of Ca-P ceramics. Ca-P compounds have excellent biocompatibility due to their compositional similarity to natural bone mineral and exhibit a surface chemistry that promotes the formation of bone-like hydroxyapatite on its surface. Electrochemical deposition (ECD) is the most frequently used technique to produce Ca-P coatings. The parameters of electrochemical deposition significantly affect the thickness, chemical composition, and morphology of the deposited coating. The morphology of the deposited coatings is a critical issue since it strongly influences the interaction with tissue cells. The present work has studied the influence of deposition time (1, 2, 3, 5, and 30 min) on the thickness and the morphology of the deposited coatings by ion milling system and scanning electron microscopy (SEM), respectively. Tissue compatibility is investigated by assessing the interactions of bone-like SaOs cells with the Ca-P surface coatings; the cells’ behaviour was observed via SEM and fluorescence microscopy using immunostaining after 2 days and 7 days culture. At lower deposition time a smooth coating with minimum roughness deposited. By increasing the deposition time the surface roughness increases as well. Different morphologies with different roughness significantly affected the cellular behaviour. SaOs cells can grow and adhere to the smooth coating very well and displaying high spreading area. While, on the rough coatings cells appeared less viable and many rounded cells were observed.