In this study, a series of membranes with different amino group densities were prepared to investigate the surface properties of the novel poly(gamma-amino-epsilon-caprolactone-co-epsilon-caprolactone) (NPCL) copolymer synthesized by our laboratory. Meanwhile, the human mesenchymal stem cells' (hMSCs) behavior on those membranes was examined. The molecular characteristics of the NPCL copolymers were characterized by nuclear magnetic resonance (NMR), size exclusion chromatography (SEC), and differential scanning calorimetry (DSC). Surface properties of membranes were characterized by water contact angle analysis, X-ray photoelectron spectroscopy analysis (XPS), and atomic force microscopy (AFM). It was found that the incorporation of amino groups to the poly(epsilon-caprolactone) (PCL) backbone resulted in an augmented wettability, a decreased crystallinity, and also an increased surface roughness on the NPCL membranes. In vitro cell experiments showed a significant enhancement in hMSCs' adhesion, proliferation, and osteogenic differentiation on NPCL membranes compared with virgin PCL membrane, and demonstrated that surface properties of membrane played an important role in tailoring cell behavior. (C) 2011 Elsevier Inc. All rights reserved.