Formation of porous scaffold with phase separation by supercritical CO2 method

Scaffold is a 3D porous structure that is made of different materials, such as synthetic and natural polymers. It plays the role of a synthetic extracellular matrix and permits adhesion, proliferation and differentiation of the cells. Porosity and pore size are the important factors for any 3D scaffold used in bone tissue engineering. In this study, porous scaffolds were prepared by adding hydroxyapatite (HA) nanoparticles as filler to polymeric matrix of polycaprolactone (PCL) blends with two different molecular weights using supercritical CO2 (ScCO2) method. The effect of different parameters such as CO2 pressure, ratio of the polymers and amount of the filler on the scaffold properties were investigated. The results showed that porosity increased with increment of pressure and decreased with increasing the ratio of the high molecular weight PCL to the low molecular weight PCL in the scaffolds and also HA content. Optimum condition for obtaining adequate porous scaffold of PCL/HA occurred at 140 bar and 45ºC.

Keywords:

scaffold , supercritical method , Poly(ε-caprolactone) , tissue engineering , porosity