Effects of composite scaffolds on the cells viability and function. The induced osteoblasts and endothelial cells were separately cultured with the 3 groups of scaffold (30 scaffolds per group for each type of cell) for 7 days before testing. Panels (A) and (C) summarized the Alamar Blue assay for osteoblast and endothelial cell viabilities. Panel (B) plotted alkaline phosphatase activity of osteoblasts on various scaffolds. Panel (D) showed the NO production of endothelial cells on various scaffolds.