Bioactivity assessment of PLLA/PCL/HAP electrospun nanofibrous scaffolds for bone tissue engineering

Aims: The purpose of this paperwas to fabricate PLLA/PCL nanofibrous scaffolds containing HAP tomimic the native bone extracellular matrix for potential applications as bone tissue engineering scaffolds materials and ultimately to help the repairing of bone defects. Materials and methods: PLLA (MW200 kDa), PCL (MW80 kDa), HAP, dichloromethane, N, N-dimethylformamide; a-MEM, FBS, trypsin-EDTA, penicillin G, streptomycin, beta-sodiumglycerophosphate, L-ascorbic acid, dexamethasone; CCK-8, Alkaline Phosphatase Assay Kit, Mouse Osteocalcin ELISA Kit, MC3T3-E1 cells. PLLA, PCL and HAP were dissolved in the solution of DCM and DMF to fabricate nanofibrous scaffolds through electrospinning. The morphology of the scaffolds was investigated with SEM, while the diameter of the fibers, pore size andwater uptake of the scaffolds were tested, respectively. TGAwas carried out to verify the percentage of HAP in the composite scaffolds fabricated with different HAP concentrations. Cell count kit-8 assay, alkaline phosphatase (ALP) assay, and osteocalcin assay were applied to observe the MC3T3-E1 cells proliferation, differentiation on the composite scaffolds. Key findings: MC3T3-E1 cellswere found to growactively on the composite scaffolds based on the results of CCK8 assay. The level ofMC3T3-E1 differentiation was evaluated through the ALP activity and osteocalcin concentration, which showed higher value with HAP containing (PLLA/PCL/HAP) than that ones without (PLLA/PCL). Significance: The results demonstrated that the biocomposite PLLA/PCL/HAP nanofibrous scaffold should be a promising candidate for proliferation, differentiation and mineralization of osteoblasts, and potentially can be used for bone tissue regeneration. (C) 2016 Elsevier Inc. All rights reserved.