Multifunctional gelatin–tricalcium phosphate porous nanocomposite scaffolds for tissue engineering and local drug delivery: In vitro and in vivo studies

•In vitro assay and osteoblast cell line (G292) attachment test showed that the scaffolds were cytocompatible.•The samples were loaded with ZA and its effects on the cell proliferation was investigated in-vitro and in-vivo.•Histopathological results showed that new bone formation was established more than 75% in whole area of the defect after 3 and 4 months.•All findings besides in vitro and in vivo analysis, recommend gelatin/nano beta-tricalcium phosphate/drug scaffolds as a promising three-dimensional environment for bone replacement.