The goal of this work was to evaluate the effect of membrane functionalization with a chemotactic factor on cell recruitment and bone formation in order to develop a bioactive membrane for guided bone regeneration (GBR) applications. To this end. GBR membranes were prepared by electrospinning using poly(epsilon-caprolactone) (PCL) blended with type B-gelatin, and functionalized with stromal cell derived factor-1 alpha (SDF-1 alpha) via physical adsorption. Firstly, the obtained membranes were evaluated in vitro for SDF-1 alpha release and chemotactic effect on bone marrow stromal cells (BMSCs). Subsequently, in vivo BMSCs recruitment and bone regeneration in response to SDF-1 alpha loaded PCL/gelatin electrospun membranes were assessed in rat cranial defects. The results showed that PCL/gelatin electrospun membranes provided a diffusion-controlled SDF-1 alpha release profile. Furthermore, the membranes loaded with different amounts of SDF-1 alpha (50-400 ng) significantly induced stimulated chemotactic migration of BMSCs in vitro without dose-dependent effects. Eight weeks after implantation in rat cranial defects, SDF-1 alpha loaded membranes yielded a 6-fold increase in the amount of bone formation compared to the bare membranes, albeit that contribution of in vivo BMSCs recruitment to the bone regeneration could not be ascertained. In conclusion, the results of current study indicate the potential for using SDF-1 alpha loaded PCL/gelatin electrospun membrane as a bioactive membrane, which is beneficial for optimizing clinical application of GBR strategies. (C) 2012 Elsevier Ltd. All rights reserved.