Effect of microarchitectural surface of polycaprolactone modified by reactive ion etching on osteogenic differentiation

• The optimal surface topology for improving the cytocompatibility of the implantable material could be realized through the Reactive ion etching technique. • The reactive ion etching plasma-treated material was modified to improve biocompatibility. • The Hill-and-Valley topology is more favorable for cytocompatibility and osteogenic differentiation compared to the Spiky topology. The surface topology of a bioimplantable material is considered to be the most important influencing factor on the cytocompatibility and function. The aim of this study was to compare the cytocompatibility and osteogenic differentiation of polycaprolactone (PCL) surfaces with spiky and hill-and-valley (H-a-V) topologies fabricated by the Plasma reactive ion etching (RIE) technique. The RIE process was performed at a plasma power of 100 W and pressure of 100 mTorr using an oxygen flow rate of 100 sccm for 3 min (for Spiky) and 5 min (for H-a-V). The surface roughness and wettability of PCL were improved with the increase in the RIE treatment time. The focal cell adhesion, migration, and proliferation were increased in the H-a-V group compared to the Spiky group. The cell differentiation values (alkaline phosphatase (ALP) and Alizarin-red staining) were statistically significantly improved in H-a-V compared to those of Spiky. A western blot analysis demonstrated that H-a-V promoted cell differentiation compared to Spiky. These results suggest that the H-a-V topology is more favorable for cytocompatibility and osteogenic differentiation over the Spiky topology.