Abstract

The objective of this research was to synthesize and evaluate novel three dimensional scaffolds composed of poly (lactic-co-glycolic acid) (PLGA)/layered double hydroxide (LDH) composite microspheres for potential bone substitute applications. The mechanical properties of the scaffolds were found to be modulated by the sintering conditions, such as sintering temperature and sintering time, and by the PLGA/LDH ratio. After optimization, the newly developed PLGA/LDH (4:1) scaffold sintered at 90 °C for 2 h exhibited the highest mechanical properties; they were higher than those of the pure polymeric scaffold and also had a desirable pore structure for bone tissue engineering applications. The preliminary examination using L929 cells carried out and no signs of cytotoxicity were observed. The culture of G-292 cells on the optimized samples via the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium reduction assay method demonstrated increased cell proliferation compared with the pure PLGA scaffolds and the control group (a cell culture plate). Additionally, when the cells were cultured on the composite scaffolds, the osteoblasts had significantly increased alkaline phosphatase (ALP) activity relative to those on the pure PLGA scaffolds and the control group. Thus, the obtained results indicated that the PLGA/LDH microsphere-sintered scaffolds deserve attention for bone tissue engineering applications.

摘要

本研究的目的是合成和评估由聚乳酸-乙醇酸共聚物 (PLGA)/层状双氢氧化物 (LDH) 复合微球组成的新型三维支架，用于潜在的骨替代应用。发现支架的机械性能受烧结条件（如烧结温度和烧结时间）以及 PLGA/LDH 比率的调节。优化后，新开发的PLGA/LDH（4:1）支架在90℃烧结2 h后表现出最高的力学性能；它们比纯聚合物支架更高，并且还具有骨组织工程应用所需的孔结构。使用 L929 细胞进行初步检查，未观察到细胞毒性迹象。通过 MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) 四唑还原测定法在优化的样品上培养 G-292 细胞，与纯 PLGA 支架相比，细胞增殖增加和对照组（细胞培养板）。此外，当细胞在复合支架上培养时，与纯 PLGA 支架和对照组相比，成骨细胞的碱性磷酸酶 (ALP) 活性显着增加。因此，所得结果表明PLGA/LDH微球烧结支架在骨组织工程应用中值得关注。与纯 PLGA 支架和对照组（细胞培养板）相比，5-二苯基溴化四唑还原测定法显示细胞增殖增加。此外，当细胞在复合支架上培养时，与纯 PLGA 支架和对照组相比，成骨细胞的碱性磷酸酶 (ALP) 活性显着增加。因此，所得结果表明PLGA/LDH微球烧结支架在骨组织工程应用中值得关注。与纯 PLGA 支架和对照组（细胞培养板）相比，5-二苯基溴化四唑还原测定法显示细胞增殖增加。此外，当细胞在复合支架上培养时，与纯 PLGA 支架和对照组相比，成骨细胞的碱性磷酸酶 (ALP) 活性显着增加。因此，所得结果表明PLGA/LDH微球烧结支架在骨组织工程应用中值得关注。