Background & objectives : T he main goal of tissue engineering is regeneration and restoration of damaged tissues and organs, besides being used in medicine . Scaffolds are the main segments for tissue engineering, and plasma surface modification is one of the modern methods used for surface modification on polymer scaffolds. The aim of this study was to evaluate the effect of nano-fibers with different densities on fibroblasts' behavior besides the plasma surface modification.

  Methods : Poly Ɛ-Caprolactone nano-fibers (PCL) were developed by an electro-spinning technique at different collecting times. These nano-fibers were then modified by oxygen plasma. Cellular attachment to the nano-fiber and their morphology were evaluated using scanning electron microscope (SEM) and cellular activities were also studied by 3-[4,5-dimethylthiazol- 2-yl]-2,5 diphenyltetrazolium bromide (MTT). Scaffold biocompatibility test was assessed using inverted microscope.

  Results : Scanning electron microscope images of nano-fibers showed that increase in time of spinning has significantly heighten fiber density, on the other hand plasma surface modification of nano-fibers had significant effects on their respective biocompatibilities. The result of cell culture showed that nano-fiber could support the cellular growth and replication by developing 3-dimensional topography.

  Conclusion : Our results showed that increase in time of spinning and using plasma surface modification of nano-fibers by oxygen plasma would result in providing surface with the highest similarity to the extracellular matrix.