The main cause of aseptic inflammation after an in vivo implantation is that Poly(L-lactide) (PLLA) and Poly(D-lactide) have a slower degradation and absorption rate, while Poly(D, L-lactide) (PDLLA) has a much faster degradation rate than PLLA because of its amorphous structure. Also, the hydrolyzate of Hydroxyapatite (HA) is alkaline, which can neutralize local tissue peracid caused by hydrolysis of Polylactic acid.,In this study, the selective laser sintering (SLS) technique was chosen to prepare bone scaffolds using nano-HA/PDLLA composite microspheres, which were prepared by the solid-in-oil-in-water (S/O/W) method. First, the SLS parameters range of bulk was determined by the result of a single-layer experiment and the optimized parameters were then obtained by the orthogonal experiment. The tensile property, hydrophobicity, biocompatibility, biological toxicity and in vitro degradation of the samples with optimized SLS parameters were characterized.,As a result, the samples showed a lower tensile strength because of the many holes in their interior, which was conducive to better cell adhesion and nutrient transport. In addition, the samples retained their inherent properties after SLS and the hydrophobicity was improved after adding nano-HA because of the OH group. Furthermore, the samples showed good biocompatibility with the large number of cells adhering to the material through pseudopods and there was no significant difference between the pure PDLLA and 10% HA/PDLLA in terms of biological toxicity. Finally, the degradation rate of the composites could be tailored by the amount of nano-HA.,This study combined the S/O/W and SLS technique and provides a theoretical future basis for the preparation of drug-loaded microsphere scaffolds through SLS using HA/PDLLA composites.

中文翻译：

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用于骨支架应用的选择性激光烧结纳米 HA/PDLLA 复合微球

体内植入后无菌性炎症的主要原因是聚（L-丙交酯）（PLLA）和聚（D-丙交酯）的降解和吸收速度较慢，而聚（D​​，L-丙交酯）（PDLLA）具有由于其非晶结构，其降解速度比 PLLA 快得多。此外，羟基磷灰石（HA）的水解产物是碱性的，可以中和聚乳酸水解引起的局部组织过酸。本研究选择选择性激光烧结（SLS）技术制备纳米HA/PDLLA骨支架采用水包油包固体（S/O/W）法制备复合微球。首先，通过单层实验的结果确定体的SLS参数范围，然后通过正交实验获得优化的参数。拉伸性能、疏水性、生物相容性、通过优化SLS参数对样品的生物毒性和体外降解进行了表征。结果，样品由于内部有许多孔洞而表现出较低的拉伸强度，这有利于更好的细胞粘附和营养运输。此外，样品在 SLS 后保留了其固有特性，并且由于 OH 基团，添加纳米 HA 后疏水性得到改善。此外，样品显示出良好的生物相容性，大量细胞通过伪足粘附在材料上，纯 PDLLA 和 10% HA/PDLLA 在生物毒性方面没有显着差异。最后，复合材料的降解率可以通过纳米 HA 的量来调整。