Development of novel 3D scaffolds using BioExtruder by varying the content of hydroxyapatite and silica in PCL matrix for bone tissue engineering

Polycaprolactone (PCL) is considered as a most widely used biodegradable polymers in tissue engineering. But, PCL is also associated with certain limitations like, low stiffness, hydrophobic nature and limited cell affinity. These drawbacks are addressed in the present study by incorporating different wt% of silicon dioxide (SiO 2 ) and hydroxyapatite (HAp) in the PCL matrix. 3D scaffolds were developed using a novel BioExtruder. The physicochemical properties, thermal stability and wettability of the composite scaffolds were studied systematically. Optical and Scanning Electron Microscopic images were analysed for morphological evaluation of the scaffolds. The pore size of the developed scaffolds increased from 290 to 315 μm with increasing SiO 2 content, as examined by scanning electron microscope. An improved compressive modulus of 68.82 MPa was observed for 15 wt% SiO 2 incorporated composite scaffold. The in-vitro degradation study of the composite scaffolds demonstrated an increase in the degradation rate for PCL/HAp scaffolds, while no significant change was observed for SiO 2 incorporated scaffolds. Further, the cytotoxicity and cell proliferation studies were carried out using L929 Mouse Fibroblasts and MG-63 Osteoblasts respectively. The developed scaffolds revealed no toxic effects towards the cellular response and an increase in cell proliferation of ≥90% was observed during 7 days of cell culture. Thus, the scaffolds were proved to be potential candidate for bone tissue engineering application, particularly the scaffold with 10 wt% SiO 2 incorporation into PCL/HAp (75/15) composite has resulted into higher cell proliferative % and improved mechanical strength.