Biomimetic Apatite-coated PCL Scaffolds: Effect of Surface Nanotopography on Cellular Functions

Abstract
In this study, polycaprolactone (PCL) scaffolds, consisting of agglomerated microspheres with nanotopographic surface structures, were fabricated by the freeze-drying method. These scaffolds were coated with bone-like apatite by using a calcium phosphate solution similar to saturated simulated body fluid (10× SBF-like) in two different immersion periods (6 and 24 h). Scanning electron microscopic views of the 6-h treatment in 10× SBF-like solution showed formation of calcium phosphate nucleation sites on the PCL scaffolds, while the apatite particles formed characteristic cauliflower-like morphology after 24 h. The X-ray diffraction (XRD) data showed that the mineral phase was made of hydroxyapatite (HA). The osteogenic activity of untreated and SBF-treated PCL scaffolds was examined by pre-osteoblastic MC3T3 cell culture studies. Cells had attached and spread on both the PCL scaffolds and the 6-h SBF immersion-treated scaffolds.