Porous Crosslinked Polycaprolactone Hydroxyapatite Networks for Bone Tissue Engineering

ABSTRACT

In this study, porous scaffolds were produced by a thermal crosslinking of polycaprolactone diacrylate in the presence of hydroxyapatite (HA) and particulate leaching technique with sodium chloride as the water soluble porogen for bone tissue engineering applications. The prepared scaffolds were characterized using techniques such as Field Emission Scanning Electron Microscopy, Differential Scanning Calorimetry, and Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy. Moreover, dynamic mechanical properties were investigated using Dynamic Mechanical Thermal Analysis. The obtained scaffolds present a porous structure with interconnected pores and porosity around 73%. It was found that the incorporation of HA particles to polycaprolactone (PCL) matrix resulted in an increased crystallinity. Moreover, both the storage modulus (E′) and glass transition temperature (T(g)) increased, while the loss factor (tan δ) decreased due to the hindrance of the HA particles to the mobility of polymer segments. Cytocompatability of the scaffolds was assessed by MTT assay and cell attachment studies. Osteoconductivity of the scaffolds was investigated with cells alkaline phosphatase extraction. The levels of alkaline phosphatase activity were found to be higher for PCL/HA network scaffold than for PCL network scaffold. In addition, cytocompatibility of the PCL/HA network scaffold indicated no toxicity, and cells were attached and spread to the scaffold walls.