Fabrication and application of salicin-polycaprolactone 3D-printed scaffold in the healing of femur bone defects

Abstract

Polycaprolactone (PCL) is a suitable material for bone repair due to good biocompatibility and mechanical properties. However, low bioactivity and hydrophobicity pose major challenges for its biomedical applications. To overcome these limitations, PCL-based scaffolds loaded with bioactive agents have been developed. Salicin (Sal) is an anti-inflammatory and analgesic herbal glycoside with osteogenic potential. In the present study, we aimed to produce a Sal-laden PCL (PCL–Sal) scaffold for bone healing applications. Three-dimensional scaffolds were produced and their biocompatibility, and physical-chemical characteristics were determined. The osteogenic potential of the PCL (PCL) and PCL–Sal scaffolds was evaluated using bone marrow mesenchymal stem cells (BMSCs). Scaffolds were implanted into a 5 mm bone defect created in the femur of adult rats, and the new bone fraction was determined using micro-computed tomography scanning at one-month follow-up. PCL–Sal scaffold had a structure, porosity, and fiber diameter suitable for bone construction. It also possessed a higher rate of hydrophilicity and bioactivity compared to the PCL, providing a suitable surface for the proliferation and bone differentiation of BMSCs. Furthermore, PCL–Sal scaffolds showed a higher capacity to scavenge free radicals compared to PCL. The improved bone healing potential of the PCL–Sal scaffold was also confirmed according to in vivo implantation results. Our findings revealed that the Sal-laden implant could be considered for bone repair due to desirable characteristics of Sal such as hydrophilicity, surface modification for cell attachment, and antioxidant properties.